Dynamic common mode control
An apparatus such as an electronic circuit includes an input operable to receive an input signal; a dynamic common mode adjustor operable to: i) derive a differential signal from the received input signal, and ii) control an offset of the differential signal as a function of the received input signal to produce an offset differential signal; and an output operable to output the offset differential signal. In one arrangement, the offset differential signal outputted from the output includes a first signal and a second signal; a difference between the second signal and the first signal proportionally varies with respect to the received input signal.
1. An apparatus comprising:
an input operable to receive an input signal;
a signal generator operable to derive an output signal from the received input signal, an offset of the output signal varied as a function of a magnitude of the input signal; and
an output operable to output the offset output signal.
2. The apparatus as in claim 1 , wherein the signal generator is further operative to vary a magnitude of the output signal depending on the magnitude of the received input signal.
3. The apparatus as in claim 1 , wherein an increase in the magnitude of the received input signal results in an increased magnitude of the offset.
4. The apparatus as in claim 1 , wherein a decrease in the magnitude of the received input signal results in a decreased magnitude of the offset.
5. The apparatus as in claim 1 , wherein the signal generator is operable to set a magnitude of the offset to zero for magnitudes of the received input signal greater than a threshold value.
6. The apparatus as in claim 1 , wherein a magnitude of the output signal varies linearly with respect to the received input signal.
7. The apparatus as in claim 1 , wherein the signal generator is further operable to generate the offset as a first value during operating conditions in which the magnitude of the received input signal is within a first voltage range.
8. The apparatus as in claim 7 , wherein the signal generator is further operable to generate the offset as a second value during operating conditions in which the magnitude of the received input signal is within a second voltage range.
9. The apparatus as in claim 7 , wherein the first range includes a value of zero.
10. The apparatus as in claim 1 , wherein the signal generator is operative to proportionally vary a magnitude of the offset with respect to a magnitude of the received input signal.
11. The apparatus as in claim 1 , wherein the offset is set to a fixed value during operating conditions in which the received input signal falls within a first range; and
wherein the offset varies during operating conditions in which the received input signal falls within a second range.
12. A method comprising:
receiving an input signal;
deriving an output signal from the received input signal;
varying an offset of the output signal as a function of the received input signal; and
outputting the offset output signal.
13. The method as in claim 12 further comprising:
varying a magnitude of the output signal depending on a magnitude of the received input signal.
14. The method as in claim 12 , wherein an increase in a magnitude of the received input signal results in an increased magnitude of the offset.
15. The method as in claim 12 , wherein a decrease in a magnitude of the received input signal results in a decreased magnitude of the offset.
16. The method as in claim 12 further comprising:
setting a magnitude of the offset to a fixed value for magnitudes of the received input signal greater than a threshold value.
17. The method as in claim 12 further comprising:
varying a magnitude of the output signal with respect to a magnitude of the received input signal.
18. The method as in claim 12 further comprising:
generating the offset as a first value during operating conditions in which the magnitude of the received input signal is within a first voltage range.
19. The method as in claim 18 further comprising:
generating the offset as a second value during operating conditions in which the magnitude of the received input signal is within a second voltage range.
20. The method as in claim 18 , wherein the first range includes a value of zero.
21. The method as in claim 12 , wherein a magnitude of the offset is proportional with respect to a magnitude of the received input signal.
22. The method as in claim 12 , wherein the offset is set to a fixed value during operating conditions in which the received input signal falls within a first range; and
wherein the offset varies during operating conditions in which the received input signal falls within a second range.
23. Computer-readable storage hardware having instructions stored thereon, the instructions, when carried out by computer processor hardware, cause the computer processor hardware to:
receive an input signal;
derive an output signal from the received input signal;
vary an offset of the output signal as a function of the received input signal; and
output the offset output signal.
24. The apparatus as in claim 1 , wherein the offset output signal is a summation of the offset and the output signal.
25. The apparatus as in claim 24 , wherein a magnitude of the offset is greater than zero.
26. The apparatus as in claim 25 , wherein a magnitude of the output signal is greater than zero.
27. The apparatus as in claim 24 , wherein both a magnitude of the offset and a magnitude of the output signal vary depending on a magnitude of the input signal.
28. The apparatus as in claim 27 , wherein the signal generator amplifies the input signal to produce the output signal.
29. The apparatus as in claim 1 , wherein the signal generator is operative to: i) receive offset adjustment settings, and ii) generate a magnitude of the offset applied to the output signal to be a non-zero value based on the offset adjustment settings.
30. The apparatus as in claim 1 , wherein the signal generator is operable to set the offset to a first offset value in response to a first condition in which the magnitude of the received input signal is a first value; and
wherein the signal generator is operable to set the offset to a second offset value in response to a second condition in which the magnitude of the received input signal is a second value.
31. The apparatus as in claim 1 , wherein the signal generator is operative to vary a magnitude of the offset in accordance with a piece-wise linear adjustment function.
32. The apparatus as in claim 1 , wherein the input signal is a digital signal; and
wherein the offset output signal is an analog signal.
33. The apparatus as in claim 1 , wherein the signal generator uses map information to map a magnitude of the input signal to the offset.