Signal conditioning

Among the most used electronic components in modern cars are sensors. Since they are omnipresent, they came into focus for space saving. Most (analogue) sensing components can’t shrink much but the ‘back end’ like signal conditioning can.

One approach toward shrinking sensor electronics has just been realized by ZMD (Zentrum Mikroelektronik Dresden), a Dresden-based supplier of energy-efficient analogue and mixed-signal solutions for automotive, industrial, and medical applications. The single-chip »ZSSC3170« for resistive bridge sensors combines a sensor conditioning IC with a LIN transceiver and is designed for direct 12V supply provided by the vehicle power system. The idea is to develop a complete sensor application with a single IC, save component costs and board space. Typical targeted applications are in air-conditioning, level measurement and seat adjustment - in short comfort applications that require an integrated LIN interface.
“The small size of the ZSSC3170 and the robust LIN interface help designers to reduce system space and cost,” stated Steve Ramdin, SSC Product Manager. »By the combination of LIN and sensor signal conditioning in one IC only the sensor element and a few passive components are needed to develop a complete sensor application.«

The integrated LIN transceiver meets the LIN specifications 1.3, 2.0 and 2.1 and has an EMC immunity of up to ±8kV. Since the ZSSC3170 is designed for harsh automotive environments, it incorporates special protection circuitry, electromagnetic compatibility and numerous diagnostic features. The device can be calibrated in-system where coefficients are stored in on-chip automotive-grade EEPROM. With ZMDI’s single-pass calibration technique, no external trimming components are required.
The ZSSC3170 operates on supply voltages from 7V to 18V and over a temperature range of -40°C to +125°C, or extended up to +150°C. Accuracy is ±0.25% FSO over a temperature range of -20°C to +85°C, ±0.50% FSO at -40°C to 125°C and ±1.00% FSO at -40°C to 150°C. The IC comes as die or in a SSOP20 package.
The ZSSC3170 development kit includes a development board, samples and software for quick and easy evaluation and support for calibrating prototypes. Application notes are available for download. Samples are available now. Packaged parts are priced at €2.30 in low quantities.