1 Features

1• Small package size:

– WQFN 3 mm × 3 mm

• 8 channels configurable as any combination of:

– Up to 8 analog inputs, digital inputs, or digital

outputs

• GPIOs for I/O expansion:

– Open-drain, push-pull digital outputs

• Analog watchdog:

– Programmable thresholds per channel

– Event counter for transient rejection

• Wide operating ranges:

– AVDD: 2.35 V to 5.5 V

– DVDD: 1.65 V to 5.5 V

– –40°C to +85°C temperature range

• Enhanced-SPI digital interface:

– High-speed, 60-MHz interface

– Achieve full throughput with >13.5-MHz SPI

• CRC for read/write operation:

– CRC on data read/write

– CRC on power-up configuration

• Programmable averaging filters

• Root-mean-square module:

– 16-bit true RMS output

– Programmable RMS time window

• Zero-crossing-detect module:

– ZCD output corresponding to analog input

– Built-in transient rejection and hysteresis

– Digitally adjustable detection threshold

2 Applications

• Refrigerator and freezer

• Rack server

• Mixed module (AI, AO, DI, DO)

• AC drive power stage module

3 Description

The ADS7028 is an easy-to-use, 8-channel,

multiplexed, 12-bit, 1-MSPS, successive

approximation register analog-to-digital converter

(SAR ADC). The eight channels can be

independently configured as either analog inputs,

digital inputs, or digital outputs. The device has an

internal oscillator for the ADC conversion process.

The ADS7028 communicates through an SPIcompatible

interface and operates in either

autonomous or single-shot conversion mode. The

ADS7028 implements the analog watchdog function

by event-triggered interrupts per channel using a

digital window comparator with programmable high

and low thresholds, hysteresis, and an event counter.

The ADS7028 has a built-in cyclic redundancy check

(CRC) for data read/write operations and the powerup

configuration. The ADS7028 features a root-meansquare

(RMS) module that computes a 16-bit true

RMS result for any analog input channel. The

integrated zero-crossing-detect (ZCD) module allows

for transient rejection and hysteresis near the

configurable threshold crossings.