AFE881H1开发板套件编程器的评估板-数模转换器（DAC）规格书PDF中文资料

AFE881H1属于开发板套件编程器的评估板-数模转换器（DAC）。由德州仪器制造生产的AFE881H1评估板 - 数模转换器（DAC）该系列产品提供了一种方便的方法，在经过验证的设计环境中对用于将数字数据转换为模拟格式的器件进行性能或特性评估。重点器件涵盖范围从以适合学生或爱好者使用的方式实现的适度功能器件，到适合电信基础设施应用的高级器件。

1 Features

• Functional Safety-Capable

– Documentation available to aid functional safety

system design: AFE881H1, AFE781H1

• Low quiescent current: 180 μA (typical)

• HART®-compliant physical layer modem

• 16-bit or 14-bit monotonic high-performance DAC

– 1.8-V supply: 0.15 V to 1.25 V, 0.2 V to 1.0 V

– 5-V supply: 0.3 V to 2.5 V, 0.4 V to 2.0 V

– 4-LSB INL at 16 bits

– 0.07 FSR (max) TUE from –40°C to +125°C

• 12-bit 3.84-kSPS ADC for advanced diagnostics

• Integrated 1.25-V reference at 10 ppm/°C (max)

• Internal 1.2288-MHz oscillator with clock output

• Digital interface

– Serial peripheral interface (SPI): Shared bus for

both DAC and HART

– Universal asynchronous receiver-transmitter

(UART): Shared bus for both DAC and HART

– Both: SPI for DAC and UART for HART

• Fault detection: CRC bit error checking, windowed

watchdog timer, diagnostic ADC

• Digital DAC slew-rate control

• Wide operating temperature: –55°C to +125°C

2 Applications

• 2-wire, 4-mA to 20-mA loop-powered transmitters

• Process control and industrial automation

• Smart transmitters

3 Description

The 16-bit AFE881H1 and 14-bit AFE781H1

(AFEx81H1) are highly-integrated, high-accuracy,

extremely low-power digital-to-analog converters

(DACs) with voltage outputs designed for HARTenabled

sensor-transmitter applications.

The AFEx81H1 devices include most of the

components required to design a 4‑mA to

20‑mA, 2‑wire (loop-powered) sensor transmitter. In

addition to the highly accurate DAC, these parts

include a HART-certified FSK modem, 10‑ppm/°C

voltage reference, and diagnostic analog-to-digital

converter (ADC). To accommodate intrinsic and

functional safety concerns, external voltage-to-current

conversion and power regulation are required.

The internal diagnostic ADC is multiplexed to several

internal nodes that enable an automatic self-health

check. If any fault is detected from the diagnostic

ADC, CRC frame-error checking, or windowed

watchdog timer, the devices can optionally issue

an interrupt, enter a fail-safe state corresponding to

a standard NAMUR output value or user-specified

custom value, or both.

These devices operate from supplies as low as 1.71 V

with 220 μA maximum quiescent current. The devices

are specified over the temperature range of –40°C to

+125°C, but are functional from –55°C to +125°C.