ZSC31150

Fast Automotive Sensor Signal Conditioner

Data Sheet

August 31, 2010

© 2010 Zentrum Mikroelektronik Dresden AG — Rev. 1.07

All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, or used without

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notice.

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ulation

t

2.6.

Analog Output AOUT

n

ut the analog signal conditioning result and for “End of Line” communication

ication is enabled

ation is disabled

500ms in maximum,

indow



WIANA:

in maximum,

indow,

ed)

The a

output p

a 12.4bit

2.7.

Serial Digital Interface

S

igital interface (SIF), which is used for communication with the circuit to

C31150 Functional Description' for a detailed description of the serial interfaces and communication

2.8.

Failsafe Features, Watchdog and Error Detection

alized by changing the internal status

hdog oversees the continuous working of the CMC and the running measurement loop. The operation

mparators watching the input

M- and register content - are watched

the sensor up to 90%. The temperature calibration includes first and second order correction and

should be fairly sufficient in all relevant cases. ADC resolution influences also calibration

possibilities – 1 bit more resolution reduces calibration range by approximately 50%. Calc

input data width is in maximum 14bit. 15 & 16bit ADC resolution mode uses only a 14 bit segmen

of ADC range.

The a alog output is used for outp

via the ZACwire

modes of the analog output in combination with OWI behavior:



OWIENA:

analog output is deactivated, OWI commun



OWIDIS:

analog output is active (~2ms after power on), OWI communic



OWIWIN:

analog output will be activated after time window,

OWI communication is enabled in time window of ~

transmission of “START_CM” command has to be finished during time w

O

analog output will be activated after ~2ms power on time,

OWI communication is enabled in time window of ~500ms

transmission of “START_CM” command has to be finished during time w

to communicate the internal driven potential at AOUT has to be overwritten

by the external communication master (AOUT drive capability is current limit

nalog

otential is driven by a unity gain output buffer, those input signal is generated by

resistor string DAC. The output buffer (BAMP) – a rail-to-rail OPAMP - is offset compensated and current

limited. So a short circuit of analog output to ground or power supply does not damage the ZSC31150.

The Z C31150 includes a serial d

realize calibration of the sensor module. The serial interface is able to communicate with two communication

protocols – I²C

used to realize an “End of Line” calibration via the analog output AOUT of the complete assembled sensor

module.

Refer 'ZS

protocols.

The ZSC31150 detects various possible errors. A detected error is sign

in diagnostic mode (DM). In this case the analog output is set to LOW (minimum possible output value = lower

diagnostic range – LDR) and the output registers of the digital serial interface are set to a significant error

code.

A watc

of the internal clock oscillator is verified continuously by oscillator fail detection.

A check of the sensor bridge for broken wires is done permanently by two co

voltage of each input (sensor connection and short check). Additionally the common mode voltage of the

sensor and sensor input short is watched permanently (sensor aging).

Different functions and blocks in digital part - like RAM-, ROM-, EEPRO

continuously. Refer 'ZSC31150 Functional Description' for a detailed description of safety features and

methods of error messaging.