Analog to pulse width modulation (PWM) circuit

1. A system comprising:

an error detection and correction module ( 104 ) configured to receive an analog input signal ( 102 ) and a feedback signal ( 112 ) and generate a correction signal ( 118 ); and

an analog to pulse width modulation (PWM) module ( 106 ) configured to receive the analog input signal ( 102 ) and the correction signal ( 118 ) and generate a PWM output signal ( 116 );

wherein the generated PWM output signal ( 116 ) is fed back to the error detection and correction module ( 104 ) as said feedback signal ( 112 ).

2. The system of claim 1 , wherein the error detection and correction module ( 104 ) comprises a PWM to analog module ( 108 ).

3. The system of claim 2 , wherein the PWM to analog module ( 108 ) is configured to receive the feedback signal ( 112 ) and the analog input signal ( 102 ) and generate an analog signal.

4. The system of claim 3 , wherein the error detection and correction module ( 104 ) further comprises an error comparator module ( 110 ).

5. The system of claim 4 , wherein the error comparator module ( 110 ) is configured to receive and compare the analog signal from the PWM to analog module ( 108 ) with the analog input signal ( 102 ) to generate an error correction signal ( 208 ) proportional to the feedback signal ( 112 ).

6. The system of claim 1 , wherein the analog to PWM module ( 106 ) comprises a low-pass filter ( 210 ).

7. The system of claim 6 , wherein the low-pass filter ( 210 ) receives and integrates the correction signal ( 118 ) and generates a triangle wave signal ( 212 ).

8. The system of claim 7 , wherein the analog to PWM module ( 106 ) further comprises an output comparator ( 214 ).

9. The system of claim 8 , wherein the output comparator ( 214 ) receives and compares the triangle wave signal ( 212 ) to the analog input signal ( 102 ) and generates the PWM output signal ( 116 ), wherein the PWM output signal ( 116 ) comprises a duty cycle proportional to the analog input signal ( 102 ).

10. The system of claim 2 , wherein the PWM to analog module ( 108 ) further comprises a digital-to-analog converter (DAC) ( 202 ).

11. The system of claim 10 , wherein the DAC ( 202 ) receives the feedback signal ( 112 ) and a reference signal ( 114 ) and converts feedback signal ( 112 ) to an analog output signal ( 203 ).

12. The system of claim 11 , wherein the PWM to analog module ( 108 ) further comprises a low-pass (LP) filter ( 204 ).

13. The system of claim 12 , wherein the LP filter ( 204 ) receives the analog output signal ( 203 ) and generates an output signal ( 205 ), wherein the output signal ( 205 ) from the LP filter ( 204 ) is proportionate to a duty cycle of the analog input signal ( 102 ).

14. The system of claim 13 , wherein the error detection and correction module ( 104 ) further comprises an error comparator module ( 110 ), and wherein the error comparator module ( 110 ) further comprises an error comparator ( 206 ).

15. The system of claim 14 , wherein the error comparator ( 206 ) receives and compares the output signal ( 205 ) from the LP filter ( 204 ) to the analog input signal ( 102 ) and generates an error correction signal ( 208 ), wherein the error correction signal ( 208 ) has a duty cycle that is proportional to that of the feedback signal ( 112 ).

16. A method comprising:

receiving an analog input signal ( 102 ) at an error detection and correction module ( 104 ) and an analog to pulse width modulation (PWM) module ( 106 );

receiving a feedback signal ( 112 ) at the error detection and correction module ( 104 );

generating a correction signal ( 118 ) at the error detection and correction module ( 104 ) based on the received analog input signal ( 102 ) and the received feedback signal ( 112 );

receiving the correction signal ( 118 ) at the analog to PWM module ( 106 );

generating a PWM output signal ( 116 ) at the analog to PWM module ( 106 ) based on the received correction signal ( 118 ), wherein the generated PWM output signal ( 116 ) is fed back to the error detection and correction module ( 104 ) as said feedback signal ( 112 ).

17. The method of claim 16 , wherein generating the PWM output signal ( 116 ) further comprises:

comparing the analog input signal ( 102 ) to a triangle wave signal ( 212 ).

18. The method of claim 16 , further comprising:

returning the feedback signal ( 112 ) back into the error detection and correction module ( 104 ), whereby signal artifacts are removed from the feedback signal ( 112 ) using a digital-to-analog converter (DAC) ( 202 ).

19. The method of claim 18 , wherein generating the correction signal ( 118 ) further comprises:

extracting an average of the DAC output signal ( 203 ) using a low-pass filter ( 204 ); and

generating an error signal ( 208 ) by comparing an output of the low-pass filter ( 204 ) to the analog input signal ( 102 ).

20. The method of claim 19 , wherein generating the PWM output signal ( 116 ) further comprises:

integrating the error signal ( 208 ) with a low-pass filter ( 210 ) to generate a triangle wave signal ( 212 ); and

comparing the analog input signal ( 102 ) with the triangle wave ( 212 ) output from the low-pass filter ( 210 ), using a comparator ( 214 ) to convert the analog input signal ( 102 ) to a precision PWM output signal ( 116 ).