ZHCSRW7 march 2023 AFE781H1 , AFE881H1
PRODUCTION DATA
The AFEx81H1 are extremely low-power 16-bit and 14-bit voltage output DACs. The DACs support a low output range of 0.15 V to 1.25 V or a high output range of 0.3 V to 2.5 V. These devices have an onboard oscillator and an optional precision internal reference. Use these output values with a voltage-to-current (V-to-I) converter stage for 4-mA to 20-mA, loop-powered applications. These devices also feature a SAR ADC that is used to measure internal and external nodes for making diagnostic measurements with fault detection and alarm actions. Use these diagnostic measurements together with the CRC and watchdog timer monitoring for device and system monitoring for functional safety.
The AFEx81H1 devices support modem functionality with the Highway Addressable Remote Transducer (HART) Protocol through SPI or UART communications. To create a field transmitter, a HART interface is created through modulation and demodulation using the SPI or UART. Demodulate the input through band-pass filtering internal or external to the device.
The AFEx81H1 can operate using extremely low power with 1.8-V supplies. For low-voltage operation, use PVDD with a 1.8-V nominal supply and an operating range of 1.71 V to 1.89 V. Run the digital interface supply, IOVDD, from 1.71 V to 5.5 V. During low-voltage operation, the VDD LDO is automatically disabled and VDD is tied to PVDD. Low-voltage operation allows for both lower power for field transmitter applications and better voltage compliance when there are high resistances in the loop.
With higher-supply operation, the PVDD has an operating range of 2.7 V to 5.5 V. With this range of operation, the VDD is powered from an onboard LDO.