Active DC output control and method for DC/DC converter
View Patent ↗A control loop system is provided that employs an active DC output control circuit that more accurately calibrates the desire voltage at a load, e.g. 3.3 volts, by adjusting a trim pin on a DC/DC converter. In a first embodiment, an active DC output control circuit calibrates a DC/DC converter that is connected to a single load. In a second embodiment, an active DC output control circuit calibrates multiple DC/DC converters that are connected to multiple loads.
1. A system for a single load, comprising:
an active DC output control circuit;
a DC/DC converter having a trim pin and coupled to the active DC output control circuit; and
a load, coupled to the DC output control circuit and the DC/DC converter, the DC/DC converter generating a DC/DC output voltage level to the load;
wherein the DC output control circuit comprises an input voltage sensing and signal conditioning circuit;
wherein the input voltage sensing and signal conditioning circuit comprises a digital analog converter for scaling the DC/DC output voltage level based on a digital scaling factor without the use of analog to digital converter and a digital processor;
wherein the active DC output control circuit drives the trim pin for calibrating the DC/DC output voltage level.
2. A system for a single load, comprising:
an active DC output control circuit;
a DC/DC converter having a trim pin and coupled to the active DC output control circuit; and
a load, coupled to the DC output control circuit and the DC/DC converter, the DC/DC converter generating a DC/DC output voltage level to the load;
wherein the DC output control circuit comprises an input voltage sensing and signal conditioning circuit;
wherein the input voltage sensing and signal conditioning circuit comprises a digital analog converter;
wherein the active DC output control circuit drives the trim pin for calibrating the DC/DC output voltage level;
wherein the active DC output control circuit comprises a NV (non-volatile) memory;
wherein the NV memory stores only data for maintaining the desired output voltage settings.
3. The system of claim 2 , wherein the active DC output control circuit comprises:
a control logic, connected to the NV memory;
an input voltage sensing and signal conditioning circuit for receiving a V+ signal; and
a comparator, coupled to the input voltage sensing and signal conditioning circuit, for comparing a reference voltage and the V+ signal and generating a comparator output signal.
4. The system of claim 3 , wherein input voltage sensing and signal conditioning circuit comprises the digital analog converter, an amplifier, and a filter.
5. The system of claim 4 , further comprising a ground, coupled to the active DC output control circuit and the load.
6. A system for multiple loads, comprising:
an active DC output control circuit having a first of N control pins;
a first of N DC/DC converters, connected to the active DC output control circuit; and
a first of N loads, coupled to the DC output control circuit and the first of N DC/DC converters, the first of N DC/DC converters generating a DC/DC output voltage levels to the first of N loads;
wherein the DC output control circuit comprises an input voltage sensing and signal conditioning circuit;
wherein the input voltage sensing and signal conditioning circuit comprises a digital analog converter for scaling the DC/DC output voltage level based on a digital scaling factor without the use of analog to digital converter and a digital processor;
wherein the active DC output control circuit drives the first of N control pins for calibrating the DC/DC output voltage level for each load generated from the first of N DC/DC converters.
7. The system of claim 6 , further comprising:
a second of N DC/DC converters, coupled to the active DC output control circuit; and
a second of N loads, coupled to the DC output control circuit and the second of N DC/DC converters, the second of N DC/DC converters generating a DC/DC output voltage level to the second of N loads;
wherein the active DC output control circuit drives a second trim pin for calibrating the DC/DC output voltage level generated from the second of N DC/DC converters.
8. The system of claim 7 , further comprising a ground, coupled commonly to the first of N loads and the second of N loads.
9. The system of claim 6 , wherein the active DC output control circuit comprises a NV (non-volatile) memory to maintain the desired output voltage settings.
10. The system of claim 9 , wherein the active DC output control circuit comprises:
a control logic, coupled to the NV memory;
an input voltage sensing and signal conditioning circuit for receiving a V+ signal and a V− signal; and
a comparator, coupled to the input voltage sensing and signal conditioning circuit for comparing a reference voltage and the V+ signal, and generating a comparator output signal.
11. The system of claim 6 , wherein the input voltage sensing and signal conditioning circuit comprises the digital analog converter, an amplifier, and a filter.
12. A method for calibrating a single load, comprising:
measuring an output voltage level from a DC/DC converter having a trim pin;
scaling the output voltage level using a digital analog converter based on a digital scaling factor without the use of analog to digital converter and a digital processor;
comparing the scaled output voltage level with a reference voltage;
adjusting the input signal of the DC/DC converter trim pin for calibrating the output voltage level with respect to the reference voltage.
13. The method of claim 12 , further comprising, between the measuring step and the comparing step, adjusting the reference voltage using a level shifter.
14. The method of claim 12 , further comprising, between the measuring step and the comparing step, filtering the output voltage level.
15. The method of claim 12 , wherein in the comparing step, if the output voltage level is greater than the reference voltage and the DC/DC converter has a positive polarity, adjusting the first trim pin slightly downward to decrease the output voltage level.
16. The method of claim 12 , wherein in the comparing step, if the output voltage level is less than the reference voltage and the DC/DC converter has a positive polarity, adjusting the first trim pin slightly upward to increase the output voltage level.
17. The method of claim 12 , wherein in the comparing step, if the output voltage level is greater than the reference voltage and the DC/DC converter has a negative polarity, adjusting the first trim pin slightly upward to decrease the output voltage level.
18. The method of claim 12 , wherein in the comparing step, if the output voltage level is less than the reference voltage and the DC/DC converter has a negative polarity, adjusting the first trim pin slightly downward to increase the output voltage level.
19. The method of claim 12 , wherein the input signal of the DC/DC converter trim pin comprises a voltage signal.
20. The method of claim 12 , wherein the input signal of the DC/DC converter trim pin comprises an electrical current signal.
21. A method for calibrating multiple loads, comprising:
measuring a first output voltage level from a first of N DC/DC converters having a first of N trim pins;
scaling the first output voltage level using a digital analog converter based on a digital scaling factor without the use of analog to digital converter and a digital processor;
comparing the scaled first output voltage level with a reference voltage;
adjusting the input signal of the first of N trim pins on the first of N DC/DC converters to calibrate the first output voltage level with respect to the reference voltage;
repeating the process for each of N DC/DC converters.
22. The method of claim 21 , further comprising:
measuring a second output voltage level from a second of N DC/DC converters;
comparing the second output voltage level with a second reference voltage;
adjusting a first trim pin to calibrate the first output voltage level with respect to the second reference voltage.
23. The method of claim 21 , further comprising, between the measuring step and the comparing step, scaling the each first output voltage level.
24. The method of claim 21 , further comprising, between the measuring step and the comparing step, filtering the first output voltage level.
25. The method of claim 21 , wherein in the comparing step, if the first output voltage level is greater than the first reference voltage and the DC/DC converter has a positive polarity, adjusting the first trim pin slightly downward to decrease the first output voltage level.
26. The method of claim 21 , wherein in the comparing step, if the first output voltage level is less than the first reference voltage and the DC/DC converter has a positive polarity, adjusting the first trim pin slightly upward to increase the first output voltage level.
27. The method of claim 21 , wherein in the comparing step, if the output voltage level is greater than the reference voltage and the DC/DC converter has a negative polarity, adjusting the first trim pin slightly upward to decrease the output voltage level.
28. The method of claim 21 , wherein in the comparing step, if the first output voltage level is less than the first reference voltage and the DC/DC converter has a negative polarity, adjusting the first trim pin slightly downward to increase the first output voltage level.
29. The method of claim 21 , wherein in the comparing step, if the second output voltage level is greater than the second reference voltage and the first of N DC/DC converters has a positive polarity, adjusting the second trim pin slightly downward to decrease the second output voltage level.
30. The method of claim 21 , wherein in the comparing step, if the second output voltage level is less than the second reference voltage and the second of N DC/DC converters has a positive polarity, adjusting the second trim pin slightly upward to increase the second output voltage level.
31. The method of claim 21 , wherein in the comparing step, if the second output voltage level is greater than the second reference voltage and the second of N DC/DC converters has a negative polarity, adjusting the second trim pin slightly upward to decrease the second output voltage level.
32. The method of claim 21 , wherein in the comparing step, if the second output voltage level is less than the second reference voltage and the second of N DC/DC converters has a negative polarity, adjusting the second trim pin slightly downward to increase the second output voltage level.