GENERAL DESCRIPTION

The AD7175-2 is a low noise, fast settling, multiplexed, 2-/4-channel (fully/pseudo differential) Σ-Δ analog-to-digital converter (ADC) for low bandwidth inputs. It has a maximum channel scan rate of 50 kSPS (20 µs) for fully settled data. The output data rates range from 5 SPS to 250 kSPS.

FEATURES

Fast and flexible output rate: 5 SPS to 250 kSPS

Channel scan data rate of 50 kSPS/channel (20 µs settling)

Performance specifications

17.2 noise free bits at 250 kSPS

20 noise free bits at 2.5 kSPS

24 noise free bits at 20 SPS

INL: ±1 ppm of FSR

85 dB rejection of 50 Hz and 60 Hz with 50 ms settling

User configurable input channels

2 fully differential channels or 4 single-ended channels

Crosspoint multiplexer

On-chip 2.5 V reference (±2 ppm/°C drift)

True rail-to-rail analog and reference input buffers

Internal or external clock

Power supply: AVDD1 = 5 V, AVDD2 = IOVDD = 2 V to 5 V

Split supply with AVDD1/AVSS at ±2.5 V

ADC current: 8.4 mA

Temperature range: −40°C to +105°C

3- or 4-wire serial digital interface (Schmitt trigger on SCLK)

Serial port interface (SPI), QSPI, MICROWIRE, and DSP

compatible

APPLICATIONS

Process control: PLC/DCS modules

Temperature and pressure measurement

Medical and scientific multichannel instrumentation

Chromatography