SBOS932C January 2020 – March 2021 THP210
The THP210 has two functional modes: normal operation and power-down. The power-down state is enabled when the voltage on the power-down pin is lowered to less than the power-down threshold. In the power-down state, the quiescent current is significantly reduced, and the output voltage is high-impedance. This high impedance can lead to the input voltages (VIN+ and VIN–) separating.
Internal ESD protection diodes remain present across the input pins in both operating and power-down mode. Large input signals during disable can forward-biasing the ESD protection diodes, thus producing a load current in the supply, even in power-down. See Section 9.1.5 for guidance on power-down operation.
The VOCM control pin sets the output average voltage. If left open, VOCM defaults to an internal midsupply value. Driving this high-impedance input with a voltage reference within the valid range sets a target for the internal VCM error amplifier. If floated to obtain a default midsupply reference for VOCM, an external decoupling capacitor must be added on the VOCM pin to reduce the otherwise high output noise for the internal high-impedance bias.