THS4130: There is coupling between the positive and negative power supplies of THS4130？

There is a voltage divider between V_CC+ and V_CC− to set the default output common-mode voltage:

Anyway, the absolute maximum ratings forbid input voltages above V_CC+ or below V_CC−. Can this happen in your circuit, i.e., are there any input signals before V_CC+ powers up?

Hello Applo,

Power sequencing for the supply rails on fully-differential amplifiers requires some considerations:

- Absolute Maximum Ratings

- Keeping inputs floating (no signal) until Vs+ and Vs- are powered; FDAs are low-impedance inputs which will pass a voltage through the amplifier and change biasing

- If Vs+ and/or Vs- are not provided, the most negative and most positive signals become the reference/supply signals.  For example, power down or VOCM pins can end up referred to each other or inputs if no VS signals are provided

Please provide a circuit schematic or description of your setup.  If you are using our THS4130EVM, please let me know how you have the board configured.

Best,

Alec