Dallas, Texas: The four-channel ADS8634 and eight-channel ADS8638 bipolar 12-bit successive approximation register (SAR) analogue-to-digital converters (ADCs) from Texas Instruments boast a 1-Msample/s sampling rate that’s a fourfold improvement over the company’s previous generation of ADCs (see the figure). The devices are intended for programmable logic control (PLC) and data acquisition applications.
The ADS8634 and ADS8638 provide a wide operating temperature range, up to 125°C, and are fully characterised over the extended industrial temperature range. They also allow an input range of ±12 V when used with an external reference. The digital interface supports 1.8- to 5-V hosts without additional level shifting circuitry.
Both ADCs feature per-channel software-selectable input ranges that support ±12 V, ±10 V, ±5 V, ±2.5 V, 0 to 5 V, and 0 to 10 V, providing a single-chip solution for a wide range of inputs, while enabling designers to easily interface to a variety of sensors with a single ADC.
TI offers a host of tools and support to speed development with the ADS8634 and ADS8638, including an IBIS model, an anti-aliasing filter tool for data converters, and an op-amp-to-ADC circuit topography calculator. A performance development kit, including all circuitry, software, and source code, is also available to evaluate the performance of both parts.