SLOS358C September 2011 – April 2020 THS4531
The output common-model voltage is set by the voltage at the VOCM pin and the internal circuit works to maintain the output common-mode voltage as close as possible to this voltage. If left unconnected, the output common-mode is set to mid-supply by internal circuitry, which may be over-driven from an external source. Figure 75 is representative of the VOCM input. The internal VOCM circuit has about 24 MHz of -3 dB bandwidth, which is required for best performance, but it is intended to be a DC bias input pin. Bypass capacitors are recommended on this pin to reduce noise. The external current required to overdrive the internal resistor divider is given approximately by the formula:
where VOCM is the voltage applied to the VOCM pin.