Electronic inductive switching power amplifier

• US 5,781,067 A
• Filed: 04/26/1996
• Issued: 07/14/1998
• Est. Priority Date: 04/26/1996
• Status: Expired due to Fees

• Current Assignee: Tasleem Tota
• Original Assignee: Tasleem Tota
• Inventors: Tota, Tasleem
• Primary Examiner(s): Mullins, James B.
• Application Number:
  US08/638,136
• Time in Patent Office: 809 Days
• Field of Search: 330/10, 330/146, 330/207 A, 330/251
• US Class Current: 330/10
• CPC Class Codes: H03F 3/2171 with field-effect devices H03F3/2173 - H03F3/2178 take precedence

Abstract

An electronic inductive switching power amplifier designed for but not limited to amplification of electrical audio signals consists of a power conversion system, a signal control system together with a direct current power source wherein the power conversion system comprising of a pulse width modulator circuit, primary semiconductor switches and a high frequency switching transformer wherein the direct current power source is pulse width modulated through primary winding on the switching transformer by the primary semiconductor switches being controlled by the pulse width modulator. The switching transformer further comprises of a secondary winding wherein the primary to secondary winding ratio effects the required power conversion and amplification. The signal control system comprising of a multifunction preamplifier, an output driver circuit, a full wave rectifier, output semiconductor switches and a low pass electronic filter wherein the electrical audio input signal to be amplified is applied to the multifunction preamplifier thereafter producing two output signals one being an absolute value signal controlling the pulse width modulator and the second signal which is a square wave switching signal at the same frequency and phase as the input signal controlling the output driver circuit thereby producing complimentary switching signals further controlling the output semiconductor switches. The pulse width modulated output signal from the secondary winding on the switching transformer passes through the full wave rectifier and thereafter being alternately switched through the low pass filter whereby the original input waveform is reconstructed but at a greatly increased power level.

Claims

1. An Electronic Inductive Switching Power Amplifier in combination with a Direct current power source comprising,

(a) An electronic pulse width modulator circuitry in electrical communication with primary semiconductor switches in further communication with a high frequency switching transformer;

(b) A direct current primary power source electrically connected to the said pulse width modulator, further connected to primary winding on said high frequency switching transformer and to the said primary semiconductor switches through a current sensing circuit;

(c) A thermal sensing circuit in thermal communication with the said semiconductor switches and electrically connected to shutdown said pulse width modulator when thermal limits are exceeded;

(d) A multifunction preamplifier electrically connected to an input signal source and further connected to a direct current power source;

(e) The said multifunction preamplifier providing two output signals, one connected to an electrical signal isolator and the second output connected to an output driver circuit;

(f) Said signal isolator is electrically connected to input of said pulse width modulator;

(g) A secondary winding on said high frequency switching transformer is in electrical communication with a full wave rectifier in further communication with output semiconductor switches;

(h) An electronic low pass filter circuit connected to an electrical power take off point receiving signal from said output semiconductor switches and thereby connected;

(i) Said output driver circuit producing complimentary outputs electrically operates said output semiconductor switches alternately switching signal from said power take off point through said low pass filter to further operate an electrical load; and

(j) An electrical feedback signal from said power take off point connected to said multifunction preamplifier for further stability and linearity of signal amplification.

2. An electronic inductive switching power amplifier as in claim 1 wherein said multifunction preamplifier comprises an electronic circuit having a signal input point, a feedback input point and two output points, structured to amplify applied input signal, compute negative feedback and produce two input signals, one of which represents the absolute value of the said input signal suitable for operating said pulse width modulator through said signal isolator and the second signal which is a switching waveform in phase with said input waveform for electrically operating said output driver circuit.

3. An electronic inductive switching power amplifier as in claim 2 wherein said electrical signal isolator comprises an electronic device providing electrical isolation but otherwise couples between said absolute value signal and said pulse width modulator and thereby connected.

4. An electronic inductive switching power amplifier as in claim 3 wherein said pulse width modulator circuit comprises an electronic circuit operating at a minimum frequency of three times the said input signal frequency, takes in said absolute value signal and produces complimentary pulse width modulated outputs proportional to said input signal, further operating said primary semiconductor switches.

5. An electronic inductive switching power amplifier as in claim 4 wherein said thermal sensor circuit further includes a thermal sensor in thermal communication with said primary and output semiconductor switches and further provides shutdown of said pulse width modulator whenever thermal limits are exceeded.

6. An electronic inductive switching power amplifier as in claim 5 wherein said current sensor circuit further includes current sensor monitoring current through said primary semiconductor switches and further providing high current limiting and subsequent shutdown of said pulse width modulator when current limits are exceeded.

7. An electronic inductive switching power amplifier as in claim 6 wherein said primary semiconductor switches comprise semiconductor devices capable of switching high currents at high voltages and high frequencies and requiring small control signal from said pulse width modulator further taking power from said primary power source and modulating large currents through primary winding of said high frequency switching transformer.

8. An electronic inductive switching power amplifier as in claim 7 wherein said high frequency switching transformer comprises primary and secondary windings on a core material thereby capable of switching large current at high frequencies wherein said primary power source is pulse width modulated through said primary semiconductor switches through said primary winding transferring power to said secondary winding thereafter connected to said full wave rectifier.

9. An electronic inductive switching power amplifier as in claim 8 wherein said primary power source is a Direct current power source operating said pulse width modulator and associate circuitry and further includes a secondary direct current power source for operating said multifunction preamplifier, said output driver circuit and all associated circuitry.

10. An electronic inductive switching power amplifier as in claim 9 wherein said full wave rectifier comprises semiconductor devices structured to rectify high currents at high frequencies and at high voltages thereby converting alternating current output from said secondary winding of said high frequency switching transformer to a full wave pulsating direct current signal further connected to said output semiconductor switches.

11. An electronic inductive switching power amplifier as in claim 10 wherein said output semiconductor switches comprise semiconductor devices capable of switching high currents at high voltages and high frequencies requiring small electrical control signals from said output driver circuit and further connected to alternately switch said pulsating direct current signal to said power take off point through said low pass filter.

12. An electronic inductive switching power amplifier as in claim 11 wherein said low pass filter circuit comprises electronic components connected to recover low frequency signal from said pulse width modulator pulsating from said direct current power source and to further communicate recovered signal to power take off point wherein said Input signal waveform is reconstructed at a greatly increased power level for operating an electrical load.

13. An electronic inductive switching power amplifier as in claim 12 wherein said output driver circuit comprises an electronic circuit structured to take in said switching signal from said multifunction preamplifier and to further convert this signal to complementary output signals suitable for controlling said output semiconductor switches.

14. An electronic inductive switching power amplifier as in claim 13 wherein said feedback signal is taken from said power take off point and communicated to said multifunction preamplifier for providing further stability and linearity of said electronic inductive switching power amplifier.

15. An electronic inductive switching power amplifier as in claim 14 wherein said power take off point comprises electrical terminations taken at output of low pass filter with ground reference wherein said electrical load is connected.