SBAS813 June 2018 ADS8688AT
PRODUCTION DATA.
The ADS8688AT is a 16-bit data acquisition system with 8-channel analog inputs. Each analog input channel consists of an overvoltage protection circuit, a programmable gain amplifier (PGA), and a second-order, antialiasing filter that conditions the input signal before being fed into an 8-channel analog multiplexer (MUX). The output of the MUX is digitized using a 16-bit analog-to-digital converter (ADC), based on the successive approximation register (SAR) architecture. This overall system can achieve a maximum throughput of 500 kSPS, combined across all channels. The device features a 4.096-V internal reference with a fast-settling buffer and a simple SPI-compatible serial interface with daisy-chain (DAISY) and ALARM features.
The device operates from a single 5-V analog supply and can accommodate true bipolar input signals up to ±2.5 × VREF. The device offers a constant 1-MΩ resistive input impedance irrespective of the sampling frequency or the selected input range. The integration of multichannel precision analog front-end circuits with high input impedance and a precision ADC operating from a single 5-V supply offers a simplified end solution without requiring external high-voltage bipolar supplies and complicated driver circuits.