Other Parts Discussed in Thread: TLVH431
Hello
I have an ADC driver. the supply is 5V and the Vcm (common mode voltage) should be 1.65V.
usually the common way to provide the Vcm is, using a voltage divider with two 1K resistors and one 100nF capacitor.
but when I connect the the divided voltage (3.3V/2), the output voltage is 1.68 due to the Vocm input circuit :)
another technique is, buffering the divided voltage using an op-amp to achieve better result like below :
3.3V--(using voltage divider+100nF)-->1.65V--->unity gain buffer----> connect to Vocm pin
I'm thinking of using REF2033 to provide 1.65V. when I simulate the circuit the result is outstanding! Even the SNR of the circuit is improved!
now I have a question! my circuit uses ultra low noise FDA and low distortion FDA and ICs and an 14Bit/65MSPS ADC.
is REF2033 a good option to provide the Common mode voltage?
Regards