last updated: 26 November 2002
| Class D Audio Amplifier | |
|---|---|---|
| Patent No: | 6,420,930 | |
| Date filed: | August 12, 2000 | |
| Issued:: | August 16, 2002 | |
| Inventor: | Hideto Takagishi | |
| Assignee: | Monolithic Power Systems | |
| Comments: | A self-oscillating system that uses feedback after the filter; no integrator/noise shaping other than that in the output filter and feedback network; active circuitry is just a comparator and a power stage (as with referenced Anderson). | |
| Method and Apparatus for Error Correction of Amplifier | |
| Patent No: | 6,476,674 | |
| Date filed: | January 24, 2001 | |
| Issued: | November 5, 2002 | |
| Inventor | Michael Smedegaard-Pederden; James B. Reedy | |
| Assignee: | Momentum Data Systems | |
| Comments: | Another case of putting analog and switching amp in series, this time claiming both feedback and feedforward cases. | |
| Switching Amplifier Incorporating Return-to-Zero Quaternary Power Switch | |
| Patent No: | 6,472,933 | |
| Date filed: | September 27, 1999 | |
| Issued: | October 29, 2002 | |
| Inventor: | Wei-Chan Hsu | |
| Assignee: | Waytech Investments | |
| Comments: | State transitions four four H bridge states chosen to reduce distortion; preferably driven from three-state sigma-delta | |
| Circuit for Amplifying and Outputting Audio Signals | |
| Patent No: | 6,469,575 | |
| Date filed: | March 19, 2001 | |
| Issued: | October 22, 2002 | |
| Inventor: | Masahi Oki; Kazuhiro Okamoto | |
| Assignee: | Mitsubishi | |
| Comments: | Bridge is protected from short circuit by detecting voltage across switch. | |
| Adaptive Pulse Frame Rate Frequency Control for Minimization of Electro-Magnetic Contamination in Integrated Switching Amplifier Systems | |
| Patent No: | 6,456,127 | |
| Date filed: | August 21, 2001 | |
| Issued: | September 24, 2002 | |
| Inventor: | Michael J. Tsecouras | |
| Assignee: | Texas Instruments | |
| Comments: | Adjust frequency of PWM so it won't interfere with the particular frequency the radio is tuned to. | |
| Dynamic Switching Frequency Control for a Digital Switching Amplifier | |
| Patent No: | 6,351,184 | |
| Date filed: | July 24, 2000 | |
| Issued: | February 26, 2002 | |
| Inventor: | Guoquing Miao; Cary Delano | |
| Assignee: | Tripath Technology | |
| Comments: | Dynamically adjust loop delay to a predetermined value | |
| DC Offset Calibration for a Digital Switching Amplifier | |
| Patent No: | 6,316,992 | |
| Date filed: | July 24, 2000 | |
| Issued: | November 13, 2001 | |
| Inventor: | Guoquing Miao; Cary Delano | |
| Assignee: | Tripath Technology | |
| Comments: | Measure loop and digitally store offsets in a Tripath amplifier | |
| Methods and Apparatus for Noise Shaping a Mixed Signal Power Output | |
| Patent No: | 6,297,697 | |
| Date filed: | January 11, 2001 | |
| Issued: | October 2, 2001 | |
| Inventor: | Cary L. Delano; Adya S. Tripathi | |
| Assignee: | Tripath Technology | |
| Comments: | Switching between switching and linear amp near zero crossings and at clipping where linear amp doesn't impact efficiency, | |
| Power Switching Output Stage with Dead Zone Minimization and Possibility of Parallel Synchronous Connection | |
| Patent No: | 6,288,605 | |
| Date filed: | January 18, 2000 | |
| Issued: | September 11, 2001 | |
| Inventor: | Edoardo Botti; Danilo Ranieri | |
| Assignee: | STMicroelectronics | |
| Comments: | Full bridges have event-driven cross-conduction control, allowing multiple half bridges to be directly paralleled with suitable logic. | |
| Concept and Method to Enable Filterless, Efficient Operation of Class-D Amplifiers | |
| Patent No: | 6,262,632 | |
| Date filed: | November 16, 1999 | |
| Issued: | July 17, 2001 | |
| Inventor: | Marco Corsi; Wayne Tien-Feng Chen;Roy Clifton Jones; Dan Mavencamp; Kenneth Arcudia | |
| Assignee: | Texas Instruments | |
| Comments: | Zero crossing problems in full bridge reduced by shifting one half bridge in time so ramp PWM zero crossings are shifted in time. | |
| Methods and Apparatus for Noise Shaping a Mixed Signal Power Output | |
| Patent No: | 6,229,390 | |
| Date filed: | November 2, 1999 | |
| Issued: | May 8, 2001 | |
| Inventor: | Cary L. Delano; Adya S. Tripathi | |
| Assignee: | Tripath Technology | |
| Comments: | Switching between switching and linear amp near zero crossings, clipping where linear amp doesn't impact efficiency, | |
| Modulation Scheme for Filterless Switching Amplifiers | |
| Patent No: | 6,211,728 | |
| Date filed: | November 16, 1999 | |
| Issued: | April 3, 2001 | |
| Inventor: | Wayne Tien-Feng Chen; Marco Corsi; Roy Clifton Jones; Michael David Score | |
| Assignee: | Texas Instruments | |
| Comments: | . Claims are HILARIOUS. An H bridge. An H bridge where there are multiple output states. Where the current in the load is a function of the differential voltage. Where the output voltage is a function of duty cycleŠ DUHH!!! | |
| Class D Amplifier with Pulse Width Modulation and a Very Low Power Consumption | |
| Patent No: | 6,191,650 | |
| Date filed: | June 29, 1999 | |
| Issued: | February 20, 2001 | |
| Inventor: | Lee Backram; Hans-Erik Backram; Borje Gustafsson | |
| Assignee: | G/N Netcom A/S | |
| Comments: | Simple open loop PWM full bridge | |
| Power Amplifier | |
| Patent No: | 6,188,276 | |
| Date filed: | June 18, 1999 | |
| Issued: | February 13, 2001 | |
| Inventor: | Anastasios Simopoulos | |
| Assignee: | 0 | |
| Comments: | What looks like a half bridge is in fact a low side PWM switch that acts if the output is too high, a highside PWM switch that acts if the signal is too low, each with completely separate PWM modulators, error amps, etc. | |
| Pulse-Width Modulation System | |
| Patent No: | 6,175,272 | |
| Date filed: | December 19, 1997 | |
| Issued: | January 16, 2001 | |
| Inventor: | Mark K. Takita | |
| Assignee: | Nikon | |
| Comments: | Supply rails of PWM output switched among multiple voltage rails | |
| Switching Amplifier and Method for Operating Same | |
| Patent No: | 6,172,558 | |
| Date filed: | September 2, 1999 | |
| Issued: | January 9, 2001 | |
| Inventor: | Stefan Nowak; Robert Bleisteiner | |
| Assignee: | Siemens | |
| Comments: | In connecting series full bridges, the problem of CM capacitance is addressed | |
| High Efficiency Power Amplifying Apparatus with Phase Compensation Circuit | |
| Patent No: | 6,166,596 | |
| Date filed: | March 31, 1999 | |
| Issued: | December 26, 2000 | |
| Inventor: | Katsuhiko Higashiyama; Tsuyoshi Sato | |
| Assignee: | Matsushita | |
| Comments: | Like earlier Higashiama scheme, a combination of linear amp and class D amp driving power supply. Split supply now uses just one switching amp plus two fixed DC supplies; a phase compensation network provides similar phase response in both signal paths. | |
| Power Amplifier and Method for the Drive of a Power Amplifier | |
| Patent No: | 6,160,445 | |
| Date filed: | June 2, 1999 | |
| Issued: | December 12, 2000 | |
| Inventor: | Peter Schweighofer | |
| Assignee: | Siemens | |
| Comments: | Series connected (floating) full-bridges for multi-level output | |
| Battery Polarity Insensitive Integrated Circuit Amplifier | |
| Patent No: | 6,157,252 | |
| Date filed: | September 9, 1998 | |
| Issued: | December 5, 2000 | |
| Inventor: | James Barclay Compton; Clyde Kip Brown Jr. | |
| Assignee: | TEC | |
| Comments: | Primarily for hearing aids, CMOS circuit includes Class D amp and circuit to connect to battery of in either polarity. | |
| Device for Amplifying Digital Signals | |
| Patent No: | 6,140,875 | |
| Date filed: | August 5, 1998 | |
| Issued: | October 31, 2000 | |
| Inventor: | Johannes A.T.M. Van Den Homberg; Kathleen J.P. Philips | |
| Assignee: | Philips | |
| Comments: | Continuous time feedback allows input of DSD stream into second order hysteretic loop. The use of feedforward of the digital stream supposedly reduces effects of clock jitter. | |
| Power Amplifier with Soft Switching and Multilevel Switching Cells | |
| Patent No: | 6,140,873 | |
| Date filed: | July 28, 1999 | |
| Issued: | October 31, 2000 | |
| Inventor: | Wilhelmus D.H. Van Groningen | |
| Assignee: | Philips | |
| Comments: | A multilevel inverter for high voltage high power MRI applications | |
| Class D Amplifiers Including Transition Zone Modulation | |
| Patent No: | 6,127,885 | |
| Date filed: | August 31, 1998 | |
| Issued: | October 3, 2000 | |
| Inventor: | Thomas Phillip Michael Colangelo | |
| Assignee: | Cello Ltd | |
| Comments: | At low outputs, slew rate of switching drops to low value, minimizing RFI and improving distortionŠ | |
| Amplifiers | |
| Patent No: | 6,124,757 | |
| Date filed: | October 6, 1997 | |
| Issued: | September 26, 2000 | |
| Inventor: | Christopher Newey | |
| Assignee: | Harman Intl. | |
| Comments: | Digital to PWM; an FM modulation of the PWM adjusts for supply variation | |
| Start-up Circuit For Self Oscillating Class D Modulator | |
| Patent No: | 6,118,336 | |
| Date filed: | October 30, 1998 | |
| Issued: | September 12, 2000 | |
| Inventor: | Stuart W. Pullen; Donald R. Preslar | |
| Assignee: | Intersil | |
| Comments: | Adding ENABLE and MUTE to a hysteretic converter. | |
| Digital Input Switching Audio Power Amplifier | |
| Patent No: | 6,107,876 | |
| Date filed: | April 13, 1999 | |
| Issued: | August 22, 2000 | |
| Inventor: | Thomas Joseph Obrien | |
| Assignee: | Ravisent Technologies | |
| Comments: | Seria-Parallel-Oversample-Interpolate-LINEARIZER(??)-Noise Shaping-PWM all digital chain. | |
| Variable Frequency Class D Modulator with Built In Soft Clipping and Frequency Limiting | |
| Patent No: | 6,107,875 | |
| Date filed: | October 15, 1998 | |
| Issued: | August 22, 2000 | |
| Inventor: | Stewart W. Pullen; Patrick A. Begley; Donald R. Preslar | |
| Assignee: | Intersil | |
| Comments: | Hysteretic loop has input limiting to prevent clipping, also prevents loop from modulating down to audio range at high output levels. | |
| Audio Amplifier with Tracking Power Supply Utilizing Inductive Power Converter | |
| Patent No: | 6,104,248 | |
| Date filed: | March 31, 1999 | |
| Issued: | August 15, 2000 | |
| Inventor: | Robert W. Carver | |
| Assignee: | ||
| Comments: | Class G with dynamic rails from switcher, independent on each rail | |
| Method and Device for Improved Class BD Amplification Having Single Terminal Alternating-Rail Dual-Sampling Technology | |
| Patent No: | 6,097,249 | |
| Date filed: | September 2, 1998 | |
| Issued: | August 1, 2000 | |
| Inventor: | James C. Strickland; Carlos A. Castrejon | |
| Assignee: | Rockford | |
| Comments: | Two bridges half bridges in series; output half bridge switches GND to +V or GND to -V depending on first half bridge | |
| High Efficiency Power Amplifying Apparatus | |
| Patent No: | 6,091,292 | |
| Date filed: | March 31, 1999 | |
| Issued: | July 18, 2000 | |
| Inventor: | Katsuhiko Higashiyama; Tsuyoshi Sato | |
| Assignee: | Matsushita | |
| Comments: | Two switching Amps, offset in DC, supply low voltage rails for linear output amp. (Not exactly class GŠ) | |
| PWM Controller with One Cycle Response | |
| Patent No: | 6,084,450 | |
| Date filed: | February 13, 1998 | |
| Issued: | July 4, 2000 | |
| Inventor: | K. Mark Smith; Zheren Lai; Keyue M. Smedley | |
| Assignee: | UC Regents | |
| Comments: | Self-oscillating scheme that eliminates frequency modulation | |
| High Efficiency Class DB Power Amplifier | |
| Patent No: | 6,078,214 | |
| Date filed: | March 22, 1999 | |
| Issued: | June 20, 2000 | |
| Inventor: | Zhengwei Zhang | |
| Assignee: | Texas Instruments | |
| Comments: | H Bridge drives into caps rather than inductors, silly use of discrete time processing. (some body saw a description of using switchcaps as resistors, gives inherent ramp action for PWMŠ) | |
| System for Enabling a Full-Bridge Switch-Mode Amplifier to Recover All Reactive Energy | |
| Patent No: | 6,072,362 | |
| Date filed: | July 10, 1998 | |
| Issued: | June 6, 2000 | |
| Inventor: | Daniel J. Lincoln | |
| Assignee: | Ameritherm | |
| Comments: | Variations on std. H bridge to reduce HF losses | |
| High Power High Performance Pulse Width Modulation Amplifier | |
| Patent No: | 6,064,259 | |
| Date filed: | July 24, 1998 | |
| Issued: | May 16, 2000 | |
| Inventor: | Mark K. Takita | |
| Assignee: | Nikon | |
| Comments: | Well written but not clear what is new - a delay element is added into loop; a notch at the switching frequency in the LC output filter. | |
| Signal Processing Apparatus with Selective Power Amplification | |
| Patent No: | 6,028,944 | |
| Date filed: | March 4, 1997 | |
| Issued: | February 22, 2000 | |
| Inventor: | Mitchell A. Markow; Rabah S. Hamdi | |
| Assignee: | Compaq | |
| Comments: | In laptop computer, low power switching amp is used under battery power, higher power linear amp under mains power. | |
| Audio Amplifier System Using a Class D Amplifier | |
| Patent No: | 6,028,943 | |
| Date filed: | March 27, 1999 | |
| Issued: | February 22, 2000 | |
| Inventor: | Koichiro Nagato | |
| Assignee: | Matsushita | |
| Comments: | Two channels have switch freq. > 20kHz apart | |
| Power Switched Amplifier | |
| Patent No: | 6,028,476 | |
| Date filed: | July 21, 1998 | |
| Issued: | February 22, 2000 | |
| Inventor: | Peter Schweighofer | |
| Assignee: | Siemens | |
| Comments: | Variable elements in output filter, for NMR | |
| Class D Amplifier Input Structure | |
| Patent No: | 6,016,075 | |
| Date filed: | June 4, 1997 | |
| Issued: | January 18, 2000 | |
| Inventor: | David J. Hamo | |
| Assignee: | Lord Corp. | |
| Comments: | Use a differential amp for feedback from full bridge | |
| Class D Amplifier with Reduced Clock Requirement and Related Methods | |
| Patent No: | 6,014,055 | |
| Date filed: | February 6, 1998 | |
| Issued: | January 11, 2000 | |
| Inventor: | David B. Chester | |
| Assignee: | Intersil | |
| Comments: | Digital input amp; oversampled, noise shaped, then digital to PWM via separate PWMs for MSB and LSBs | |
| Current Mode Switching for Tristate Amplifiers in Magnetic Bearing Control System | |
| Patent No: | 6,005,316 | |
| Date filed: | December 10, 1998 | |
| Issued: | December 21, 1999 | |
| Inventor: | Timothy A. Harris | |
| Assignee: | Revolve Magnetic Bearings | |
| Comments: | Two bit PWM signal controls Bridge switching pattern | |
| Method and Apparatus for Processing an Analog Signal | |
| Patent No: | 5,994,954 | |
| Date filed: | March 4, 1997 | |
| Issued: | November 30, 1999 | |
| Inventor: | David Smith; Ross Nimmo | |
| Assignee: | Texas Instruments | |
| Comments: | WOW In 1997, using a ramp and a comparator, TI patents the pulse width modulatorŠ | |
| Method and Apparatus for Improved Power Transfer Efficiency of an Amplifier System | |
| Patent No: | 5,990,751 | |
| Date filed: | October 16, 1997 | |
| Issued: | November 23, 1999 | |
| Inventor: | Mark K. Takita | |
| Assignee: | Nikon | |
| Comments: | Class G with dynamic rails from switcher, independent on each rail | |
| Method and Apparatus for High Efficiency Power Amplification | |
| Patent No: | 5,990,735 | |
| Date filed: | April 1, 1998 | |
| Issued: | November 23, 1999 | |
| Inventor: | Bernard Eugene Sigmon; Ronald Gene Myers | |
| Assignee: | Motorola | |
| Comments: | Multiple converters on single chip combined (prior to transmitter) | |
| Audio Direct from Power Supply | |
| Patent No: | 5,986,498 | |
| Date filed: | April 14, 1998 | |
| Issued: | November 16, 1999 | |
| Inventor: | Manuel D. Rodriguez | |
| Assignee: | Harman Intl. | |
| Comments: | Traffo coupled; followed by polarity switch | |
| Multiple Channel Class D Audio Amplifier | |
| Patent No: | 5,982,231 | |
| Date filed: | July 23, 1997 | |
| Issued: | November 9, 1999 | |
| Inventor: | Mehmet K. Nalbant | |
| Assignee: | Linfinity | |
| Comments: | Two full bridges on a chip? | |
| Method and Apparatus for Performance Improvement by Qualifying Pulses in an Oversampled Noise-Shaping Signal Processor | |
| Patent No: | 5,974,089 | |
| Date filed: | July 22, 1997 | |
| Issued: | October 26, 1999 | |
| Inventor: | Adya S. Tripathi; Cary L. Delano | |
| Assignee: | Tripath | |
| Comments: | Qualifying logic follows Delta-Sigma | |
| Class D amplifier with Switching Control | |
| Patent No: | 5,963,086 | |
| Date filed: | August 8, 1997 | |
| Issued: | October 5, 1999 | |
| Inventor: | David S. Hall | |
| Assignee: | Velodyne | |
| Comments: | Two extra switches, another L, to control recirculating energy | |
| Class-D Amplifier No Low Pass Filter Feedback with Zero Phase Delay | |
| Patent No: | 5,949,282 | |
| Date filed: | February 25, 1998 | |
| Issued: | September 7, 1999 | |
| Inventor: | Huey Nguyen; Hideto Takagishi | |
| Assignee: | National Semiconductor | |
| Comments: | HILARIOUS! | |
| Pulse Width Modulator with Automatic Gain Control Over-Voltage Modulator and Limiter | |
| Patent No: | 5,917,369 | |
| Date filed: | February 25, 1998 | |
| Issued: | June 29, 1999 | |
| Inventor: | Huey Nguyen | |
| Assignee: | National Semiconductor | |
| Comments: | Processing of overloads, and for some reason trying to prevent full modulation by imposing artificial max D. | |
| Method and Apparatus for compensating for delays in Modulator Loops | |
| Patent No: | 5,909,153 | |
| Date filed: | February 5, 1998 | |
| Issued: | June 1, 1999 | |
| Inventor: | Cary L. Delano; Adya S. Tripathi | |
| Assignee: | Tripath | |
| Comments: | Oh boy! The introduction of zeros in the loop to improve stability. (Avoiding of course any such basic explanation for the techniques usedŠ) | |
| High Efficiency Power Amplifier using Combined Linear and Switching Techniques with Novel Feedback System | |
| Patent No: | 5,905,407 | |
| Date filed: | July 30, 1997 | |
| Issued: | May 18, 1999 | |
| Inventor: | Pallab Midya | |
| Assignee: | Motorola | |
| Comments: | Switching amp is used as current dumper in combined Linear/Switching scheme. | |
| Delta-Sigma Pulse Width Modulator Control Circuit | |
| Patent No: | 5,901,176 | |
| Date filed: | October 16, 1997 | |
| Issued: | May 4, 1999 | |
| Inventor: | Richard S. Lewison | |
| Assignee: | Hewlett-Packard | |
| Comments: | Converting Delta-Sigma to PWM | |
| High Power Efficiency Audio Power Amplifier with Digital Audio and Volume Inputs | |
| Patent No: | 5,898,340 | |
| Date filed: | October 20, 1996 | |
| Issued: | April 27, 1999 | |
| Inventor: | Manjirnath A. Chatterjee; Gregory R. Simon | |
| Assignee: | 0 | |
| Comments: | Volume control sets supply rails for switching amp | |
| Class D Hearing Aid Amplifier with Feedback | |
| Patent No: | 5,815,581 | |
| Date filed: | October 19, 1995 | |
| Issued: | September 29, 1998 | |
| Inventor: | Olle Andersson | |
| Assignee: | Mitel | |
| Comments: | Interesting IC design of PWM based amplifier; feedback directly from switches | |
| Silent Start Class D Amplifier | |
| Patent No: | 5,805,020 | |
| Date filed: | June 27, 1996 | |
| Issued: | September 8, 1998 | |
| Inventor: | George Edward Danz; Larry A. King; John K. Fogg | |
| Assignee: | Harris | |
| Comments: | A switch(or variable element) kills the gain of the loop integrator at start-up in a conventional PWM loop | |
| Single Output Dual Supply Class D Amplifier | |
| Patent No: | 5,798,672 | |
| Date filed: | July 9, 1996 | |
| Issued: | August 25, 1998 | |
| Inventor: | Marco Masini; Claudio Tavazzani; Stephania Boioccchi | |
| Assignee: | SGS-Thomson | |
| Comments: | Extension of multivibrator-type modulator to have supply feedforward; IC realization for split-supply sensing. | |
| Single Pole Negative Feedback for Class D Amplifier | |
| Patent No: | 5,796,302 | |
| Date filed: | July 9, 1996 | |
| Issued: | August 18, 1998 | |
| Inventor: | Marco Masini; Stephania Boioccchi; Edoardo Botti | |
| Assignee: | SGS-Thomson | |
| Comments: | Multivibrator based PWM with feedback from the switching output | |
| Method and Apparatus for Oversampled, Noise Shaping, Mixed-Signal Processing | |
| Patent No: | 5,777,512 | |
| Date filed: | June 19, 1996 | |
| Issued: | July 7, 1998 | |
| Inventor: | Adya S. Tripathi; Cary L. Delano | |
| Assignee: | Tripath | |
| Comments: | Cont. time Delta Sigma w/state & output FB | |
| Switching Amplifier Closed Loop Dual Comparator Modulation Technique | |
| Patent No: | 5,767,740 | |
| Date filed: | September 27, 1996 | |
| Issued: | June 16, 1998 | |
| Inventor: | John K. Fogg | |
| Assignee: | Harris | |
| Comments: | Two comparators to get Full bridge signals, Differential feedback. | |
| Method of Driving a Class D Audio Power Amplifier Using Non-Overlapping Edge Drive Signals | |
| Patent No: | 5,729,175 | |
| Date filed: | April 26, 1996 | |
| Issued: | March 17, 1998 | |
| Inventor: | Enrique Ferrer | |
| Assignee: | Motorola | |
| Comments: | Wow! Moto patents using deadtime to prevent shoot-through! | |
| Class D Amplifier and Method | |
| Patent No: | 5,672,998 | |
| Date filed: | August 9, 1995 | |
| Issued: | September 30, 1997 | |
| Inventor: | Harold Allen Wittlinger | |
| Assignee: | Harris | |
| Comments: | Rather than using feedback to analog input, feedback is taken to a point after analog to single bit (ramp PWM in this case) | |
| Digital Signal Processing for Linearization of Small Input Signals to a Tri-state Power Switch | |
| Patent No: | 5,617,058 | |
| Date filed: | November 13, 1995 | |
| Issued: | April 1, 1997 | |
| Inventor: | Andrew A. Adrian; Michael S Danielson; David B. Meyers; Leo Spiegel | |
| Assignee: | Apogee | |
| Comments: | Digital in; DSP compensates for low level distortion | |
| Output Transformerless Amplifier Impedance Matching Apparatus | |
| Patent No: | 5,612,646 | |
| Date filed: | March 30, 1995 | |
| Issued: | March 18, 1997 | |
| Inventor: | David W. Berning | |
| Assignee: | ||
| Comments: | Push pull triode amp uses h.f. DC:DC techniques to couple high voltage output to loudspeaker load. (I guess a bunch of ferrite cores plus power devices are improvement over a large iron core transformerŠ) | |
| Switching Amplifier with Impedance Transformation Output Stage | |
| Patent No: | 5,610,553 | |
| Date filed: | March 2, 1994 | |
| Issued: | March 11, 1997 | |
| Inventor: | Larry Kirn | |
| Assignee: | 0 | |
| Comments: | Unusual output has too many switches, but can drive load beyond nominal supply rails | |
| Pulse Width Modulated Amplifier | |
| Patent No: | 5,594,386 | |
| Date filed: | April 21, 1995 | |
| Issued: | January 14, 1997 | |
| Inventor: | Timothy A. Dhuyvetter | |
| Assignee: | Sipex | |
| Comments: | Hysteretic loop closed with state feedback alone. | |
| Stereo Audio Codec | |
| Patent No: | 5,589,830 | |
| Date filed: | November 2, 1994 | |
| Issued: | December 31, 1996 | |
| Inventor: | Alfredo R. Linz; Carlin D. Cabler; Glen W. Brown; Martin P. Soques | |
| Assignee: | AMD | |
| Comments: | Solid presentation of digital audio processing in well written patent | |
| Digital Pulse Width Modulation Power Amplifier with Noise and Ripple Shaping | |
| Patent No: | 5,559,467 | |
| Date filed: | January 27, 1995 | |
| Inventor: | September 24, 1996 | |
| Inventor: | Keyue M. Smedley | |
| Assignee: | Regents of UC | |
| Comments: | Digital in, noise shaped, converted to PWM. No output feedback, but a feedforward of supply rails is implemented. | |
| Reducing Switching Losses in a Phase-Modulated Switch-Mode Amplifier | |
| Patent No: | 5,541,827 | |
| Date filed: | May 17, 1995 | |
| Issued: | July 30, 1996 | |
| Inventor: | Lars P. Allfather | |
| Assignee: | Doble | |
| Comments: | Phase mod the half bridges, use overlapping clocks on secondary | |
| Stabilization of Closed Loop Power Controllers | |
| Patent No: | 5,521,549 | |
| Date filed: | July 19, 1994 | |
| Issued: | May 28, 1996 | |
| Inventor: | Robert G. Nelson | |
| Assignee: | ||
| Comments: | Applies high order loop (similar to Modgil) to ramp type PWM loops | |
| Composite Bridge Amplifier with Output overload and Thermal Protection | |
| Patent No: | 5,510,753 | |
| Date filed: | November 22, 1994 | |
| Issued: | April 23, 1996 | |
| Inventor: | John B. French | |
| Assignee: | Blade Technologies | |
| Comments: | Single ended power stage followed by a non-switching Full Bridge that merely sets the output polarity. Also includes over-current, overtemp protection | |
| Pulse Width Modulation Amplifier | |
| Patent No: | 5,508,663 | |
| Date filed: | September 20, 1994 | |
| Inventor: | April 16, 1996 | |
| Inventor: | Fumiyasy Konno | |
| Assignee: | Matsushita | |
| Comments: | To eliminate the High DC offset caused by DC loop with high DC gain operational amplifiers (!?!), the DC gain of the loop amp is reduced to unity and inputs and feedback are AC coupled. (i.e open loop at DC to improve offset???) | |
| Power Amplifier Circuit for Audio Signal and Audio Device Using the Same | |
| Patent No: | 5,483,197 | |
| Date filed: | September 26, 1994 | |
| Inventor: | January 9, 1996 | |
| Inventor: | Kei Nishioka; Masanori Fujisawa; Katsumi Kusaba | |
| Assignee: | Rohm | |
| Comments: | Full bridge linear amp has its supplies provided dynamically by a switching amp | |
| Very Low Power Loss Amplifier for Analog Signals Utilizing Constant Frequency Zero Voltage Switching Multi-resonant Converter | |
| Patent No: | 5,479,337 | |
| Date filed: | November 30, 1993 | |
| Issued: | December 26, 1995 | |
| Inventor: | William C. Voigt | |
| Assignee: | Kaiser Aerospace | |
| Comments: | Multi-resonant loading of bridge to get low switching losses | |
| Switching Regulator and Amplifier System | |
| Patent No: | 5,442,317 | |
| Date filed: | March 10, 1995 | |
| Issued: | August 15, 1995 | |
| Inventor: | Robert E. Stengel; David E. Muri; Enrique Ferrer | |
| Assignee: | Motorola | |
| Comments: | Input signal controls a DC:DC that supplies a full bridge. If DC:DC has continuous output, the bridge supplies only direction signal. If DC:DC has discrete outputs, then Bridge uses PWM | |
| Distortion Compensation for a Pulsewidth-Modulated Circuit | |
| Patent No: | 5,438,694 | |
| Date filed: | August 9, 1993 | |
| Issued: | August 1, 1995 | |
| Inventor: | David L. Muri; Robert E. Stengel | |
| Assignee: | Motorola | |
| Comments: | Digital storage of distortion characteristics to predistort PWM. (Look-up table /microcontroller approach). | |
| Means and Method of Enhancing Signal Resolution and Dynamic Range Extension in a Pulse Width Modulated Amplifier. | |
| Patent No: | 5,422,597 | |
| Date filed: | 4/31/94 | |
| Issued: | June 6, 1995 | |
| Inventor: | Robert E. Stengel; David E. Muri; Enrique Ferrer | |
| Assignee: | Motorola | |
| Comments: | Output stages with large devices or tiny devices are selectively used as output requires to maximize efficiency | |
| Class'D' Audio Speaker Amplifier with State Variable Feedback | |
| Patent No: | 5,410,592 | |
| Date filed: | June 4, 1993 | |
| Issued: | April 25, 1995 | |
| Inventor: | Randall M. Wagner; Yogi L. Mistry | |
| Assignee: | Harris | |
| Comments: | State Variable voltage and current feedback | |
| Pulse Width Modulation Speaker Amplifier | |
| Patent No: | 5,398,003 | |
| Date filed: | March 30, 1994 | |
| Issued: | March 14, 1998 | |
| Inventor: | Lawrence F. Heyl; Steven E. Austin | |
| Assignee: | Apple Computer | |
| Comments: | Open loop amplifier with volume control, PCM input, Offset elimination (on input signal), dynamic range control, etc. | |
| Output Limiter for Class D BiCMOS Hearing Aid Output Amplifier | |
| Patent No: | 5,389,829 | |
| Date filed: | September 30, 1992 | |
| Issued: | February 14, 1995 | |
| Inventor: | Ciro Milazzo | |
| Assignee: | Exar | |
| Comments: | limiter is digital pulse qualification following modulator that enforces a minimum/maximum duty cycle. | |
| Pulsewidth-Modulated Amplifier Having Analog Mode | |
| Patent No: | 5,382,915 | |
| Date filed: | July 6, 1993 | |
| Issued: | January 17, 1995 | |
| Inventor: | David L. Muri; Robert E. Stengel | |
| Assignee: | Motorola | |
| Comments: | Dual mode amplifier switches to analog mode for low signal levels | |
| Closed Loop Power Controller | |
| Patent No: | 5,352,986 | |
| Date filed: | January 22, 1993 | |
| Issued: | October 4, 1994 | |
| Inventor: | Onkar S. Modgil; Robert G. Nelson; Margaret S. Reif | |
| Assignee: | Digital Fidelity | |
| Comments: | Higer order loop in triangle PWM (high loop gain in-band) | |
| Amplification Circuit | |
| Patent No: | 5,347,230 | |
| Date filed: | June 17, 1992 | |
| Issued: | September 13, 1994 | |
| Inventor: | Masao Noro | |
| Assignee: | Yamaha | |
| Comments: | Class G with self-tracking PWM rails | |
| Pulse Width Modulation Amplifier | |
| Patent No: | 5,262,733 | |
| Date filed: | March 9, 1992 | |
| Issued: | November 16, 1993 | |
| Inventor: | Yasafumi Nakajima; Toshihiko Oohashi | |
| Assignee: | Matsushita | |
| Comments: | Simple ramp PWM but ramp is proportional to supply for gain feedforward | |
| Four Quadrant Current Mode Switching Amplifier | |
| Patent No: | 5,225,789 | |
| Date filed: | April 17, 1992 | |
| Issued: | July 6, 1993 | |
| Inventor: | Steven L. Caine, Mahlon D. Kimbrough | |
| Assignee: | Nortel | |
| Comments: | current traffo reports current info; odd power architecture | |
| Switching Amplifier | |
| Patent No: | 5,218,315 | |
| Date filed: | January 6, 1992 | |
| Issued: | June 8, 1993 | |
| Inventor: | Wheeler M. Turner | |
| Assignee: | Infinity | |
| Comments: | hysteretic modulator with additional pole plus a delay element in the loop | |
| Pulse Duration Amplifier System Having Distortion Reduction | |
| Patent No: | 5,216,376 | |
| Date filed: | June 10, 1992 | |
| Issued: | June 1, 1993 | |
| Inventor: | Hilmer J. Swanson | |
| Assignee: | Harris | |
| Comments: | Multiple amplifiers paralleled; feedforward correction for supply variations | |
| Class D loop | |
| Patent No: | 5,160,896 | |
| Date filed: | February 18, 1992 | |
| Issued: | November 3, 1992 | |
| Inventor: | David P. McCorkle | |
| Assignee: | Harman Intl. | |
| Comments: | Hyst. Loop w/ supply and input dependent hysteresis, CM/DM filtering, muting, sleep functionality | |
| Dual Feedback Control for a High-Efficiency Class-D Power Amplifier Circuit | |
| Patent No: | 5,118,997 | |
| Date filed: | August 16, 1991 | |
| Issued: | June 2, 1992 | |
| Inventor: | Sayed-Amr A. El Hamamsy | |
| Assignee: | GE | |
| Comments: | For ballast operation; two control loops adjust resonant network to optimize efficiency | |
| Class D MOSFET Amplifier and Voltage Supply Balance Circuit Therefor | |
| Patent No: | 5,117,198 | |
| Date filed: | April 8, 1991 | |
| Issued: | May 26, 1992 | |
| Inventor: | Kenneth Morrenz | |
| Assignee: | ||
| Comments: | Avoiding body diode conduction by splitting output inductor; similar scheme can be used to control supply pumping | |
| Power Amplifier for Feeding an Inductor with Switched Transistors | |
| Patent No: | 5,113,145 | |
| Date filed: | February 27, 1991 | |
| Issued: | May 12, 1992 | |
| Inventor: | Karl-Heniz Ideler; Stefan Nowak; Gunter Petzold | |
| Assignee: | Siemens | |
| Comments: | Interesting high power scheme; changes to bridge to aid parallel ling, mechanical/thermal design | |
| Minimum Pulse Width Switching Power Amplifier | |
| Patent No: | 5,077,540 | |
| Date filed: | June 14, 1990 | |
| Issued: | December 31, 1991 | |
| Inventor: | F. Joseph Keith; Eric H. Maslin | |
| Assignee: | U. of Virginia | |
| Comments: | Minimum pulse width digital qualification in a loop with loop closed around output current | |
| Switching Amplifier | |
| Patent No: | 5,077,539 | |
| Date filed: | December 26, 1990 | |
| Issued: | December 31, 1991 | |
| Inventor: | John R. Howett | |
| Assignee: | Apogee | |
| Comments: | 3 state, optional 4th state is analog amp, selected based on _signal_level_ | |
| Composite Bridge Amplifier with Output overload and Thermal Protection | |
| Patent No: | 5,075,634 | |
| Date filed: | November 23, 1990 | |
| Issued: | December 24, 1991 | |
| Inventor: | John B. French | |
| Assignee: | Blade Technologies | |
| Comments: | Half Bridge provides PWM, direction into load is from baseband fullbridge steering. | |
| Switching Amplifier | |
| Patent No: | 5,014,016 | |
| Date filed: | April 13, 1989 | |
| Issued: | May 7, 1991 | |
| Inventor: | James R. Anderson | |
| Assignee: | Beltone | |
| Comments: | Basic PWM full bridge. Two half bridges modulated independently; three state switching results. | |
| Audio Amplifier with Phase Modulated Pulse Width Modulation | |
| Patent No: | 4,992,751 | |
| Date filed: | October 17, 1989 | |
| Issued: | February 12, 1991 | |
| Inventor: | Brian E. Attwod; Larry E. Hand; Fred C. Santillano | |
| Assignee: | Peavey | |
| Comments: | Excellent teaching; Shows development of PM bridge using diode/FET bidirectional switches. System shown is open loop. | |
| Ultra Efficient Switching Power Amplifier | |
| Patent No: | 4,980,649 | |
| Date filed: | July 8, 1989 | |
| Issued: | December 25, 1990 | |
| Inventor: | Zdzislaw Gulezynski | |
| Assignee: | ||
| Comments: | Transformer plus two bidirectional switches allow four quadrant output; bad class B and odd switching | |
| Pulse Width Modulation Amplifier Circuit | |
| Patent No: | 4,968,948 | |
| Date filed: | July 14, 1989 | |
| Issued: | November 6, 1990 | |
| Inventor: | Aiko Tokumo; Masayuki Kato; Takeshi Sato; Tatsuzo Hasegawa | |
| Assignee: | Pioneer | |
| Comments: | Two sides of bridge driven from in-phase clocks; common mode choke with low (audio freq) cutoff can be used. | |
| Pulse Width Modulation Amplifier Circuit | |
| Patent No: | 4,952,884 | |
| Date filed: | August 3, 1989 | |
| Issued: | August 28, 1990 | |
| Inventor: | Aiko Tokumo; Masayuki Kato; Takeshi Sato; Tatsuzo Hasegawa | |
| Assignee: | Pioneer | |
| Comments: | Radiation is reduced by wobble (FM the carrier with random signal) | |
| Pulse Width Modulation Amplifier Circuit | |
| Patent No: | 4,949,048 | |
| Date filed: | November 3, 1989 | |
| Issued: | August 14, 1990 | |
| Inventor: | Aiko Tokumo; Masayuki Kato; Takeshi Sato; Tatsuzo Hasegawa | |
| Assignee: | Pioneer | |
| Comments: | Two sides of bridge driven from separate modulators from quadrature clocked PWMs | |
| Digital Audio Amplifier | |
| Patent No: | 4,724,396 | |
| Date filed: | August 21, 1984 | |
| Issued: | January 13, 1986 | |
| Inventor: | Wilson E. Taylor; Larry R. Hand | |
| Assignee: | Peavey | |
| Comments: | Improved version of Peavey's clipping detection via missing pulses; limiting scheme based on reducing gain near clipping. | |
| Digitally Driven Switching Power Amp System | |
| Patent No: | 4,683,439 | |
| Date filed: | January 9, 1986 | |
| Issued: | July 28, 1987 | |
| Inventor: | Jay W. Atherton; Raymond A. Castor; Leonard F Christie; Robert C. Engerman | |
| Assignee: | Honeywell | |
| Comments: | Open loop digital amp; shows conversion to PWM, for digitally synthesized signals | |
| Apparatus and Method for Muting an Output Signal in a Switching Amplifier | |
| Patent No: | 4,673,889 | |
| Date filed: | December 16, 1985 | |
| Issued: | June 16, 1987 | |
| Inventor: | Carlo Cini; Claudin Diazzi; Pietro Erratico | |
| Assignee: | SGS Microelettronica | |
| Comments: | Muting and turn-on pop reduction by gating and clamping points in the loop | |
| Power Control System | |
| Patent No: | 4,673,888 | |
| Date filed: | September 2, 1986 | |
| Issued: | June 16, 1987 | |
| Inventor: | Rudolph H. Engelman; Thad Early | |
| Assignee: | Electro-Voice | |
| Comments: | Multi-level switching to drive loudspeaker | |
| Digital Driver for Fixed Power Amplifier | |
| Patent No: | 4,673,887 | |
| Date filed: | January 3, 1986 | |
| Issued: | June 16, 1987 | |
| Inventor: | Jay W. Atherton | |
| Assignee: | Honeywell | |
| Comments: | analog->digital->phase modulated->full bridge | |
| Digital Audio Amplifier Having High Power Output Level and Low Distortion | |
| Patent No: | 4,600,891 | |
| Date filed: | August 21, 1984 | |
| Issued: | July 15, 1986 | |
| Inventor: | Wilson E. Taylor; Larry R. Hand | |
| Assignee: | Peavey | |
| Comments: | NICE teaching, detects overload by missing pulses, Compensates for body diode errors, sophisticated output filter, nested feedback | |
| Switching Amplifier System | |
| Patent No: | 4,573,018 | |
| Date filed: | April 19, 1984 | |
| Issued: | February 25, 1986 | |
| Inventor: | Fred Mirow | |
| Assignee: | ||
| Comments: | Traffo coupled power stage followed by polarity switch; basically DC:DC with split variable outputs and a post-filter switch to tie load to the proper polarity. A really bad class-B PWM approach | |
| Flyback Modulated Power Amplifier | |
| Patent No: | 4,571,551 | |
| Date filed: | February 28, 1984 | |
| Issued: | February 18, 1986 | |
| Inventor: | Wesley H. Trager | |
| Assignee: | Washington Innovative Technology | |
| Comments: | Flyback control is odd: Don't switch while body diode conducts; forces output current to drop to zero every cycle (why?) | |
| Power Amplifier | |
| Patent No: | 4,560,946 | |
| Date filed: | March 21, 1984 | |
| Issued: | December 24, 1985 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippon Gakki | |
| Comments: | High voltage, high efficiency amp drives one end of load, a low voltage high quality amp drives the other. | |
| Switching Amplifier for Digital Power Amplification | |
| Patent No: | 4,560,944 | |
| Date filed: | April 18, 1984 | |
| Issued: | December 24, 1985 | |
| Inventor: | Andreas Furrer | |
| Assignee: | Brown Boveri | |
| Comments: | Another multi-level switching scheme, with interesting interleaving. | |
| Switching Amplifier with MOSFET Driver Circuit | |
| Patent No: | 4,554,512 | |
| Date filed: | November 19, 1985 | |
| Issued: | November 19, 1985 | |
| Inventor: | Michael E. Aiello | |
| Assignee: | Aerotech | |
| Comments: | PWM full bridge uses RF carrier through tiny gate drive transformers for level shift | |
| Pulse Width Modulation Amplifier Circuit | |
| Patent No: | 4,531,096 | |
| Date filed: | September 28, 1983 | |
| Issued: | July 23, 1985 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippon Gakki | |
| Comments: | Adds BBM, second order loop amplifier, feedback from switches | |
| Pulse Width Modulation Circuit with Carrier Signal Frequency Control | |
| Patent No: | 4,524,335 | |
| Date filed: | March 10, 1983 | |
| Issued: | June 18, 1985 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippon Gakki | |
| Comments: | PWM frequency is made a function of signal; Triangle PWM emulates hysteretic loop? Justification is actually funny. | |
| High Efficiency Feedforward-Error-Correction Amplifier | |
| Patent No: | 4,523,152 | |
| Date filed: | March 30, 1983 | |
| Issued: | June 11, 1985 | |
| Inventor: | Peter Garde | |
| Assignee: | Unisearch Ltd. | |
| Comments: | Analog amp corrects errors in switching output; in final version analog amp doubles as loop error amp (as with Walker) | |
| Switching Amplifier | |
| Patent No: | 4,510,457 | |
| Date filed: | January 10, 1983 | |
| Issued: | April 9, 1985 | |
| Inventor: | Andreas Furrer; Johann Milavec | |
| Assignee: | Brown Boveri | |
| Comments: | Multiple amps summed on secondaries | |
| Protection Circuit for Switching Amplifier | |
| Patent No: | 4,509,101 | |
| Date filed: | August 15, 1983 | |
| Issued: | April 2, 1985 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippon Gakki | |
| Comments: | Current limiting scheme senses current from the rails | |
| Pulse Width Modulation Circuit with Carrier Signal Frequency Control | |
| Patent No: | 4,504,793 | |
| Date filed: | January 4, 1983 | |
| Issued: | March 12, 1985 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippon Gakki | |
| Comments: | A feedback loop is placed around a ramp PWM, improving linearity (imagine that!) | |
| Method and Apparatus for Amplifying an Analog low Frequency Signal by a Switching Amplifier | |
| Patent No: | 4,488,121 | |
| Date filed: | January 28, 1982 | |
| Issued: | November 11, 1984 | |
| Inventor: | Andreas Furrer; Vaclau Mertl; Johann Milavec; Herbert Stemmler | |
| Assignee: | Brown Boveri | |
| Comments: | Multi-level switched amp. One of the worst-taught patents I've ever seen! | |
| Pulse Width Modulated Power Amp | |
| Patent No: | 4,484,145 | |
| Date filed: | December 8, 1981 | |
| Issued: | November 20, 1984 | |
| Inventor: | Tord L. Haulin | |
| Assignee: | Ericsson | |
| Comments: | Using PWM on push-pull primary, fixed 50% or zero on independent bilateral secondary switches | |
| Phase Modulated Switchmode Power Amplifier and Waveform Generator | |
| Patent No: | 4,479,175 | |
| Date filed: | August 13, 1982 | |
| Issued: | October 23, 1984 | |
| Inventor: | Robert A. Gille; Norman G. Planer; Zoltan Zansky | |
| Assignee: | Honeywell | |
| Comments: | Four switch Phase modulation scheme, shown as push-pull. Four quadrant output at fixed frequency and fixed (50%) duty cycle. Henceforth referenced in relation to co-inventor Zansky, who promoted this scheme. | |
| Power Amplifier | |
| Patent No: | 4,476,436 | |
| Date filed: | August 25, 1981 | |
| Issued: | October 9, 1984 | |
| Inventor: | Akio Koizumi; Hiroshi Yamagishi | |
| Assignee: | Sony | |
| Comments: | Amplitude modulating the base drive for bipolar PWM | |
| Hybrid Pulse Width Modulated Audio Amplifier | |
| Patent No: | 4,471,314 | |
| Date filed: | June 15, 1981 | |
| Issued: | September 11, 1984 | |
| Inventor: | Charles R. Lindberg | |
| Assignee: | ||
| Comments: | Put any switching amp on a hybrid substrate (how novel!) | |
| Pulse Width Modulated Signal Amplifier | |
| Patent No: | 4,458,208 | |
| Date filed: | April 9, 1982 | |
| Issued: | July 3, 1984 | |
| Inventor: | Miki Abe | |
| Assignee: | Sony | |
| Comments: | PWM loop is held in low gain open loop during startup | |
| Dual Mode Amplifier | |
| Patent No: | 4,446,440 | |
| Date filed: | January 26, 1982 | |
| Issued: | May 1, 1984 | |
| Inventor: | R. Frank Bell | |
| Assignee: | Hewlett-Packard | |
| Comments: | PWM at high levels, switches to linear for small signals | |
| Class D Pulse Width Modulated Amplifier | |
| Patent No: | 4,439,738 | |
| Date filed: | October 12, 1981 | |
| Issued: | March 27, 1984 | |
| Inventor: | Jay W. Atherton | |
| Assignee: | Honeywell | |
| Comments: | Transformer coupled, a switch shorts the transformer during deadtime | |
| Power Amplifier | |
| Patent No: | 4,430,625 | |
| Date filed: | June 23, 1981 | |
| Issued: | February 7, 1984 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippan Gakki | |
| Comments: | Linear amp with Class G output has additional dynamic class D amp to drive nominal supplies in the class G to improve efficiency. (Only would go true class G if PWM amp failed to keep up with the signal swing). | |
| Pulse Width Modulation Amplifier | |
| Patent No: | 4,415,863 | |
| Date filed: | March 24, 1981 | |
| Issued: | November 15, 1983 | |
| Inventor: | Akio Tokumo | |
| Assignee: | Pioneer | |
| Comments: | Ramp PWM uses feedback from switching output | |
| Pulse Width Modulated Amplifier | |
| Patent No: | 4,415,862 | |
| Date filed: | March 24, 1981 | |
| Issued: | November 15, 1983 | |
| Inventor: | Yoshiro Konugi | |
| Assignee: | Pioneer | |
| Comments: | Two stereo channels have common clock, but produce outputs that are 90 degrees out, to minimize switching interaction. | |
| Amplifier Employing Digital Modulator Circuit | |
| Patent No: | 4,403,197 | |
| Date filed: | October 26, 1981 | |
| Issued: | September 6, 1983 | |
| Inventor: | Hilmer I. Swanson | |
| Assignee: | Harris | |
| Comments: | Binary weighted signals summed into transmitter, PWM between Digital values for more resolution | |
| Pulse Width Modulated Power Amplifier with Differential Connecting Line Voltage Drop Comparator | |
| Patent No: | 4,403,196 | |
| Date filed: | April 22, 1981 | |
| Inventor: | September 6, 1983 | |
| Inventor: | Paul E. Grandmont | |
| Assignee: | US Air Force | |
| Comments: | Compensates for cabling drop: If one has access to load, why not just close the loop there??? | |
| Audio Power Amp with Class-D Push-Pull Output Stage | |
| Patent No: | 4,390,849 | |
| Date filed: | April 28, 1981 | |
| Issued: | July 28, 1983 | |
| Inventor: | Leslie Miskin | |
| Assignee: | ITT | |
| Comments: | Digital input takes high order bits to PWM, lower bits drive A/D that modifies pulse amplitude. Walker is referenced, as are Vanderkooy & Lipshitz, who extended Walkers current dumper to a switching amp. | |
| Power Amplifier Connection | |
| Patent No: | 4,390,846 | |
| Date filed: | January 21, 1981 | |
| Issued: | June 28, 1983 | |
| Inventor: | Gunnar Cragfors; Jurgen Bosson | |
| Assignee: | ASEA Actiebolag | |
| Comments: | Linear Amp corrects output via feedback; Switching amp driven from error signal in linear amp. | |
| Digitally Driven Combination Coils for electrodynamics Acoustic Transducer | |
| Patent No: | 4,360,707 | |
| Date filed: | November 24, 1980 | |
| Issued: | November 23, 1982 | |
| Inventor: | Joel R. Joseph; William F. Bleeke | |
| Assignee: | CTS | |
| Comments: | Two single ended anti-phase drives for opposing coils on loudspeaker. | |
| Pulse Width Modulated Signal Amplifier | |
| Patent No: | 4,347,481 | |
| Date filed: | May 19, 1980 | |
| Issued: | March 31, 1982 | |
| Inventor: | Tadao Yoshida | |
| Assignee: | Sony | |
| Comments: | Separate supplies for (bipolar) switches and freewheeling diodes to minimize the difference in output voltage as a function of current direction | |
| Multi-Channel Audio Power Amplifier | |
| Patent No: | 4,346,349 | |
| Date filed: | May 7, 1980 | |
| Issued: | August 24, 1982 | |
| Inventor: | Kenji Yokoyama | |
| Assignee: | Nippon Gakki | |
| Comments: | Summing a switching (LF) and linear (HF) amp in single loop. Neglects to reference PJ Walker! | |
| Pulse-Width Modulator Circuit | |
| Patent No: | 4,337,438 | |
| Date filed: | February 13, 1980 | |
| Issued: | June 29, 1982 | |
| Inventor: | Water Guggenbuhl; Mathis Halder | |
| Assignee: | LGZ Landis | |
| Comments: | A notch filter in the output low-pass includes a means to force the oscillator to stay tuned to the notch. | |
| PWM Signal Power Amplifier | |
| Patent No: | 4,249,136 | |
| Date filed: | May 22, 1979 | |
| Issued: | February 3, 1981 | |
| Inventor: | Tadao Suzuki; Tadeo Yoshida | |
| Assignee: | Sony | |
| Comments: | Feedback from output closes around integrator, comparator, output stage. (First order loop) | |
| Linearized Three state Switching Amplifier | |
| Patent No: | 4,240,036 | |
| Date filed: | April 13, 1979 | |
| Issued: | December 15, 1980 | |
| Inventor: | Thomas P. Kohler | |
| Assignee: | GE | |
| Comments: | This is class AB approach to improve prior art, well-known three-state switching approach | |
| Class D Amplifier System | |
| Patent No: | 4,178,556 | |
| Date filed: | April 19, 1978 | |
| Issued: | December 11, 1979 | |
| Inventor: | Brian E. Attwood | |
| Assignee: | 0 | |
| Comments: | Nested feedback loops around triangle type PWM | |
| Pulse Width Modulated Signal Amplifier with Protective Means | |
| Patent No: | 4,167,710 | |
| Date filed: | October 28, 1977 | |
| Issued: | September 11, 1979 | |
| Inventor: | Tadao Suzuki; Tadeo Yoshida | |
| Assignee: | Sony | |
| Comments: | Supply pumping on LF signals is detected and the amp is shut down if supply exceeds a max value. (First Sony patent showing MOS output stage) | |
| Polyphase PDM Amplifier | |
| Patent No: | 4,164,714 | |
| Date filed: | September 26, 1977 | |
| Issued: | August 14, 1979 | |
| Inventor: | Hilmer J. Swanson | |
| Assignee: | Harris | |
| Comments: | Multiple PWMs from n-phase clocks summed (into transmitter) | |
| Amplifier Systems | |
| Patent No: | 4,162,455 | |
| Date filed: | January 4, 1978 | |
| Issued: | July 24, 1979 | |
| Inventor: | David R. Birt | |
| Assignee: | Communications Patents Ltd. | |
| Comments: | Two power stages with anti-phase ripple feed load. | |
| High Efficiency Amplifier | |
| Patent No: | 4,153,882 | |
| Date filed: | March 24, 1978 | |
| Issued: | May 8, 1979 | |
| Inventor: | Charles B. Fisher; Sidney T. Fisher | |
| Assignee: | 0 | |
| Comments: | Multi-level based on switching multiple transformer taps on both primary and secondary for Nyquist rate conversion | |
| Negative Feedback Amplifier of PWM-Type | |
| Patent No: | 4,144,502 | |
| Date filed: | October 26, 1977 | |
| Issued: | March 13, 1979 | |
| Inventor: | Yuji Ikeda | |
| Assignee: | Sansui | |
| Comments: | Basic scheme with feedback from the load. Adding ESR to the cap introduces a zero which helps stability. | |
| Pulse Width Modulated Amplifier | |
| Patent No: | 4,059,807 | |
| Date filed: | October 29, 1975 | |
| Issued: | November 22, 1977 | |
| Inventor: | Osamu Hamade | |
| Assignee: | Sony | |
| Comments: | Absolute classic PWM amp; single integrator in loop with Ramp PWM modulator, feedback from after output filter. | |
| Pulse Width Modulated Signal Amplifier | |
| Patent No: | 4,021,745 | |
| Date filed: | December 16, 1975 | |
| Issued: | March 3, 1977 | |
| Inventor: | Tadao Suzuki; Tadeo Yoshida | |
| Assignee: | Sony | |
| Comments: | Single integrator loop with feedback from switches; loop integrator also integrates square clock to create [ramp + integrated error] signal | |
| Switching Amplifier System | |
| Patent No: | 4,016,501 | |
| Date filed: | December 29, 1975 | |
| Issued: | April 5, 1977 | |
| Inventor: | Leon Jasinski; Francis Robert Steed | |
| Assignee: | Motorola | |
| Comments: | Half bridge with unipolar PWM into directional switching Bridge around load. | |
| Pulse Width Modulated Signal Amplifier | |
| Patent No: | 4,015,213 | |
| Date filed: | February 23, 1976 | |
| Issued: | March 29, 1977 | |
| Inventor: | Osamu Hamade | |
| Assignee: | Sony | |
| Comments: | Loop similar to hysteretic with feedback from switch output, but on-time is set by linear ramp; off-time by the loop integrator. | |
| Pulse Width Modulated Signal Amplifier | |
| Patent No: | 4,004,246 | |
| Date filed: | March 3, 1975 | |
| Issued: | January 18, 1977 | |
| Inventor: | Osamu Hamade | |
| Assignee: | ||
| Comments: | Full Bridge PWM with differential feedback from load | |
| Pulse Width Modulated Signal Amplifier | |
| Patent No: | 3,999,143 | |
| Date filed: | December 16, 1975 | |
| Issued: | December 21, 1976 | |
| Inventor: | Tadao Yoshida; Tadao Suzuki | |
| Assignee: | Sony | |
| Comments: | Bipolars lack body diodes. A scheme for connecting diodes to a rail lower than nominal VDD; eliminating the step change going from sourcing to sinking. | |
| Distortion Free Amplifier | |
| Patent No: | 3,970,953 | |
| Date filed: | January 10, 1975 | |
| Issued: | July 20, 1976 | |
| Inventor: | P.J> Walker; Michael Peter Albinson | |
| Assignee: | Acoustic Mfg Co | |
| Comments: | Quad 405 Current Dumping amp; Using small high quality feedforward amp to correct for current dumper (Class B in original patent) Both in Walker's published work and in other inventors' this was extended to using a PWM plus linear amp. | |
| High Efficiency Switching Power Amplifier | |
| Patent No: | 3,931,581 | |
| Date filed: | September 30, 1974 | |
| Issued: | January 6, 1976 | |
| Inventor: | Louis J.Kush Jr.; Claus P. Janota, Richard D. Koontz, Leon H. Sibul | |
| Assignee: | Navy | |
| Comments: | Bipolar H bridge w/ base drive traffos; BBM, for LF sonar | |
| Amplification System | |
| Patent No: | 3,648,186 | |
| Date filed: | March 24, 1970 | |
| Issued: | March 7, 1972 | |
| Inventor: | Leonard R. Kahn | |
| Assignee: | Kayn Research | |
| Comments: | PWM modulates class C amp, which gives power gain. RF output is detected back to baseband. Two opposing schemes give (class B) bipolar output. (OK, I admit - this makes the list as my token vacuum tube switching amp!) | |
| Power Amplifier | |
| Patent No: | 3,636,380 | |
| Date filed: | September 4, 1970 | |
| Issued: | January 18, 1972 | |
| Inventor: | Vernon A. Anderson | |
| Assignee: | US Navy | |
| Comments: | Self oscillating loop where active stages are comparator and power output. Feedback from switches fed back through unspecified feedback network. | |
| High Efficiency Power Amplifier | |
| Patent No: | 3,585,517 | |
| Date filed: | May 1, 1968 | |
| Issued: | June 15, 1971 | |
| Inventor: | Roger B. Herbert | |
| Assignee: | Westinghouse | |
| Comments: | Class BD scheme with direct coupled bipolar full-bridge, three state switching, Ramp based PWM with feedback | |
| Class D Linear Audio Amplifier | |
| Patent No: | 3,579,132 | |
| Date filed: | November 14, 1969 | |
| Issued: | May 18, 1971 | |
| Inventor: | James A. Ross | |
| Assignee: | LTV Ling Altec | |
| Comments: | A means to drive transformer coupled drive signals of Full, Half bridges zero to 100% duty cycle; basic open loop ramp PWM architecture | |
| Simplified Pulse Width Modulated Amplifier | |
| Patent No: | 3,509,479 | |
| Date filed: | November 29, 1966 | |
| Issued: | April 28, 1970 | |
| Inventor: | George C. Gucker; Paul H. Daitch | |
| Assignee: | Sperry | |
| Comments: | Feedback PWM (square wave injected into Gm-C integrator cap); Output stage is 3-state half bridge (Zero state is low Z) | |
| High Efficiency RF Power Amplification with Modulation Signal Controlled ON-OFF Switch Varied Amplifier DC Potential | |
| Patent No: | 3,413,570 | |
| Date filed: | February 23, 1966 | |
| Issued: | November 26, 1968 | |
| Inventor: | Warren B. Breune; Tom L. Dennis Jr.; Edgar O. Schoenike | |
| Assignee: | Collins Radio | |
| Comments: | Switching Amp provides signal dependent rails for AM RF Amplifier | |
| Solid State Switching Type Linear Amplifier | |
| Patent No: | 3,400,334 | |
| Date filed: | November 12, 1964 | |
| Issued: | September 3, 1968 | |
| Inventor: | James A. Ross; Tadeusz W. Maciejowski; Thomas R. Parkhill | |
| Assignee: | Ling-Temco-Vought | |
| Comments: | Ramp type open loop PWM with transformer coupled bipolar half bridge | |
| Two-State Power Amplifier with Transitional Feedback | |
| Patent No: | 3,336,538 | |
| Date filed: | August 13, 1964 | |
| Issued: | August 15, 1967 | |
| Inventor: | Norman H. Crowhurst | |
| Assignee: | 0 | |
| Comments: | THREE state amplifier actually. Power stage is transformer coupled push-pull. At zero crossing, minimum pulse widths drive in either direction and are amplitude modulated (very advanced, unique.) Zero state is high Z. Feedback system with ramp modulator. | |
| Modulator-Demodulator Amplifier | |
| Patent No: | 3,253,228 | |
| Date filed: | April 12, 1962 | |
| Issued: | May 24, 1966 | |
| Inventor: | Joseph Montner | |
| Assignee: | Aerojet | |
| Comments: | Open loop amp for inverters uses 3 state output; Power stage is transformer coupled bipolar push-pull, PWM modulator is ether ramp type or mag amp PWM (!!) | |
| Control Apparatus Including a Switch and Both Positive and Negative Feedback | |
| Patent No: | 3,225,216 | |
| Date filed: | September 6, 1962 | |
| Issued: | December 21, 1965 | |
| Inventor: | John H. Grabowski | |
| Assignee: | Honeywell | |
| Comments: | Pos. feedback around switch gives more solid switching, but hysteresis. A global NFB can reduce the hysteresis. Additional NFB (delayed) creates a negative hysteresis in the form of a PWM. Interesting description of self-oscillating PWM modulator. | |
| Controller Circuitry with pulse Width Modulator | |
| Patent No: | 3,090,929 | |
| Date filed: | December 18, 1959 | |
| Issued: | May 21, 1963 | |
| Inventor: | Francis T. Thompson | |
| Assignee: | Westinghouse | |
| Comments: | Minor loop feedback (I.e. local state feedback) linearizes modulator | |
| Electric Signal Transmission System | |
| Patent No: | 2,491,969 | |
| Date filed: | October 14, 1946 | |
| Issued: | December 20, 1949 | |
| Inventor: | Paul Francois Marie Gloess | |
| Assignee: | Sadir Carpentier | |
| Comments: | Actually for distributing digital PWM signals; but is a feedback PWM scheme for improved linearity | |