AFE882H1RRUR

Analog Front End (AFE) Overview

The AFE882H1 is a 16-bit digital-to-analog converter (DAC) with an integrated HART modem, voltage reference, and diagnostic ADC. It features a 0 V to 2.5 V output range, 4-LSB INL at 16 bits, and 0.07% FSR total unadjusted error from –40°C to +125°C. The device includes a 12-bit 3.84-kSPS diagnostic ADC, a 1.25-V internal reference (10 ppm/°C), and a 1.2288-MHz oscillator. Quiescent current is 180 µA typical. It supports SPI and UART interfaces for DAC and HART communication, offering fault detection via CRC, watchdog timer, and diagnostic checks.

Analog Front End (AFE) Feature Summary

• 16-bit monotonic DAC with 4-LSB INL and 0.07% FSR TUE over temperature
• Integrated HART-compliant physical layer modem with programmable TX amplitude
• 12-bit 3.84-kSPS diagnostic ADC for self-health checks of bias sources, regulator, and temperature
• Low quiescent current of 180 µA typical with 1.25-V internal voltage reference

Analog Front End (AFE) Applications

• Process control and industrial automation systems
• PLC or DCS I/O modules
• 3-wire and 4-wire transmitters
• 4-mA to 20-mA loop-powered applications

Analog Front End (AFE) Procurement Notes

Verify the specific ordering suffix RRUR corresponds to the UQFN 24-pin package. Confirm functional safety documentation availability if required for system design. Ensure external voltage-to-current conversion and power regulation components are included in the design, as the AFE882H1 provides only the analog front-end functions.

Analog Front End (AFE) Selection Notes

Select the AFE882H1 for 16-bit resolution requirements; use the AFE782H1 for 14-bit applications. Verify that the 0 V to 2.5 V DAC output range meets the downstream circuit requirements. Ensure the IOVDD supply voltage (1.71 V to 5.5 V) matches the host controller logic levels. Check thermal resistance RθJA of 103.1 °C/W for PCB layout planning.

Analog Front End (AFE) Part Context

The AFE882H1 is part of the AFEx82H1 family, which also includes the 14-bit AFE782H1. Both devices share the same RRU (UQFN, 24) package and pinout. The primary distinction is the DAC resolution: 16 bits for the AFE882H1 and 14 bits for the AFE782H1. They are designed for HART-enabled process control applications requiring high accuracy and low power consumption.

Analog Front End (AFE) Replacement Considerations

The AFE782H1 is a compatible alternative within the same family, offering 14-bit resolution instead of 16-bit. It shares the same package, pinout, and peripheral integration. No other direct substitutes are documented in the provided datasheet.

Analog Front End (AFE) FAQ

What is the maximum capacitive load supported by the MOD_OUT pin?

The MOD_OUT pin supports a maximum parallel load capacitance of 2 nF.

How does the REF_EN pin affect the VREFIO pin?

When REF_EN is logic high, the internal VREF is enabled, and the VREFIO pin outputs 1.25 V. When logic low, the internal reference is disabled, and an external 1.25-V reference must be applied to the VREFIO pin.

What is the function of the RTS pin?

The RTS (Request to Send) pin controls the HART modem direction. Logic high enables the demodulator and disables the modulator. Logic low enables the modulator and disables the demodulator.