AFE88101RRUT

ADCs/DACs - Special Purpose Overview

The AFE88101RRUT is a single-channel, 16-bit digital-to-analog converter (DAC) from Texas Instruments designed for low-power sensor-transmitter applications. It operates with a quiescent current of 170 µA (typical) and supports supply voltages as low as 1.71 V. The device integrates a 1.25-V voltage reference with 10 ppm/°C drift, a 12-bit diagnostic ADC operating at 3.84 kSPS, and an internal 1.2288-MHz oscillator. It features SPI and UART interfaces, CRC error checking, and a windowed watchdog timer for functional safety. The component is housed in a 24-pin UQFN package.

ADCs/DACs - Special Purpose Feature Summary

• 16-bit monotonic DAC with 4-LSB INL and 0.07% FSR maximum total unadjusted error (TUE).
• Integrated 12-bit, 3.84-kSPS diagnostic ADC for self-health checks of bias sources, regulators, and temperature.
• Low power consumption: 170 µA typical quiescent current at 1.8 V supply.
• Supports SPI and UART digital interfaces with CRC bit error checking and alarm notification capabilities.

ADCs/DACs - Special Purpose Applications

• 2-wire loop-powered sensor transmitters
• Process control and industrial automation systems
• Smart transmitters requiring intrinsic safety considerations
• PLC or DCS I/O modules

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific ordering suffix RRUT corresponds to the 24-pin UQFN package configuration. Confirm that external voltage-to-current conversion circuitry is included in the design, as the AFE88101 provides only the voltage output required for loop-powered transmitter architectures.

ADCs/DACs - Special Purpose Selection Notes

Select the AFE88101RRUT when 16-bit resolution is required for high-accuracy applications. Ensure the system design accommodates the 1.71 V to 5.5 V supply range and utilizes the integrated 1.25-V reference or an external source via the VREFIO pin. Verify compatibility with SPI or UART communication protocols based on the host controller interface.

ADCs/DACs - Special Purpose Part Context

The AFE88101 belongs to the AFEx8101 family, which also includes the 14-bit AFE78101. Both devices share identical pinouts, interfaces, and peripheral integrations, differing primarily in DAC resolution. This family is specifically engineered to minimize external component count in 4-mA to 20-mA loop-powered transmitter designs.

ADCs/DACs - Special Purpose Replacement Considerations

AFE78101RRUT offers 14-bit resolution with identical packaging and functionality.

ADCs/DACs - Special Purpose FAQ

What is the function of the POL_SEL/AIN1 pin?

This pin serves as an ADC input if enabled via configuration registers. Otherwise, it acts as ALMV_POL, setting the polarity of the VOUT alarm voltage.

How does the device handle fault detection?

The device uses a diagnostic ADC, CRC frame-error checking, and a windowed watchdog timer to detect faults. Upon detection, it can issue an interrupt or enter a fail-safe state corresponding to standard NAMUR values.

What are the recommended decoupling capacitance values for VDD?

A capacitor between 1 µF and 10 µF is recommended for VDD decoupling.