ZHCSI16F March 2002 – April 2018 OPA2357 , OPA357
PRODUCTION DATA.
The OPA357 enable function is implemented using a Schmitt trigger. The amplifier is enabled by applying a TTL high voltage level (referenced to V−) to the Enable pin. Conversely, a TTL low voltage level (referenced to V−) disables the amplifier, reducing its supply current from 4.9 mA to only 3.4 µA per amplifier. Independent Enable pins are available for each channel (dual version), providing maximum design flexibility. For portable battery-operated applications, this feature can be used to greatly reduce the average current and thereby extend battery life.
The Enable input can be modeled as a CMOS input gate with a 100-kΩ pull-up resistor to V+. Connect this pin to a valid high or low voltage or driven, not left open circuit.
The enable time is 100 ns and the disable time is only 30 ns. This time allows the OPA357 to be operated as a gated amplifier, or to have its output multiplexed onto a common output bus. When disabled, the output assumes a high-impedance state.