UM0526 Datasheet, PDF (1/9 Pages) STMicroelectronics – proximity sensor board based on TDA0161

UM0526
User manual
STEVAL-IFS007V1 4-channel
proximity sensor board based on TDA0161
Introduction
This user manual explains the STEVAL-IFS007VA which has been designed to be easy to
plug into 24 V operated systems as it is usually implemented in factory automation
environments.
The document shows the STEVAL-IFS007V1 demonstration kit (hereafter also called “proxy
board”) features, its technical characteristics and then, as an optional feature, the
connectivity to the CLT3-4BT6 board (a board hosting a current-limited overvoltage-
protected quad digital termination). Finally, a detailed illustration of an application example is
also given. The STEVAL-IFS007V1 can be considered a system end-board. It could be
placed as a standalone in systems where no processing or control characteristics are
required or it could be integrated as an end board in control systems, in which case an
interface board like the CLT3-4BT6 previously mentioned is necessary to protect the
microcontroller and other application specific devices from high current and voltages out of
their specifications. When the board is used as a standalone, it is possible to connect up to
4 different and independent coils. Each coil acts as the passive element able to sense an
incoming metallic object by sensing variations in high frequency eddy current losses. The
TDA0161 proximity detector changes its output signal as a consequence of a supply current
change. In fact, independently of the supply voltage provided, this current is high (or low)
according to the presence (or absence) of a closely located metallic object, consequently
the output voltage level corresponding to that channel changes coherently. In terms of
output voltage, the variation is between ~8.5 V and 11.5 V in a 24 V supplied system, so the
output span is about 3 V. On-board jumpers are placed in order to enable/disable channels.
Also on-board LEDs are placed to furnish a local alert when an object is close to a coil. At
this end, the circuit parameters are tuned in order to detect metallic objects at a distance up
to 4 mm. For further details on parameter tuning and on the circuit and device functionality,
please refer to the TDA0161 device datasheet.
Figure 1. The STEVAL-IFS007V1 board
March 2008
Rev 1
1/9
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