Functional Description

Functional Description
Rev. 1.07 / June 2014
ZSC31150
Fast Automotive Sensor Signal Conditioner
Multi-Market Sensing Platforms
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Contents
1
2
3
4
5
Control Logic .....................................................................................................................................................5
1.1. General Description ....................................................................................................................................5
1.2. CMC Description ........................................................................................................................................5
1.3. General Working Modes .............................................................................................................................5
1.3.1. Normal Operation Mode (NOM) ...........................................................................................................6
1.3.2. Command Mode (CM) .........................................................................................................................6
1.3.3. Diagnostic Mode (DM), Failsafe Tasks, and Error Codes ...................................................................6
Signal Conditioning ...........................................................................................................................................9
2.1. AD Conversion............................................................................................................................................9
2.2. AD Conversion Result Segmentation .......................................................................................................10
2.3. Signal Conditioning Formula ....................................................................................................................11
2.4. Analog and Digital Output .........................................................................................................................12
2.5. Digital Filter Function ................................................................................................................................12
2.6. Output Signal Range and Limitation .........................................................................................................13
Serial Digital Interface (SIF) ............................................................................................................................14
3.1. General Description ..................................................................................................................................14
3.1.1. Addressing .........................................................................................................................................14
3.1.2. Communication Verification ...............................................................................................................15
3.1.3. Communication Protocol Selection ....................................................................................................15
2
3.2. I C™ Protocol ...........................................................................................................................................15
3.3. Digital One-Wire Interface (OWI)..............................................................................................................19
Interface Commands .......................................................................................................................................23
4.1. Command Set ...........................................................................................................................................23
4.2. Command Processing ..............................................................................................................................26
4.3. SIF Output Registers ................................................................................................................................26
4.4. Command Response Codes ....................................................................................................................27
4.5. Detailed Description for Specific Commands ...........................................................................................28
4.5.1. START_CM (72D1HEX) .......................................................................................................................28
4.5.2. START_AD_CNT (62HEX) ...................................................................................................................28
4.5.3. ADJ_OSC_ACQ (50HEX) and ADJ_OSC_WRI (65xxxxHEX) ...............................................................29
EEPROM and RAM .........................................................................................................................................31
5.1. Programming the EEPROM .....................................................................................................................31
5.2. EEPROM and RAM Content ....................................................................................................................31
5.2.1. Traceability .........................................................................................................................................33
5.2.2. Configuration Words ..........................................................................................................................34
5.3. EEPROM Signature ..................................................................................................................................37
5.4. EEPROM Write Locking ...........................................................................................................................38
Functional
Description
June 30, 2014
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
6
Temperature Sensor Adaption and CMV Measurement .................................................................................38
6.1. Temperature Measurement when Sensor Bridge is in Voltage Excitation Mode .....................................39
6.1.1. Internal PN-Junction TS .....................................................................................................................39
6.1.2. External PN-Junction TS ....................................................................................................................39
6.1.3. External Resistor ................................................................................................................................40
6.1.4. Result and Sensitivity Calculation ......................................................................................................41
6.2. Temperature Measurement when Sensor Bridge in Current Excitation Mode .........................................42
6.3. CMV Measurement ...................................................................................................................................43
6.4. Sensor Check ...........................................................................................................................................44
7 Related Documents .........................................................................................................................................45
8 Glossary ..........................................................................................................................................................45
9 Document Revision History .............................................................................................................................47
List of Figures
Figure 1.1
Figure 2.1
Figure 3.1
Figure 3.2
Figure 3.3
Figure 3.4
Figure 3.5
Figure 3.6
Figure 3.7
Figure 3.8
Figure 3.9
Figure 4.1
Figure 4.2
Figure 5.1
Figure 6.1
Figure 6.2
Figure 6.3
Figure 6.4
Functional
Description
June 30, 2014
Modes of Digital Serial Communication ...............................................................................................6
Accessible Output Signal Range and Limitation ................................................................................13
2
I C™ – Principles of Protocol ............................................................................................................15
I²C™ – Write Operation .....................................................................................................................16
I²C™ – Read Operation – Data Request ...........................................................................................17
I²C™ – Timing Protocol .....................................................................................................................18
Block Diagram of the OWI Connection ..............................................................................................19
OWI – Stop Condition for Active Driven AOUT .................................................................................21
OWI – Write Operation ......................................................................................................................21
OWI – Read Operation – Data Request ............................................................................................22
OWI – Timing Protocol .......................................................................................................................22
Preventing Misinterpretation of CRC .................................................................................................26
START_CM Command ......................................................................................................................28
Source-Code Signature Generation ..................................................................................................37
External PN-Junction Temperature Sensor .......................................................................................39
Temperature Measurement with External Resistor ...........................................................................40
Bridge Current Mode Application .......................................................................................................42
Principle of Sensor Short Check ........................................................................................................44
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
List of Tables
Table 1.1
Table 2.1
Table 3.1
Table 3.2
Table 3.3
Table 4.1
Table 4.2
Table 4.3
Table 4.4
Table 4.5
Table 4.6
Table 5.1
Table 5.2
Table 5.3
Table 5.4
Table 5.5
Table 5.6
Table 6.1
Table 6.2
Table 6.3
Table 6.4
Table 6.5
Table 6.6
Table 6.7
Functional
Description
June 30, 2014
Error Codes..........................................................................................................................................8
Valid Data Ranges for 15-bit and 16-bit ADC Resolution ..................................................................10
2
Timing I C™ Protocol ........................................................................................................................18
OWI Interface Parameters .................................................................................................................20
OWI Timing Protocol ..........................................................................................................................23
Command Set ....................................................................................................................................24
Output Register Contents of Serial Digital Interface (SIF) When Processing Commands ................27
Command Response: First Readout Word (SIF Output Register 1) .................................................27
START_AD_CNT – Data Word Description ......................................................................................29
START_AD_CNT – Command Response Description......................................................................29
Oscillator Frequency Adjustment Sequence / Tasks (OWI Only) ......................................................30
EEPROM and RAM Content ..............................................................................................................31
Lot, Wafer, x-Position, and y-Position Number Calculation Procedure .............................................33
Configuration Word CFGAFE ............................................................................................................34
Configuration Word CFGAPP ............................................................................................................35
Configuration Word ADJREF .............................................................................................................36
Configuration Word RESERVED .......................................................................................................37
Configuration Temperature Measurement .........................................................................................38
Sensitivity Internal Temperature Sensor ...........................................................................................39
Sensitivity and IRTEMP Input Signal Range in mV/V using External PN-Junction Mode .................39
Temperature Measurement Input Range Midpoint in mV (RMED) .....................................................40
ZSC31150 Input Signal Range for External Resistor Mode (Voltages referenced to VDDA) ...........41
Temperature Gain Coefficients ..........................................................................................................41
Temperature Measurement in Bridge Current Excitation Mode (CFGAPP:CSBE=1) .......................42
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
1
Control Logic
1.1.
General Description
The control logic of the ZSC31150 consists of the calibration microcontroller (CMC) and the control logic modules
of the analog-to-digital (A/D) converter and serial digital interface. The configuration of the various modes of the
device is done by programming an EEPROM.
The CMC controls the measurement cycle and performs the calculations for sensor signal conditioning. This
eliminates the gain deviation, the offset, the temperature deviation, and the non-linearity of the pre-amplified and
A/D-converted sensor signal.
Communication between the ZSC31150 and an external microcontroller, especially for calibration purposes, is
2
*
done via a serial digital interface. Communication protocols according to the I C™ standard are supported. A
one-wire interface called OWI with the brand name ZACwire™ is also implemented. These serial interfaces are
used for calibration of the sensor system consisting of a sensor transducer and the ZSC31150. The serial
interface provides the read-out of the results of sensor signal conditioning as digital values during the calibration.
The internal processing of received interface commands is done by the CMC. Therefore, the measurement cycle
is interrupted if a command is received. Only the read-out of data is controlled by the serial interface itself and
does not interrupt the CMC.
The controller of the A/D conversion is started by the CMC and executed as a continuous measurement cycle.
The conditioning calculation by the CMC works in parallel to the A/D conversion.
1.2.
CMC Description
The CMC is especially adapted to the tasks connected with the signal conditioning.
The main features are



1.3.
16-bit processing width and programming via ROM.
Constants/coefficients for the conditioning calculation stored in the EEPROM. After power-on or after
re-initialization from EEPROM by sending a specific command to the serial interface, the EEPROM is
mirrored to the RAM.
Continuous parity checking during every read from RAM. If incorrect data is detected, the diagnostic mode
(DM) is activated (an error code is written to the serial digital output; the analog out is set to the diagnostic
level).
General Working Modes
The ZSC31150 supports three different working modes:
 Normal Operation Mode (NOM)
 Command Mode (CM)
 Diagnostic Mode (DM)
The command set includes commands for changing the working mode. Refer to section 4 for a detailed description of these commands.
* I2C™ is a trademark of NXP.
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Description
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© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
1.3.1. Normal Operation Mode (NOM)
The NOM is the recommended working mode for applications. After power-on, the ZSC31150 starts with an
initialization routine, and the NOM will be activated after this.
During the initialization routine, first the EEPROM is mirrored to the RAM, which checks the EEPROM content. If
an error is detected, the DM is activated. The configuration of the ZSC31150, which is stored in the EEPROM, is
consecutively set.
Next the continuous measurement cycle and the conditioning calculation start. The signal conditioning result is
refreshed with each cycle time period. This generates the analog output at the AOUT pin, and it can be read via
the serial digital Interface (SIF) as a digital output.
Provided that the EEPROM is programmed correctly, the NOM works without the microcontroller sending any
command to the digital serial interface. Read-out of the conditioning result via the SIF is possible; this does not
interrupt continuous processing of the signal conditioning routine.
1.3.2. Command Mode (CM)
The CM is the working mode that is used for calibration data acquisition and access to the internal RAM and
EEPROM of the ZSC31150. The CM start command START_CM aborts the running NOM, so the measurement
cycle is stopped. The ZSC31150 changes to CM only after receiving the START_CM command via the digital
serial interface. This protects the ZSC31150 against interruption of processing during the NOM (= continuous
signal conditioning) and/or unintentional changes of configuration. In CM, the full set of commands is supported.
If the ZSC31150 receives a command other than START_CM in NOM, it is not valid. It will be ignored, and no
interrupt to the continuous measurement cycle will be generated. Refer to section 4.5.1 for a detailed description
of the START_CM command.
In CM, the full command set is enabled for processing. During processing of a received command, the serial
interface is disabled, and no further commands are recognized. After finishing the routine, the CMC waits for
further commands or the process loops continuously (e.g., after measurement commands).
Figure 1.1 Modes of Digital Serial Communication
Normal Operation Mode
Only SIF readout
Command: START_CM (72HEX)
Command Mode
Refer to Table 4.1 for details of the command set.
Full command set
EEPROM programming is only enabled after receiving the EEP_WRITE_EN command.
2
Starting CM via I C™ communication (SCL and SDA pins) is possible at any time. For communication via the
one-wire interface (AOUT pin), several modes can be activated in the configuration setup, e.g., the start window.
1.3.3. Diagnostic Mode (DM), Failsafe Tasks, and Error Codes
The ZSC31150 detects various possible failures, in which case the DM is activated. The DM is indicated by the
ZSC31150 setting the output pin AOUT in the lower diagnostic range (LDR) and the output registers of the digital
2
serial interface are set to a defined error code. In this case, independent from configuration, the OWI and I C™
communication is enabled, and an error code can be read out.
Because the analog output AOUT is driven LOW, the AOUT pin must be overwritten (AOUT current limitation:
< 20mA) for starting digital communication using the OWI interface. Therefore the communication master must
provide driving capability for doing this.
Functional
Description
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© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Note that the error detection functionality can be partly enabled/disabled by configuration words (e.g., sensor
connection check, sensor aging (CMV) limits, ROM check, etc.).
The failure counting sequence/procedure is called the “Temporary DM.” The DM (LDR) will be activated after two
sequential detected failure events and will be deactivated after counting down the failure counter if the failure
condition is no longer given.
Power and Ground Loss
Power and ground loss cases are indicated by pulling the AOUT pin into the lower or upper diagnostic range
(LDR/UDR) in the event of a lost node or load connection to ground or the supply. The ZSC31150 is inactive in
this case, and the specified leakage current in combination with the load resistor guarantees reaching the LDR or
UDR.
Temperature Sensor Check *
The temperature sensor check monitors whether the ADC exceeds lower or upper temperature limits.
Possible causes of failure are
 The external temperature sensor is unconnected.
 The offset of the temperature measurement (ADJREF:TOFFS) is not sufficiently adjusted; signal is out of
the ADC range.
RESOLUTION
The temperature raw value (T) is checked to determine if it is equal 0 or if it is greater or equal to (2
- 1).
16/15 bit raw values are shifted to 14/13 bits before the check. The temperature sensor (TS) check uses the
failure counter sequence (i.e., temporary DM).
*
Note: The Temperature Sensor Check is only available for ZSC31150Dxx and subsequent versions.
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Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 1.1
Error Codes
Note: In the case of detection of different failures with the code “C0xxHEX,” the codes are “OR” combined. If any signature or
configuration error occurs, it is overwritten if there is a watchdog error at the watchdog timeout.
Failsafe Task
Description
Messaging Time
Error
Code
Deactivation
Action
Oscillator Fail (OFC)
Detects faulty oscillator operation
< 200µs
-
No
Temporary
DM
Watchdog Timeout
(WDG)
Detection of watchdog timeout of
start routine or measurement cycle
Always
C008
No
DM or Reset
RAM Parity (RAP)
Parity check at every RAM access
Without Delay
C001
No
DM or Reset
Without Delay
C002
No
DM or Reset
Register Parity (RGP) Permanent parity check of
configuration registers
EEPROM Multi-bit
(EMC)
Detection of non-correctable multi-bit
error per 16-bit word
Start Up
C004
No
DM
EEPROM Signature
(ECS)
Signature check during read out of
EEPROM after power-on or after
START_CYC_EEP* command
Start Up
C0AA
No
DM
ROM Signature
(RSC)
ROM signature check at power-on
(enabled by CFGAPP:CHKROM;
needs approximately 10ms additional
startup time)
Start Up
C0CC
Yes
DM
Only for product
codes ZSC31150Ex
and earlier:
Detects digital averaging filter
coefficients failure, analog output
limits out of addressable range, or
undefined command in CM
Start Up /
Command Received
C0FF
No
DM
DM or Reset
Inconsistent
Configuration (ICC)
Arithmetic Check
(ACC)
Functional check of arithmetic unit
during measurement cycle
C010
No
SCC
Sensor connection check
(enabled by CFGAPP:CHKSENS)
C010
Yes
Temperature Sensor
(TS) Check
Temperature sensor AD conversion
result check = 0HEX or (2RESOLUTION – 1)
C010
Yes
SSC (P/N)
Sensor short check positive/negative
biased
(enabled by CFGAPP:CHKSENS)
C010
Yes
Sensor Aging (CMV)
Compares sensor bridge common
mode voltage to programmed limits
(disabled by register AHEX = FF00HEX
setting)
C010
Yes
Power & Ground
Loss (PGL)
Power and ground loss detection; in
the event of PGL, the output is pulled
into the LDR or UDR by an external
pull resistor
-
No
Functional
Description
June 30, 2014
Processed once per
cycle, so message
time is a minimum of
2 cycles.
<5ms
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
Temporary
DM
(temporary
diagnostic
mode)
Reset
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ZSC31150
Fast Automotive Sensor Signal Conditioner
2
Signal Conditioning
2.1.
AD Conversion
During NOM, the analog preconditioned sensor signal is continuously converted by the ADC. The A/D conversion
is configurable for resolution rADC and the inherent range shift RSADC by the configuration word CFGAFE (see
Table 5.3).The one or two step conversion mode is selectable. The two-step mode is faster; the one-step mode is
more accurate because of the longer integration time. The selected resolution for the A/D conversion is equal for
all measurements in the measurement cycle (e.g., input voltage, temperature, auto-zero, etc.). The resulting
digital raw values for the measured value (e.g., pressure) and temperature are determined by the following
equations:
 Analog differential input voltage
to A/D conversion
Measured value VIN_DIFF to be conditioned:
VADC_DIFF  aIN VIN_DIFF  aXZC VXZC
VIN_DIFF
Differential voltage input to analog front-end
VOFF
Residual offset voltage of analog front-end (which
is eliminated by ZADC – ZAZ difference calculation)
VXZC
Extended zero compensation voltage (refer to the
ZSC31150 Data Sheet for details):

 3 PXZCPOL  2
VXZC  VADC _ REF  PXZC
48

 Digital raw A/D conversion result:
 VADC_DIFF  VOFF

Z ADC  2 rADC 
 1  RS ADC 


VADC_REF


Z AZ
aIN
Gain of analog front-end for differential
input voltage (see Table 5.3)
aXZC
Gain of extended zero compensation voltage
(refer to the ZSC31150 Data Sheet for details)
VADC_DIFF
Differential input voltage to A/D converter
VADC_REF
ADC reference voltage (ratiometric reference for
measurement)
rADC
Resolution of A/D conversion
RSADC
Range shift of A/D conversion:
7
15
Bridge Sensor Measurement: ½, ¾, /8, /16
Temperature Measurement: ½ (see section 6)
 Auto-zero corrected raw A/D conversion result:
V
ZCORR  Z ADC  Z AZ  2rADC  ADC_DIFF
 VADC_REF

Functional
Description
June 30, 2014






(PXZC and PXZCPOL are bit fields in register
CFGAFE.)
 Auto-zero value:
 VOFF

 2 rADC 
 1  RSADC 
V

 ADC_REF

 
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
2.2.
AD Conversion Result Segmentation
The result of the AD conversion ZCORR, which is the input value for the signal conditioning formula, depends on the
resolution adjustment rADC ranging from 13 to 16 bit resolution. Raw values acquired with resolutions of 15 and 16
bits must be mapped to the 13 or 14 bit resolution range for further calculations. This is done by different methods
depending on the data to be measured:



CMV, SSC+, and SSC- measurements for diagnostic checks are always shifted to 13 bits.
The temperature measurement data (ZCORR_T) are divided by 4.
15
The bridge sensor (BR) measurement auto-zero corrected data (ZCORR) must be moved in the +/- 2 range
(see Table 2.1) by subtraction of the offset determined in configuration register CFGAPP:POFFS (see
Table 5.4). Minimum and maximum input data (span of ZCORR raw data) should have 14-bit or slightly higher
resolution (16384 ADC counts) for proper calibration coefficients calculation.
AD conversion result segmentation calculation (only if rADC = 15 or 16 bit)
ZCORR_OUT  ZCORR  POFFS 2
13
rADC
ZCORR
ZCORR_OUT
with POFFS  [0; 7]
ZCORR_T
ZCORR_TOUT 
ZCORR_TOUT
ZCORR_T
Resolution of AD conversion in bits
Raw input main channel A/D result for measured value
(auto-zero compensated; D8HEX and D9HEX commands)
Raw main channel A/D result for measured value (autozero compensated), mapped in range given in Table 2.1
Raw temperature input A/D result for measured value
(auto-zero compensated)
Raw temperature A/D result for measured value (auto-zero
14
14
compensated), mapped in range [-2 ; 2 )
4
Note: All raw data acquiring commands (Dx commands listed in Table 4.1) do not process the shifting
procedure, and therefore 15 and 16 bit results are read out. Therefore the acquired data must be processed
according to the ZCORR_OUT and ZCORR_TOUT formulas above in the following sequence before calculation of the
calibration coefficients:
1.) Raw calibration data acquisition
2.) ZCORR_OUT calculation for the main channel data and the ZCORR_T calculation for temperature data
3.) Calibration coefficients calculation using calculated corrected raw data
Important: Results of the ADC conversion ZCORR_OUT greater than +32767 counts (15 bits) will result in negative
read-out values and a wrong analog output voltage for AOUT. In this case, a greater offset POFFS, adjusted ADC
Range Shift, or lower gain should be used.
Table 2.1
Valid Data Ranges for 15-bit and 16-bit ADC Resolution
ADC
Resolution
Range Shift
Data
Min
Max
Min
Max
Min
Max
Min
Max
16 bits
ZCORR_IN
(D8HEX & D9HEX commands)
-32768
32767
-16384
49151
-8192
57343
-4096
61439
-16384
16383
-8192
24575
-4096
28671
-2048
30719
-32768
32767
-16384
32767
-8192
32767
-4096
32767
-16384
16383
-8192
24575
-4096
28671
-2048
30719
15 bits
16 bits
15 bits
ZCORR_OUT
1/2
3/4
7/8
15/16
Recommendation: To avoid possible ADC saturation, perform a check on the ADC raw data (D0HEX and D1HEX
res
commands). For results close to the limits [0-2 ), a lower gain or adjusted RangeShift should be used.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
2.3.
Signal Conditioning Formula
The digital raw value ZCORR for the measured value to be conditioned is further processed with the correction
rd
formula to remove offset and temperature dependency and to compensate non-linearity up to 3 order. The signal
conditioning equation is computed by the CMC and is defined as follows:
 Range definition of inputs

Z CORR   2rADC ; 2rADC

Z CORR_T   2
rADC 1
;2

rADC 1

 Conditioning equations (P = Bridge Sensor Measurand)
Y
2
ZCORR  c0  2( rADC 1)  c 4  ZCORR_T  2 2( rADC 1)  c5  ZCORR_T
2
c1  2 ( rADC 1)  c6  ZCORR_T  2 2( rADC 1)  c7  ZCORR_T
Y  0; 1


P  Y 1  215  c2  215  c3  230  c2  Y 2  245  c3  Y 3
P  0; 1
rADC
Resolution of AD conversion
(13 or 14 bit)
ZCORR
Raw A/D result for measured bridge
sensor value (auto-zero compensated)
ZCORR_T Raw A/D result for temperature
(auto-zero compensated)
Conditioning coefficients stored in EEPROM
registers 0 to 7
ci  [-2 ; 2 ), two’s complement
15
15
c0 …
Bridge offset
c1 …
Gain
c2 …
Non-linearity 2
nd
order
rd
c3 …
Non-linearity 3 order
c4 …
Temperature coefficient
st
offset 1 order
c5 …
Temperature coefficient
nd
offset 2 order
c6 …
Temperature coefficient
st
gain 1 order
c7 …
Temperature coefficient
nd
gain 2 order
The first equation calculates the intermediate result Y for compensating the offset and fitting the gain including its
temperature dependence. The non-linearity is corrected in the next equation, which calculates the non-negative
value P for the measured bridge sensor value in the range [0;1). This value P is continuously written to the output
register of the digital serial interface during the measurement cycle.
Note:
The conditioning coefficients ci are positive or negative values in two’s complement format.
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© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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ZSC31150
Fast Automotive Sensor Signal Conditioner
2.4.
Analog and Digital Output
The DAC used for generation of the analog output has 5632 levels.
Important: To fit the normalized conditioning result P [0;1) to the DAC ranges, the targets for calibration must be
multiplied by 0.6875 =  5632 13  .
2 

If using the calibration library RBIC1.DLL: Note that this multiplication is done in the ZSC31150 Evaluation Kit
Software and is not contained in RBIC1.DLL. Refer to the Calibration DLL Description (RBIC_DLL_description.txt)
for a description of stand-alone usage of the DLL. RBIC1.DLL and RBIC_DLL_description.txt can be found in the
in the program folder on the user’s PC after installation of the ZSC31150 Evaluation Software.
The digital output, i.e., the conditioning result readable via the SIF, is calculated with 15-bit resolution/accuracy
(maximum). The MSB is used as the error identifier – if the MSB is set, an error is indicated. In normal cases, this
means that if the targets are adjusted for using analog output, the digital output is weighted with factor 0.6875.
If only digital output is used, targets can be calculated using the full 15-bit resolution/accuracy range. The
ZSC31150 Evaluation Kit Software offers the option for doing this.
2.5.
Digital Filter Function
The ZSC31150 offers a digital (averaging) filter function for calculating the output result in NOM. These filters can
also be used for acquiring data in calibration procedures using the START_AD_CNT command “62.”
The filter can be parameterized using two programmable coefficients stored in EEPROM: an integrating
coefficient PAVG and a differential coefficient PDIFF. (See Table 5.1.) The output Pouti is set to Pi for the first
calculation of an output result for a (new) sent command (e.g., starting NOM or “62”).
Set PDIFF and PAVG to 0 to disable the filter function. Default settings for the ZSC31150 disable the filter
function. With this function it is possible to build up a low-pass filter.
Important: Ensure that the coefficient
PDIFF  1
2 PAVG
never exceeds 1.
If this coefficient exceeds 1, the filter function can oscillate and the system gets a flywheel effect. The filter function can be described as follows:
 Digital filter function
 PDIFF  1 
Pouti  Pouti 1  Pi  Pouti 1 
 : i>0
PAVG
 2

with PAVG, PDIFF  [0; 7]
Pi
Conditioning equation result for bridge sensor signal
(refer to section 2.2)
Pouti
Output result to be calculated
PAVG Averaging filter coefficient
(EEPROM register 08HEX, [2:0])
PDIFF Differential filter coefficient
(EEPROM register 09HEX, [2:0])
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Description
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
2.6.
Output Signal Range and Limitation
The bridge sensor measurand conditioning result P for the measured value is output at the analog output pin and
SIF with >12-bit resolution. The DAC used for generation of the analog output has 5632 levels, where 5120 levels
(from 256 to 5375) can be addressed or voltage output from 4.55% to 95.44% of the supply voltage.
VOUT_MIN  VVDDE  VVSSE 
VOUT_MAX  VVDDE  VVSSE 
256
5632
5375
5632
As a result, an adjustable range from 5% to 95% of the supply including all possible tolerances is guaranteed.
Setting the analog output outside the allowed range (for example via the Set_DAC command) will result in
entering the diagnostic mode (DM) and setting the output to LDR (Lower Diagnostic Range).
Note that the limit setting registers 08HEX and 09HEX (see Table 5.1) are shared with the digital filter configuration
(the 3 LSBs).
Figure 2.1 Accessible Output Signal Range and Limitation
Addressable
Range
P out
5631
5375
Lmax
L min
256
0
Bridge Sensor Signal
BRmin
BRmax
ZSC31150 offers an output limitation function for the analog output AOUT, which clips the output signal if the
calculated result is outside of the defined limits. These output minimum and maximum limits (13-bit accuracy) are
defined in EEPROM.
 Limitation
Pout P  Lmax   Lmax
Pout P  Lmin   Lmin
Limits stored in bits [15:3] of EEPROM registers 08HEX and 09HEX:
Pout  Lmin ; Lmax 
Lmin
Lower output limit,
Lmax
Upper output limit
Lmin/max  [100HEX; 14FFHEX] or [256DEC; 5375DEC]
The output signal VOUT is ratiometric to the power supply (VVDDE - VVSSE) and can be calculated via this equation:
VOUT  VVDDE  VVSSE 
POUT
5632
POUT
Calculated digital output value for bridge sensor
VOUT
Output voltage
VVDDE, VVSSE
Potential at pins VDDE and VSSE
The digital output signal, which is calculated with 14-bit resolution, can be read out using digital serial interface
communication. Refer to section 4.3 for a detailed description of the SIF output registers.
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Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
3
Serial Digital Interface (SIF)
3.1.
General Description
The ZSC31150 includes a serial digital interface (SIF), which is able to communicate using two communication
2
protocols: I C™ and ZACwire™ one-wire communication (OWI). The SIF allows programming the EEPROM to
configure the application mode of the ZSC31150 and to calibrate the conditioning equations. It provides the read
out of the conditioning result of the measured value as a digital value. The ZSC31150 always works as a slave.
The communication protocol used is selectable. In Command Mode (CM) both communication protocols are
always available. The access mode for OWI communication is programmable in EEPROM (ADJREF: IFOWIM;
see Table 5.5). There are two start window modes and a mode with continuous OWI access. OWI access can
2
also be locked so that communication is only possible via the I C™ protocol.
An unconfigured ZSC31150, identified by a non-consistent EEPROM signature, always starts in diagnostic mode
(DM). The output is driven LOW in this case so that the lower diagnostic range can be detected. Independent
2
from the configuration, OWI and I C™ communication is enabled, any error codes can be read out, and access to
the EEPROM content for rewriting is possible.
A command consists of an address byte and a command byte. Some commands (e.g., writing data into
EEPROM) also include two data bytes. This is independent of the communication protocol used. Refer to
section 1.3 for details about working modes and section 4 for command descriptions.
There are two general types of requests to read data via the SIF from the ZSC31150:


Continuously reading the conditioning result in NOM
 Digital data read out
Reading of internal data (e.g., RAM/EEPROM content) or acquired measurement data in CM
 Calibration and/or configuration tasks
To read internal and/or measurement data from the ZSC31150 in CM, normally a specific command must be sent
to transfer this data into the output register of the SIF. Thereafter the READ command consisting of the address
byte with the read bit set is used to retrieve this data. The data transmission is continuously repeated until the
master sends a stop condition. Again this is independent of the communication protocol used. During the
measurement cycle (NOM), the ZSC31150 transfers the conditioning result into the output register of the SIF.
These data will be sent if the master generates a read-request. The active measurement cycle is not interrupted
by this.
3.1.1. Addressing
2
Addressing is supported by the I C™ and ZACwire™ interface. Every slave connected to the master responds to
a specific address. After generating the start condition, the master sends the address byte containing a 7-bit
address followed by a data direction bit (R/W). A ‘0’ indicates a transmission from master to slave (WRITE); a ‘1’
indicates a data request (READ).
The general ZSC31150 slave address is 78HEX (7-bit). The addressed slave answers with an acknowledge (only
2
I C™). All other slaves connected to the master ignore this communication. Via EEPROM programming, it is
possible to allocate and activate an additional available slave address within the range 70HEX to 7FHEX to a single
device. In this case, the device recognizes communication on both addresses, on the general one and on the
additional one.
Functional
Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
3.1.2. Communication Verification
A read request is answered by the data present in the SIF output registers (2 bytes). A cyclic redundancy check
(CRC) is also sent (1 byte) followed by the command that is being answered. The CRC and the returned
command allow the verification of received data by the master. For details and exceptions, also see section 4.3.
3.1.3. Communication Protocol Selection
2
Both available protocols, I C™ and OWI, are active in parallel, but only one interface can be used at a time.
OWI communication access is also possible if OWI communication is enabled and the analog output is active
(OWIANA and OWIWIN after start window; see section 3.3). For this option, the active output AOUT must be
overwritten by the communication master, so it is recommended that a stop condition be generated before starting
the communication to guarantee a defined start of communication (refer to section 3.3).
I2C™ Protocol
3.2.
2
For I C™ communication, a data line (SDA) and a clock line (SCL) are required.
2
Figure 3.1 I C™ – Principles of Protocol
SCL
SDA
start
condition
valid data
proper
change
of data
stop
condition
2
The I C™ communication and protocol used is defined as follows:

Idle Period
During inactivity of the bus, SDA and SCL are pulled-up to the supply voltage VDDA.

Start Condition
A high-to-low transition on SDA while SCL is at the high level indicates a start condition. Every command must be
initiated by a start condition sent by a master. A master can always generate a start condition.

Stop Condition
A low-to-high transition on SDA while SCL is at the high level indicates a stop condition. A command must be closed by
a stop condition to start processing the command routine in the ZSC31150.

Valid Data
Data is transmitted in bytes (8 bits) starting with the most significant bit (MSB). Each byte transmitted is followed by an
acknowledge bit. Transmitted bits are valid if after a start condition, SDA remains at a constant level during the high
period of SCL. The SDA level must change only when the clock signal at SCL is low.
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Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner

Acknowledge
An acknowledge after a transmitted byte is obligatory. The master must generate an acknowledge-related clock pulse.
The receiver (slave or master) pulls-down the SDA line during the acknowledge clock pulse. If no acknowledge is
generated by the receiver, a transmitting slave will become inactive. A transmitting master can abort the transmission
by generating a stop condition and can repeat the command.
A receiving master must signal the end of the transfer to the transmitting slave by not generating an acknowledgerelated clock pulse at SCL.
The ZSC31150 as a slave changes to inactive interface mode during processing internal command routines started by
a previously sent command.

Write Operation
An I²C™ WRITE operation is initiated by the master sending the slave an address byte including a data direction bit set
to ‘0’ (WRITE). The address byte is followed by a command byte and depending on the transmitted command, an
additional two data bytes (optional). The ZSC31150 internal microcontroller evaluates the received command and
processes the related routine. The following figure illustrates a write command with two data bytes and without data
bytes. A detailed description of the command set is given in section 4.1.
Figure 3.2 I²C™ – Write Operation
I2C™ Write, Command Byte, and 2 Data Bytes
S 6 5 4 3 2 1 0 W A 7 6 5 4 3 2 1 0 A 15 14 13 12 11 10 9 8 A 7 6 5 4 3 2 1 0 A S
Device Slave
Address [6:0]
Wait for
Slave ACK
Command
Byte [7:0]
Wait for
Slave ACK
Data
Wait for
Byte [15:8] Slave ACK
Data
Byte [7:0]
Wait for
Slave ACK
I2C™ Write, Command Byte, No Data Bytes
S 6 5 4 3 2 1 0 W A 7 6 5 4 3 2 1 0 A S
Device Slave
Address [6:0]
Wait for
Slave ACK
S Start Condition
5
Device Slave Address
(example: Bit 5)
Functional
Description
June 30, 2014
Command
Byte [7:0]
Wait for
Slave ACK
S Stop Condition
W
Read/Write Bit
(example: Write=0)
4
Command Bit
(example: Bit 4)
2
Data Bit
(example: Bit 2)
A Acknowledge (ACK)
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner

Read Operation
After a data request from master to slave by sending an address byte including a data direction bit set to ‘1’
(READ), the slave answers by sending data from the interface output registers. The master must generate
the transmission clock on SCL, the acknowledges after each data byte (except after the last one), and the
stop condition at the end.
A data request is answered by the ZSC31150’s interface module and consequently does not interrupt the
current process of the internal microcontroller.
Note: The data in the activated registers is sent continuously until a stop condition is detected; after
transmitting all available data, the slave starts repeating the data.
Figure 3.3 I²C™ – Read Operation – Data Request
Optional
I2C™ Read, 2 (+n) Data Bytes
S 6 5 4 3 2 1 0 R A 15 14 13 12 11 10 9 8 A 7 6 5 4 3 2 1 0 A 7 6 5 4 3 2 1 0 N S
Device Slave
Address [6:0]
Wait for
Slave ACK
S Start Condition
5
Device Slave Address
(example: Bit 5)
Data Byte
[15:8]
Master
ACK
S Stop Condition
R
Read/Write Bit
(example: Read=1)
Data Byte
[7:0]
Master
ACK
...nth Data Byte
A Acknowledge (ACK)
2
N
Master
NACK
No Acknowledge
(NACK)
Data Bit
(example: Bit 2)
During an active measurement cycle, data is constantly updated with conditioning results. To get other data from
the slave (e.g., EEPROM content) typically a specific command must be sent before the data request to initiate
the transfer of this data to the interface output registers. This command does interrupt the current process of the
internal microprocessor and consequently also interrupts an active measurement cycle.
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Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Figure 3.4 I²C™ – Timing Protocol
tI2C_R
tI2C_F
SCL
tI2C_SU_STA
tI2C_HD_STA
tI2C_SU_DAT
tI2C_HD_DAT
SDA
tI2C_H
tI2C_L
SCL
tI2C_SU_STO
tI2C_HD_STA
SDA
tI2C_BF
Table 3.1
2
Timing I C™ Protocol
Nr.
Parameter
Symbol
Conditions
Min
Typ
fOSC ≥ 2MHz
Max
Unit
400
kHz
1
SCL clock frequency
fSCL
2
Bus free time between start and stop condition
tI2C_BF
1.3
s
3
Hold time start condition
tI2C_HD_STA
0.6
s
4
Setup time repeated start condition
tI2C_SU_STA
0.6
s
5
Low period SCL/SDA
tI2C_L
1.3
s
6
High period SCL/SDA
tI2C_H
0.6
s
7
Data hold time
tI2C_HD_DAT
0
s
8
Data setup time
tI2C_SU_DAT
0.1
s
9
Rise time SCL/SDA
tI2C_R
0.3
s
10
Fall time SCL/SDA
tI2C_F
0.3
s
11
Setup time stop condition
tI2C_SU_STO
12
Noise interception SDA/SCL
tI2C_NI
s
0.6
Spike suppression
50
ns
2
Note: See section 1.4 of the ZSC31150 for additional specifications related to the I C™ interface.
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Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
3.3.
Digital One-Wire Interface (OWI)
TM
The ZSC31150 employs ZMDI’s ZACwire , a one-wire digital interface concept (OWI). It combines a simple and
easy protocol adaptation with a cost-saving pin sharing. The communication principle of the OWI interface is
2
2
derived from the I C™ protocol. Becoming familiar with the I C™ protocol is recommended for an understanding
of OWI communication.
Both the analog voltage output and the digital interface (calibration and/or digital output value) use the same pin,
AOUT. An advantage of OWI output signal capability is that it enables “end of line” calibration – no additional pins
are required to digitally calibrate a finished assembly. However, although the OWI was designed mainly for
calibration, it can also be used to digitally read out the calibrated sensor signal continuously.
These two communication tasks are supported by different configurations of the interface. Depending on the
EEPROM configuration (ADJREF:IFOWIM, see Table 5.5), there are 4 different modes for OWI:

OWIENA  OWI enabled
OWI remains active at the AOUT pin; analog output is disabled.
(Note: no internal pull-up resistor is implemented.)

OWIWIN  OWI startup window
OWI is enabled during the startup window (~100ms minimum) and is disabled if the startup window times out without
receiving a valid START_CM command [72D1HEX]. Analog voltage output is activated after the startup window elapses.
(Note: no internal pull-up resistor is implemented).

OWIANA  OWI startup window with Analog Out
Analog voltage output is activated after startup time (maximum 5ms). OWI is enabled during the startup window
(~100ms minimum) and is disabled if the startup window times out without receiving a valid START_CM command
[72D1HEX]. When sending the START_CM command, the master must overwrite the active analog voltage output
(IOUT max = 20mA).

OWIDIS  OWI disabled
2
OWI communication is not possible. Access to the ZSC31150 is only available via the I C™ interface.
Figure 3.5 Block Diagram of the OWI Connection
Note: An external pull-up must be provided; no guarantee for usage of the ZSC31150 internal pull-up.
ZSC31150
R OWI_PUP
C OWI_LINE
R OWI_LINE
In Command Mode (CM), communication via OWI is possible if OWI is enabled. Typically the ZSC31150 is in the
OWIENA mode. After specific commands requesting an analog output at the AOUT pin, the mode is comparable
to OWIANA but without a timeout.
Both devices are peers; however only the external device starts communication and requests data. In this sense,
it is referred to as the master and the ZSC31150 as slave.
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Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
In the case of an invalid EEPROM signature, the lower diagnostic range (LDR) driven at the analog output AOUT
pin must be overwritten (IOUT max=20mA) for sending the START_CM command. A push-pull driver is necessary
for this. It is possible to overwrite the driven analog output AOUT by a communication sequence if OWI is enabled
(refer to the OWI modes described above).
Properties and Parameters
Although the OWI is designed as a bilateral connection, for reasons of compatibility, the protocol used is
2
equivalent to I C™ communication. This means a command always includes an address byte with a read/write bit.
OWI communication is self-locking (synchronizing) on the master’s communication speed within the range
specified for OWI bit time, which is guaranteed for ZSC31150’s clock frequency in the range of 2 to 4 MHz.
The OWI communication start window in OWIANA and OWIWIN mode is 52700 internal frequency clocks long
(~100ms minimum). To initiate OWI communication and enter the Command Mode, the START_CM command
must be sent during this period.
Table 3.2
Nr.
OWI Interface Parameters
Parameter
Symbol
Conditions
Min
Max
Unit
0.04
4
ms
0.3
3.30
k
20
33

1
OWI bit time
1)
tOWI_BIT
2
Pull-up resistance – master
ROWI_PUP
3
OWI line resistance
ROWI_LINE
ROWI_LINE < ROWI_PUP/100
4
OWI load capacitance
COWI_LOAD
Total OWI line load
50
nF
5
Voltage level low
VOWI_IN_L
Minimum VDDA is 4.2V @ 4.5V VDDE
0.2
VDDA
6
Voltage level high
VOWI_IN_H
Maximum VDDA is 5.5V @ 5.5V VDDE
tBIT = 5  ROWI_PUP  COWI_LOAD
0.75
VDDA
1) Range is guaranteed independent of the clock frequency adjustment. Also see Table 3.3 for more details.
The OWI communication and protocol used is defined as follows:

Idle Period
During inactivity of the bus, the OWI communication line is pulled-up to the supply voltage VDDA.

Start Condition
When the OWI communication line is in idle mode, a low pulse (return to one) with a minimum tOWI_STA width of 25s
indicates a start condition. Every command must be initiated by a start condition sent by a master. A master can
generate a start condition only when the OWI line is in the idle mode.

Stop Condition
The master finishes a transmission by changing back to the high level (idle mode). Every command (see the following
“Write Operation” section for details) must be closed by a stop condition in order to start processing the command. The
master can interrupt a transmitting slave after a data request (refer to “Read Operation” below) by clamping the OWI
line to the low level for generating a stop condition.
A stop condition is indicated by no transition from low to high or from high to low (constant level) at the OWI line for at
least twice the period of the last transmitted valid bit or more than the doubled bit time. A stop condition without regard
to the last bit-time (secure stop condition) is generated by a constant level at the OWI line for more than 32766 clocks
of the internal clock oscillator. A secure stop condition is also generated at bit times less than 80 clocks of the clock
oscillator.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
In the case of overwriting an active AOUT (e.g., upon starting communication in OWIANA mode), a stop condition must
be generated independently from the current AOUT potential, which can be LOW or HIGH. The timing patterns shown
in Figure 3.6 ensure proper generation of the stop condition:
Figure 3.6 OWI – Stop Condition for Active Driven AOUT
AOUT
one bit time
= 100µs

one bit time
= 100µs
one bit time
= 100µs
stop condition = 300µs
(longer than two bit times)
1st bit of data
(LOW or HIGH)
start cond.
= 100µs
2nd bit
Valid Data
Data is transmitted in bytes (8 bits) starting with the most significant bit (MSB). Transmitted bits are recognized after a
start condition at every transition from low to high on the OWI line. The value of the transmitted bit depends on the duty
ratio between the high phase and high/low period (bit period, t OWI_BIT; see Table 3.3). A duty ratio greater than 1/8 and
less than 3/8 is detected as a 0; a duty ratio greater than 5/8 and less than 7/8 is detected as a 1.
The bit period of consecutive bits must not change by more than a factor of 2 because a stop condition is detected in
this case.

Write Operation
An OWI WRITE operation is initiated by the master sending the slave an address byte including a data direction bit set
to 0 (WRITE). The address byte is followed by a command byte and depending on the transmitted command, an
additional two data bytes (optional). The ZSC31150 internal microcontroller evaluates the command received and
processes the related routine. Figure 3.7 illustrates the write of a command with two data bytes and without data bytes.
A detailed description of the command set is given in section 4.1.
Figure 3.7 OWI – Write Operation
OWI Write: Master Sends Address, Command, and 2 Data Bytes
Optional
S 6 5 4 3 2 1 0 W 7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 S
Device Slave
Address [6:0]
Command
Byte [7:0]
Data
Byte [15:8]
Data
Byte [7:0]
OWI Write: Master Sends Address and Command Bytes, No Data
S Start Condition
S Stop Condition
S 6 5 4 3 2 1 0 W 7 6 5 4 3 2 1 0 S
Device Slave
Address [6:0]
Functional
Description
June 30, 2014
5
Device Slave Address
(example: Bit 5)
W
Read/Write Bit
(example: Write=0)
4
Command Bit
(example: Bit 4)
2
Data Bit
(example: Bit 2)
Command
Byte [7:0]
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ZSC31150
Fast Automotive Sensor Signal Conditioner

Read Operation
After a data request from the master to a slave by sending an address byte including a data direction bit set to 1
(READ), the slave answers by sending data from the interface output registers. The slave generates the data bits with a
bit period equal to the last received bit (R/W bit). The master must generate a stop condition after receiving the
requested data.
A data request is answered by the ZSC31150’s interface module, so it does not interrupt the current process of the
internal microcontroller.
The data in the output registers is sent continuously until a stop condition is detected; after transmitting all available
data, the slave starts repeating the data.
During the active measurement cycle, data is constantly updated with conditioning results. To get other data from the
slave (e.g., EEPROM content) normally a specific command must be sent before the data request to initiate the transfer
of this data to the interface output registers. This command does interrupt the present operation of the internal
microcontroller and consequently also interrupts any active measurement cycle.
Figure 3.8 OWI – Read Operation – Data Request
OWI Read: 2 + n Data Bytes
Data are automatically sent in a loop by slave until master sends stop condition
Optional
S 6 5 4 3 2 1 0 R 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0 S
Device Slave
Address [6:0]
Sent by
Data
Byte [15:8]
Master
S Start Condition
...nth Data
Byte [7:0]
Data
Byte [7:0]
Slave
S Stop Condition
5
Device Slave Address
(example: Bit 5)
Master
R
Read/Write Bit
(example: Read=1)
2
Data Bit
(example: Bit 2)
nth data byte = last requested data byte
Figure 3.9 OWI – Timing Protocol
Start
1
0
0
1
Stop
Start
Write Mode
Read Mode
tOWI_STA
Functional
Description
June 30, 2014
tOWI_BIT
tOWI_0
tOWI_1
tOWI_STO
tOWI_IDLE
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 3.3
Nr.
OWI Timing Protocol
Parameter
1
Bus free time
2
Hold time start condition
2)
1)
Symbol
Conditions
tOWI_IDLE
Between start and stop
tOWI_STA
s
Duty ratio bit ‘0’
tOWI_0
0.125
5
Duty ratio bit ‘1’
tOWI_1
0.625
6
Hold time stop condition
Bit period deviation
tOWI_BIT_DEV
Unit
25
4
7
Max
s
Bit period range
tOWI_STO
fOSC = 4MHz (min.); 2MHz (max.)
Typ
25
3
1)
2)
tOWI_BIT
Min
8000
s
0.25
0.375
tOWI_BIT
0.75
0.875
tOWI_BIT
20
Minimum tOWI_BIT (20ms) to bit
period of last valid bit
(Also see “Stop Condition” on
page 20 for further details.)
2.0
Current bit to next bit
0.55
tOWI_BIT_L
1.0
1.5
tOWI_BIT
This hold time is valid for all frequency adjustments for the ZSC31150.
This bit period range is achievable with different frequency adjustments. OWI communication is always possible in the OWI bit time specified in Table 3.2.
4
Interface Commands
4.1.
Command Set
2
All commands are only available in Command Mode (CM) (see section 1.3.2) and for I C™ and OWI
communication. CM is initiated by sending the START_CM command [72D1HEX]. See Table 4.1 for command
descriptions and processing time.
In CM, every command received is answered. The response consists of the two bytes of requested data or validation code, 1 byte for the CRC, and the 1-byte command reply. For more details about responses, see sections 4.3
and 4.4.
Important: Before sending commands that write to EEPROM registers, EEPROM programming must be enabled
by sending the EEP_WRITE_EN command 6CF742HEX.
A read command can be sent during an active measurement cycle (i.e., the processing time has not yet elapsed
after sending one of the STRT_CYC_x or START_AD_x commands indicated by gray shading in Table 4.1). For
example, the SIF can be read during the START_AD_CNT command. If any of the other commands is to be sent
during an active measurement cycle, the measurement command must first be aborted. Typically an active
measurement cycle is aborted if a non-read command is received, but in special cases, the command might not
be received correctly and the active measurement is not aborted. Therefore, for safe communication during an
active measurement cycle, ZMDI recommends sending the START_CM command [72D1HEX] first for non-read
commands.
Functional
Description
June 30, 2014
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 4.1
Command
(HEX)
Command Set
Data
Command
Notes
Processing
Time
@ fCLK=3MHz
01 / 02
STRT_CYC_EEPOWI /
STRT_CYC_RAMOWI
Start measurement cycle including initialization from EEPROM/RAM for
digital output with activation of OWI mode OWIENA.
350s / 220s
03 / 04
STRT_CYC_EEPANA /
STRT_CYC_RAMANA
Start measurement cycle including initialization from EEPROM/RAM for
analog output with activation of OWI mode OWIANA.
350s / 220s
05 / 06
STRT_CYC_EEPOWIDIS / Start measurement cycle including initialization from EEPROM/RAM for
STRT_CYC_RAMOWIDIS digital output with OWI mode disabled (OWIDIS mode).
350s / 220s
07 / 08
STRT_CYC_EEP /
STRT_CYC_RAM *
Start measurement cycle including initialization from EEPROM/RAM.
350s / 220s
10 to 1E
READ_RAM
Read data from RAM address 00HEX to 0EHEX.
50s
30 to 43
READ_EEP
Read data from EEPROM address 00HEX to 13HEX.
50s
ADJ_OSC_ACQ
Acquire frequency ratio of internal oscillator to communication
frequency (fOSC / fOWI) for adjusting internal oscillator frequency by
ADJREF:OSCADJ.
Important: Use this command only with OWI communication.
50s
Set analog output (DAC) to value defined by data bytes.
40s
50
60
2 Bytes SET_DAC
Note for OWIWIN and OWIANA: OWI communication is disabled
after the startup window).
Important note: If the data byte is outside the allowed range of 0100HEX
to 14FFHEX, the ZSC31150 will enter DM and output the LDR (lower
diagnostic range). The AOUT pin goes into tri-state during processing.
62
2 Bytes START_AD_CNT
Process an A/D conversion <n>(= data) times for input voltage and
temperature, auto-zero corrected.
Result is updated continuously in digital output registers
(4 data bytes), last values remain after processing.
<2n>
(D8+D9)
commands
See 4.5.1 for details.
65
2 Bytes ADJ_OSC_WRI
Write and activate oscillator adjust value to RAM ADJREF:OSCADJ,
returns compete configuration word ADJREF.
50s
Important: Use this command only with OWI communication
*
6C
2 Bytes EEP_WRITE_EN
Enable data write to EEPROM when sent with data F742HEX;
sending any other data disables EEPROM writing.
50s
72
1 Byte
Start Command Mode (CM); always send with data D1HEX.
50s
50s
START_CM
80 to 8E
2 Bytes WRITE_RAM
Write data to RAM addresses 00HEX to 0EHEX respectively.
A0 to B2
2 Bytes WRITE_EEP
Write data to EEPROM addresses 00HEX to 12HEX respectively.
12.5ms
C0
COPY_EEP2RAM
Copy the content of EEPROM addresses 00HEX to 0EHEX to RAM;
restores EEPROM configuration in RAM.
130s
C3
COPY_RAM2EEP
Copy the content of RAM addresses 00HEX to 0EHEX to EEPROM;
generates the EEPROM signature and writes it to address 0FHEX,
returns the EEPROM signature.
200ms
Note: For product versions ZSC31150Exx and earlier, the commands STRT_CYC_EEP and STRT_CYC_RAM are not available.
Functional
Description
June 30, 2014
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Command
(HEX)
Data
Command
Processing
Time
@ fCLK=3MHz
Notes
C8
GET_EEP_SIGN
Calculates EEPROM signature and writes the result to SIF output
register 1 (SIF1; see Table 4.2).
150s
C9
GEN_EEP_SIGN
Calculates EEPROM signature and writes it to EEPROM address
0FHEX and writes the result to SIF1.
12.6ms
CA
GET_RAM_SIGN
Calculates RAM signature and writes the result to SIF1.
150s
CF
ROM_VERSION
Get hardware and ROM version:
 ROM version is defined by the low byte “CF” command answer.
 Design version is defined by the high byte “CF” command answer.
ZSC31150Axx = 0AxxHEX
ZSC31150Exx = 0ExxHEX
ZSC31150Cxx = 0CxxHEX
ZSC31150Fxx = 0FxxHEX
ZSC31150Dxx = 0DxxHEX
ZSC31150Gxx = 19xxHEX
50s
Note: All Dx commands are used for the calibration process, write raw conversion result to SIF output registers, and do not generate analog
output. Conversion time with fCLK=3MHz for all “D” commands is 50s + A/D conversion time.
Command (HEX)
Command
Notes
D0
START_AD_BR
Start cyclic A/D conversion at bridge sensor channel (BR); e.g., pressure measurement.
D1
START_AD_T
Start cyclic A/D conversion at temperature channel (T).
D2
START_AD_SSCP
Start cyclic A/D conversion for positive-biased Sensor Short Check and Sensor Connection
Check.
D3
START_AD_CMV
Start cyclic A/D conversion for common mode voltage measurement for Sensor Aging Check.
D4
START_AD_BR_AZ
Start cyclic A/D conversion auto-zero (AZ) at bridge sensor channel (BR); e.g., pressure
D5
START_AD_TAZ
Start cyclic A/D conversion auto-zero at temperature channel (TAZ).
D6
START_AD_SSCN
Start cyclic A/D conversion for negative-biased Sensor Short Check and Sensor Connection
Check.
D8
START_AD_BR_AZC
Start cyclic A/D conversion at bridge sensor channel (BR) including auto-zero.
D9
START_AD_T_AZC
Start cyclic A/D conversion at temperature channel (T) including auto-zero.
DA
START_AD_SSCPSSCN
Start cyclic A/D conversion for positive and negative biased Sensor Short Check and Sensor
Connection Check.
DB
START_AD_CMV_AZC
Start cyclic A/D conversion for common mode voltage measurement (for Sensor Aging
Check) including auto-zero.
Functional
Description
June 30, 2014
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
4.2.
Command Processing
2
All commands are available for both I C™ and OWI protocols (except ADJ_OSC_ACQ and ADJ_OSC_WRI). If
CM is active, reception of a valid command interrupts the internal microcontroller (CMC) and starts a routine
processing the received command. The processing time depends on the internal system clock frequency
(minimum: ~2MHz; adjustable by EEPROM programming). For a data read from the ZSC31150, the requested
data (e.g., register content or acquired measurements) is written to the SIF output register and can be read out by
a read request.
4.3.
SIF Output Registers
The serial interface (SIF) contains two 16-bit output registers that can be read out by a read request. Depending
on the configuration of ADJREF:IFOWIM, access to the one-wire interface (OWI) can be limited during NOM.
Depending on the present operation mode of ZSC31150 (NOM, CM or DM; refer to section 1.3), different data are
written to SIF output registers. The output registers SIF1 and SIF2 are continuously updated.
Note: If the update rate is high, a CRC error might occur if data is read out in NOM during an active measurement
cycle (e.g., the START_AD_CNT command). Refer to the ZSC31150 Data Sheet and the ZSC31150 Bandwidth
Calculation Spreadsheet for more details about the update rate. The data readout occurs word-by-word.
Therefore it is possible that during reading the first word (SIF1), the output register is updated with a new
conditioned value and thus the CRC is also updated. The CRC value for the new conditioned value is read out
within the next word (SIF2). The new conditioned value could have a different CRC value than was read out as
the first word and so an apparent CRC error is detected.
Recommendation: To prevent such misinterpretation in these cases, read at least 6 bytes as shown in Figure
4.1. If an invalid CRC is detected in the first four bytes, the second SIF1 reading can be used to check whether a
misinterpretation of the CRC has occurred or a CRC error occurred.
Figure 4.1 Preventing Misinterpretation of CRC
Measurement Cycle
Next Measurement Cycle Executed by Microcontroller (CMC)
End of measurement cycle causes an update at the SIF registers
Start of
readout
from
master
Functional
Description
June 30, 2014
SIF1
Conditioned Value
High Byte
Low Byte
SIF2
SIF1
CRC
00HEX
High Byte
Low Byte
Conditioned Value
High Byte
Low Byte
SIF2
CRC
00HEX
High Byte
Low Byte
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
...
26 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 4.2
Output Register Contents of Serial Digital Interface (SIF) When Processing Commands
Output Register 1 (SIF1)
Mode/ Commands
High Byte
Low Byte
Output Register 2 (SIF2)
High Byte
Low Byte
Normal Operation Mode (NOM)
CRC
00HEX
Requested RAM or EEP data
Read RAM or EEP (Commands
10HEX to 1EHEX and 30HEX to 43HEX).
CRC
Processed command
START_AD_xx (DxHEX commands)
CRC
Processed command *
Conditioned value:
<error flag(MSB)> <15-bit data>
Command Mode (CM)
Measured raw value
START_AD_CNT (Command 62HEX) Measured raw value (e.g., pressure)
Measured raw value temperature
STRT_CYC_xx (01HEX to 08HEX)
Conditioned value => refer to NOM
Commands without output
Success code C3xxHEX; see Table 4.3
CRC
Processed command
SET_DAC (Command 60HEX)
DAC adjustment data
CRC
60HEX
ADJ_OSC_ACQ (Command 50HEX)
Oscillator adjustment count
CRC
50HEX
ADJ_OSC_WRI (Command 65HEX)
The new configuration word ADJREF
CRC
65HEX
Error code C0xxHEX; MSB = error flag = 1
CRC
00HEX
Diagnostic Mode (DM)
The CRC is calculated using following formula: CRC = FFHEX – (high byte + low byte).
4.4.
Command Response Codes
In CM, every command received is answered with either data or a success/failure code. Table 4.3 gives the codes
for the first word of the response to commands. The high byte of the second word contains the CRC and the low
byte repeats the processed command.
Table 4.3
Command Response: First Readout Word (SIF Output Register 1)
Command
Success Code
6C F742HEX C36CHEX
Failure Detected Code
CF6CHEX
Notes
Charge pump enable in order to write data to EEPROM
72 D1HEX
C372HEX
Start Command Mode
C0HEX
C3C0HEX
Copy EEP to RAM
C3HEX
C3C3HEX
CFC3HEX
Copy RAM to EEP
xy
-
CF00HEX
Wrong command or data missing
xy
-
C000HEX
Command processing error or undefined internal error
C0xxHEX where xx  00
C0xxHEX indicates the Diagnostic Mode; see Table 1.1 (if the DM
is “temporary,” then the measurement cycle continues)
Commands
that initiate
NOM
*
For product versions ZSC31150Dxx and earlier, the value 00HEX was sent in place of the processed command.
Functional
Description
June 30, 2014
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
4.5.
Detailed Description for Specific Commands
4.5.1. START_CM (72D1HEX)
As described in section 1.3.1, the ZSC31150 starts in NOM. In this mode, it continuously measures the input
signal and refreshes the SIF. To start the Command Mode, a START_CM command via I²C™ must be
transmitted to the ZSC31150. This command is shown in Figure 4.2.
Figure 4.2 START_CM Command
I2C™ Write for START_CM Command: Address, Command (72), and Data (D1HEX) Bytes
S 1 1 1 1 0 0 0 W A 0 1 1 1 0 0 1 0 A 1 1 0 1 0 0 0 1 A S
Device Slave
Address [6:0]
Example: 78HEX
Wait for
Slave ACK
S Start Condition
1
Device Slave Address
(Example: High)
Command
Byte [7:0]
(72HEX)
Wait for
Slave ACK
S Stop Condition
W
Read/Write Bit
(Example: Write=0)
Data
Byte [7:0]
(D1HEX)
Wait for
Slave ACK
0
Command Bit
(Example: Low)
1
Data Bit
(Example: High)
A Acknowledge (ACK)
When sending the START_CM command to abort the NOM or a raw data acquisition command (DxHEX), the
command execution can be affected by the internal asynchronous processed update of the SIF output register. In
this case, the received command could be overwritten and therefore the Command Mode would not be entered.
Checking the response to the START_CM command to ensure that CM was started is recommended. If the
ZSC31150 answers with C372HEX, entering CM was successful; otherwise, send the START_CM command
again. Depending on internal conditions, if the secondary SIF address is used for communication, it is possible
that the ZSC31150 will not answer communication requests from that point forward. If this occurs, use the primary
2
I C™ address (78HEX) for restarting the ZSC31150 with a START_CM command and then the secondary address
will be functional again.
4.5.2. START_AD_CNT (62HEX)
The START_AD_CNT command is used for synchronized bridge sensor (the measurand; e.g., pressure) and
temperature raw calibration data acquisition during the calibration process. The possible synchronization enables
a raw data acquisition (snapshot) for all attached devices under test (DUTs) under temperature drift and
measurand leakage conditions, which is especially useful for mass calibration.
Two data inputs are evaluated and required for processing of the START_AD_CNT command:

Average count (cavg) for calibration based on the PAVG bits [2:0] in register 08HEX: cavg  2

Conversion cycle count <cccnt> to be processed (recommendation: cccnt  2
Functional
Description
June 30, 2014
PAVG
PAVG
8)
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ZSC31150
Fast Automotive Sensor Signal Conditioner
All necessary A/D conversions (measurand, temperature, auto-zero) are cyclic. For the A/D conversions, the
START_AD_CNT command implements the following Dx commands in this sequence:

D5, D1 (for temperature measurand), which is equivalent to the D9 HEX command (T_AZC = T - TAZ)

D4, D0 (for bridge sensor measurand), which is equivalent to the D8 HEX command (BR_AZC = BR - BR_AZ).
The two data bytes attached to the START_AD_CNT command define the count of conversion cycles <cccnt>.
The A/D conversion is stopped after processing the required count of conversion cycles.
Table 4.4
START_AD_CNT – Data Word Description
Bit#
data <15:0>
Description
Conversion cycle count <cccnt> to be processed
During A/D conversion, the SIF output registers are continuously updated, so temporary results can be read out
during processing the command and the result is valid after processing the last conversion. The time needed for
this can be estimated by following formula:
readout_delay   AD conversion time  4.1 cccnt   1
After the command is processed, the last or averaged result is readable in the SIF output registers until the next
command. The averaged value is calculated using the filter formula (refer to section 2.5) with PDIFF = 0 and
PAVG = log2 <cavg> and Poutn-1 = Poutn.
Table 4.5
START_AD_CNT – Command Response Description
Command
SIF1
SIF2
START_AD_CNT
Bridge Sensor Measurand BR_AZC
Temperature T_AZC
4.5.3. ADJ_OSC_ACQ (50HEX) and ADJ_OSC_WRI (65xxxxHEX)
The ADJ_OSC_xxx commands are used to adjust the frequency of the internal oscillator. This frequency is
adjustable in the range of 2 to 4 MHz and has a directly proportional effect on the A/D conversion time. The
internal oscillator frequency can be adjusted by ADJREF:OSCADJ (see section 5.2). The default value 12HEX
corresponds to a frequency of 3MHz. The frequency is changed per count by a step of approximately -125kHz
(frequency is decreased if OSCADJ is increased).
TM
The ADJ_OSC_ACQ command is sent first. Note: This command works only with ZACwire communication
(OWI). It returns the ratio of the internal oscillator frequency to the communication frequency fOSC/fOWI. Since the
communication frequency fOWI is known, the current internal oscillator frequency f OSC can be calculated. Note that
the resolution of the frequency measurement improves as the communication frequency decreases.
The change in ADJREF:OSCADJ needed to reach the target frequency can be calculated from the ratio fOSC/fOWI
and the adjustment of -125kHz/step. The ADJ_OSC_WRI command is used to write the ADJREF:OSCADJ to
RAM and to activate the new adjustment. The command returns the complete configuration word ADJREF (all
other configuration bits keep their value).
Functional
Description
June 30, 2014
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ZSC31150
Fast Automotive Sensor Signal Conditioner
This sequence allows an easy and accurate adjustment of the internal frequency during end-of-line calibration.
Table 4.6
Oscillator Frequency Adjustment Sequence / Tasks (OWI Only)
Communication
Command Description
Comment
Task: Measure and adjust the internal frequency
[72 D1]
START_CM
Start command mode
[1D]
READ_RAM 0xD
Read RAM ADJREF
[SIF-READ]
READ ADJREF
Read ADJREF; OSCADJ = ADJREF[4:0]
[50]
ADJ_OSC_ACQ
Acquire frequency ratio of internal oscillator to
communication frequency
[SIF-READ]
READ F_RATIO
Read F_RATIO = fOSC/fOWI or fOSC = F_RATIO*fOWI
fOSC,new – F_RATIO*fOWI
D_OSCADJ =
-125kHz
OSCADJnew = OSCADJ + D_OSCADJ
[65 OSCADJnew]
ADJ_OSC_WRI
Write ADJREF:OSCADJ
[SIF-READ]
READ ADJREF
Read ADJREFnew
Task: Check the resulting internal frequency (optional)
[50]
ADJ_OSC_ACQ
Acquire frequency ratio of internal oscillator to
communication frequency
[SIF-READ]
READ F_RATIO
Read F_RATIO
Task: Write the new frequency adjustment to EEPROM
[6C F742]
EEP_WRITE_EN
Enable data write to EEPROM
[AD ADJREFnew]
WRITE_EEP
Write EEPROM ADJREFnew
[C9]
GEN_EEP_SIGN
Generate and write EEPROM signature
Functional
Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
5
EEPROM and RAM
5.1.
Programming the EEPROM
Programming the EEPROM is done using an internal charge pump to generate the required programming
voltage. The timing of the programming pulses is controlled internally. The programming time for a write operation
is typically 12.5ms independent of the programmed clock frequency (ADJREF:OSCADJ). Recommendation: Wait
at least 15ms per write operation before starting the next communication.
To program the EEPROM, it is necessary to set the ZSC31150 in Command Mode via the START_CM command
(72 D1HEX) and to enable EEPROM programming via the EEP_WRITE_EN command (6C F7 42HEX). Writing data
to the EEPROM is done via the serial digital interface by sending specific commands (refer to section 4). The
WRITE_EEP command includes the address of the targeted EEPROM word and is followed by two data bytes.
During EEPROM programming, the serial digital interface is disabled so that no further commands can be
recognized.
The COPY_RAM2EEP command writes the content of the RAM mirror area to the EEPROM. This is to simplify
the calibration process when the ZSC31150 is configured iteratively. The EEPROM signature, which is not
mirrored in RAM is generated, written to EEPROM, and returned to the SIF output register. This copy operation
includes 16 EEPROM write operations and therefore typically requires 200ms (recommended wait time: 250ms).
5.2.
EEPROM and RAM Content
The configuration of the ZSC31150 is stored in 20 EEPROM 16-bit words.
Calibration constants for conditioning the sensor signal by the conditioning calculation and analog output limits
are stored in 11 words. There are three words for setting the configuration of the ZSC31150 regarding the application. One register is used for storing the EEPROM signature, which is used in NOM to check the validity of the
EEPROM content after power-on. Three additional 16-bit words are for arbitrary free user data.
After every power-on, the EEPROM content is mirrored to RAM. During this readout, the content of the EEPROM
is checked by calculating the signature and comparing it with the stored one. If a signature error is detected, the
ZSC31150 starts in DM. In this case, the LDR is driven at the analog output and the OWI interface is activated.
The error code is send to the SIF output register.
The configuration of the device is done from the mirrored area in RAM. Therefore the configuration words are
transferred to the internal registers. The calibration constants for the conditioning calculation are also read from
RAM. Thus every change to the RAM mirror area impacts the configuration and functioning of the device after the
next start of cyclic measurement.
After power-on, the content of the RAM mirror area is determined by the EEPROM content and can then be
changed by specific commands writing to RAM. A new configuration can be activated by the STRT_CYC_RAMx
commands or START_AD_x commands.
Table 5.1
EEPROM and RAM Content
EEPROM/RAM
Address
Write Cmd
RAM/EEP
Default
Configuration
Description
(Note: when bits are divided, the description begins with MSB and ends with LSB)
Conditioning Coefficients – Correction formula for bridge sensor measurand (see section 2.2)
00HEX
80/A0HEX
1000HEX
c0 - Offset
01HEX
81/A1HEX
4000HEX
c1 - Gain
Functional
Description
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ZSC31150
Fast Automotive Sensor Signal Conditioner
EEPROM/RAM
Address
Write Cmd
RAM/EEP
Default
Configuration
Description
(Note: when bits are divided, the description begins with MSB and ends with LSB)
02HEX
82/A2HEX
0000HEX
c2 - Non-linearity, 2nd order
03HEX
83/A3HEX
0000HEX
c3 - Non-linearity, 3rd order
04HEX
84/A4HEX
0000HEX
c4 - Temperature coefficient offset, 1 order
05HEX
85/A5HEX
0000HEX
c5 - Temperature coefficient offset, 2
st
st
nd
order
06HEX
86/A6HEX
0000HEX
c6 - Temperature coefficient gain, 1 order
07HEX
87/A7HEX
0000HEX
c7 - Temperature coefficient gain, 2
nd
order
Conditioning Coefficients – Limit and/or filter the analog output at pin AOUT (see section 2.5 and 2.6)
08HEX
88/A8HEX
0800HEX
13 bits:
Lmin - Lower limit for analog output via pin AOUT
3 bits (LSB): PAVG - Output low-pass filter (LPF) averaging coefficient PAVG
09HEX
89/A9HEX
A7F8HEX
13 bits:
Lmax - Upper limit for analog output via pin AOUT
3 bits (LSB): PDIFF - Output LPF differential coefficient PDIFF
Common Mode Voltage Measurement (CMV) Limits
0AHEX
8A/AAHEX
FF00HEX
8 bits:
CMVmax – Upper limit common mode voltage
8 bits (LSB): CMVmin – Lower limit common mode voltage
Configuration Words (see section 5.2.2)
0BHEX
8B/ABHEX
0013HEX
CFGAFE:
Configuration of analog front-end
0CHEX
8C/ACHEX
0458HEX
CFGAPP:
Configuration of target application
0DHEX
8D/ADHEX
2112HEX
ADJREF:
Adjustment of system, communication settings, etc.
0EHEX
8E/AEHEX
0000HEX
RSVD:
Reserved
- /AFHEX
6F8CHEX
Signature
CRC
0FHEX
Application Free Memory (not included in signature)
10HEX
- /B0HEX
xxx
Free user memory, not included in signature
11HEX
- /B1HEX
xxx
Free user memory, not included in signature
12HEX
- /B2HEX
xxx
Free user memory, not included in signature
13HEX
- /B3HEX
xxx
No customer access; ZMDI restricted use
Note: The ZSC31150 is delivered with default contents in the registers. The specified default configuration can be
changed. Registers’ content must be rewritten completely during the calibration procedure. At delivery, registers
10HEX, 11HEX, and 12HEX contain traceability data (lot#, wafer#, and device#; refer to section 5.2.1 for details).
Register 13HEX contains variable ZMDI internal data at delivery. ZMDI recommends logging of registers 10HEX to
13HEX data in the calibration log.
Functional
Description
June 30, 2014
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
32 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
5.2.1. Traceability
ZMDI can guarantee the EEPROM contents for packaged parts only; at delivery of bare dice, the EEPROM
content might be changed by flipped bits because of electrostatic effects, which could occur during the wafer
sawing.
The ZSC31150 contains three 16-bit registers reserved for user data; e.g., for an ID number. There are no
2
restrictions for the content of these registers 10HEX / 11HEX / 12HEX; they can be read via I C™ at any time.
When using ZACwire



TM
communication (OWI),
READ is possible if ZACwire™ communication is enabled
WRITE is possible if the EEPROM lock is disabled
WRITE is possible if an EEPROM error (wrong signature or multi-bit error) is detected
During final test, ZMDI writes the following manufacturing data to these registers:



Register 10HEX: bits 15:0 = lot number part 1 (MSB section
Register 11HEX: bits 15:5 = lot number part 2 (LSB section) / bits 4:0 = wafer number
Register 12HEX bits 15:8 = wafer x-position / bits 7:0 = wafer y-position
Table 5.2
temp
lotNbr
waferNbr
xpos
ypos
Lot, Wafer, x-Position, and y-Position Number Calculation Procedure
=
=
=
=
=
reg0x10 * 2048 + (reg0x11&0xFFE0)/32;
NumberConvert(temp, BASE); // BASE = 36
reg0x11&0x1F;
reg0x12&0xFF00)/256;
reg0x12&0x00FF;
ZMDI recommends saving these data in the calibration log to identify the device in the event that RMA processing
is needed.
Register 13HEX is used by ZMDI to store logistic data and internal information. It can be written by ZMDI via test
equipment only; the user cannot write data to this register.
EEPROM Error Correction
The EEPROM data are stored with HAMMING DISTANCE = 3, which means


100% detection and correction of 1-bit errors
100% detection of 2-bit errors
The detection of multi-bit errors (>2 bit) is processed at a lower detection rate.
Functional
Description
June 30, 2014
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
33 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
5.2.2. Configuration Words
The data stored in RAM and EEPROM in the registers at addresses 0BHEX to 0EHEX determine the configuration of
the ZSC31150 as described in the following tables.
Table 5.3
Bit
Configuration Word CFGAFE
Default at CFGAFE - Configuration of analog front-end
Delivery
15
0BIN
14:10
0 0000BIN
EEPROM/RAM Address 0BHEX
Bridge sensor (e.g., Pressure) channel eXtended Zero Compensation POLarity
(offset compensation by analog front-end; refer to section 2.1)
0: negative – compensates positive offsets
1: positive – compensates negative offsets
PXZCPOL
Bridge sensor (e.g., Pressure) channel eXtended Zero Compensation value
(offset compensation by analog front-end; refer to section 2.1)
PXZC
Offset compensation is only active if PXZC  0.
The value of one compensation step depends on the selected input span.
9:6
0000BIN
Bridge sensor (e.g., Pressure) channel GAIN (aIN; refer to section 2.1)
0000:
0001:
0010:
0011:
0100:
5
0BIN
420
280
210
140
105
0101:
0110:
0111:
1000:
70
52.5
35
26.25
1001:
1010:
1011:
11dd:
PGAIN
14
9.3
7
2.8
Enable AD Converter clock divider
ADCSLOW
Influences only the internal frequency of the A/D conversion.
Integration time is doubled to enhance the conversion result quality (less noise, better
linearity).
0: fADC = fCLK
1: fADC = fCLK / 2
4:3
10BIN
AD Conversion input Range Shift for measured signal
(RSADC; see section 2.1)
00:
01:
10:
11:
2:1
01BIN
/16  ADC range
/8  ADC range
¾  ADC range
½  ADC range
15
7
ADCRS
= [(–1/16 VADC_REF ) to (+15/16 VADC_REF)]
= [ (–1/8 VADC_REF ) to (+7/8 VADC_REF)]
= [ (–1/4 VADC_REF ) to (+3/4 VADC_REF)]
= [ (–1/2 VADC_REF ) to (+1/2 VADC_REF)]
AD Conversion RESolution (rADC; refer to section 2.1)
ADCRES
Valid for both bridge sensor and temperature measurement.
00: 13 bits
10: 15 bits
01: 14 bits
11: 16 bits
If 15 bits or 16 bits are activated, use CFGAPP:POFFS to select the segment used for the
bridge sensor signal. Conditioning calculation is done with a 13-bit or 14-bit input value
respectively.
0
1v
AD Conversion ORDer
0:
Functional
Description
June 30, 2014
1-step conversion
ADCORD
1:
2-step conversion
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 5.4
Configuration Word CFGAPP
Bit
Default
15:13
000BIN
CFGAPP - Configuration of target application
EEPROM/RAM Address 0CHEX
Bridge sensor (e.g., Pressure) measurement segment.
POFFS
Digital offset to raw bridge sensor measurand value
12
0BIN
Ratio of bridge sensor (e.g., Pressure) measurements to special measurements in cycle:
0:
1 bridge sensor and 1 special
1:
PCNT
30 bridge sensor and 1 special
11
0BIN
Enable ROM check at power-on. Start-up time is increased by approximately 10ms.
0: disabled
1: enabled
CHKROM
10
1BIN
Enable increased limit for sensor short check.
0: limit = 1750 counts
1: limit = 2280 counts
CHKSSCL
9
0BIN
Enable sensor connection and short check.
0: disabled
1:
CHKSENS
8
0BIN
Enable Temperature sensor check. *
0:
7:6
01BIN
disabled
0BIN
CHKTS
1:
enabled
Temperature measurement GAIN (refer to section 6).
00: GT1
5
enabled
01: GT2
10: GT3
TGAIN
11: GT4
Temperature Measurement Mode
TMM
At sensor voltage excitation (CSBE=0) AND with external temperature measurement
(TINT=0), determination of temperature measurement mode for external TS.
0: diode
1: external voltage
Otherwise at sensor bridge current excitation (CSBE=1) OR at internal temperature
measurement (TINT=1), adjust temperature measurement zero point ZCT; adjustment
correlates with ADJREF:TOFFS.
0: zero point TOFFS=0
1: zero point TOFFS=2
4
3
1BIN
1BIN
Temperature measurement internal
0: external (diode or voltage)
TINT
1:
on-chip diode
Bridge current excitation (CSBE=1): enable common mode regulation
Bridge voltage excitation (CSBE=0):
CMSHE
Connect internal VSSA to VBR_B and VDDA to VBR_T
0: disabled/disconnected
1: enabled/connected
2
0BIN
Sensor bridge excitation mode:
0: voltage excitation
CSBE
1:
current excitation
1
0BIN
ADC and XZC reference voltage (VADC_REF; refer to section 2.1):
0: VADC_REF = VVBR_T – VVBR_B
1: VADC_REF = VVDDA – VVSSA
BREF
0
0BIN
Bridge signal polarity (differential voltage at pins VBP and VBN):
0: positive (VIN_DIFF = VVBP – VVBN)
1: negative (VIN_DIFF = VVBN – VVBP)
BPOL
* Note: For product versions ZSC31150Cxx and earlier, bit 8 is CHKAGE, which is the enable bit for the Sensor Aging Check (CMV). Set to 1
to enable. The default is 0. For product versions ZSC31150Dxx and subsequent versions, the CMV check is controlled by the limits.
Functional
Description
June 30, 2014
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
35 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 5.5
Configuration Word ADJREF
Bit
Default
15:14
00BIN
ADJREF - Adjustment of internal references
EEPROM/RAM Address 0DHEX
One-Wire Interface Mode (refer to section 3.3 for details)
IFOWIM
Pin AOUT
Bits 15:14
13:10
1000BIN
9
0BIN
8:6
100BIN
OWI Mode
OWI
Analog Output
00
OWIWIN
Start-up window
After start-up window
01
OWIANA
Start-up window
Enabled
10
OWIENA
Enabled
Disabled
11
OWIDIS
Disabled
Enabled
2
Additional alternative SIF slave address for I C™ and OWI.
IFADDR
3 MSB bits (70HEX) are added to 4 programmable LSB bits (resulting range 70 HEX to 7FHEX,
default address 78HEX is also valid).
Enable reset in case of Diagnostic Mode (executed after time-out of the watchdog timer)
0: stop, hold in DM
1: reset, start-up again
ZCT adjustment value
Sensor bridge voltage excitation (CFGAPP:CSBE=0)

Adjustment for zero point of temperature measurement ZCT
(refer to section 6.1 for details).
Sensor bridge current excitation (CFGAPP:CSBE=1)

Adjustment for sensor bridge current.
Supply current depends on external reference resistor RIBR.
IBR,nom = VVDDA / (16 RIBR).
IBR is adjustable in 0.125 IBR,nom units in the range of 0.5 to 1.375 IBR,nom .
Default value causes factor 1 (IBR,nom).
5
1BIN
4:0
10010BIN
Functional
Description
June 30, 2014
DMRES
TOFFS
CSBADJ
Enables bias current boost for analog front-end (recommended fCLK > 3MHz)
0: disabled
1: enabled
BBOOST
Adjusts frequency fOSC’ of internal oscillator (default: 3MHz  20%).
Adjustment of fCLK in the range of 2 to 4MHz. (Only applicable for OWI communication.)
OSCADJ
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 5.6
Bit
Configuration Word RESERVED
Default at RSVD – Additional adjustments
delivery
15:4
000HEX
Do not use
3
0BIN
Do not use
2
0BIN
Do not use
1
0BIN
Enables enhanced bridge settling mode
0: disabled
0
5.3.
0BIN
EEPROM/RAM Address 0EHEX
BSETTL
1:
enabled
Enables EEPROM lock for OWI communication
0: disabled
1: enabled
EEPLOCK
EEPROM Signature
The EEPROM signature (address FHEX) is used to check the validity of EEPROM contents. The signature is built
using a polynomial arithmetic modulo 2. The following source code generates the signature if the field eepcont[ ]
is allocated by the EEPROM contents (addresses 00HEX to 0EHEX). The parameter is the count of addresses
included in the signature and must be set to N=15 for the ZSC31150.
Figure 5.1 Source-Code Signature Generation
#define POLYNOM 0xA005
unsigned short signature(eepcont, N)
unsigned short eepcont[], N;
{
unsigned short sign, poly, p, x, i, j;
sign = 0; poly = POLYNOM;
for (i=0; i<N; i++) {
sign^=eepcont[i];
p=0; x=sign&poly;
for (j=0; j<16; j++, p^=x, x>>=1);
sign<<=1; sign+=(p&1);
}
return(~sign);
}
Functional
Description
June 30, 2014
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
5.4.
EEPROM Write Locking
Product versions ZSC31150Dxx and later support EEPROM write locking. If the mode is active
(RSVD:EEPLOCK=1), it is not possible to overwrite the current EEPROM content using the OWI interface and the
ZSC31150 responds with error code CF6CHEX. An activated EEPROM lock (RSVD:EEPLOCK=1) can be always
2
overwritten using I C™ communication.
An EEPROM lock programmed in EEPROM is activated by
1) New power-on
2) Sending the EEP_WRITE_EN command
3) Start measurement cycle by a STRT_CYC_xxx command
The following write sequence is possible:
1) Write calibration data including EEPLOCK to RAM mirror
2) Copy RAM mirror to EEPROM
3) Write EEPROM signature directly to EEPROM
In the case of a wrong EEPROM signature, the EEPROM lock is always deactivated.
6
Temperature Sensor Adaption and CMV Measurement
Temperature measurement data can be acquired from different temperature sensors (TS), which are adjusted by
configuration registers CFGAPP and ADJREF. CFGAPP:TMM and CFGAPP:TINT define the temperature sensor
to be used for acquiring temperature data. CFGAPP:TGAIN, ADJREF:TOFFS, and CFGAPP:TMM are used to
adapt/fit the signal range of the sensor to the input properties and operation temperature range. The range shift
for the A/D conversion is always set to ½ (refer to section 2.1). Table 6.1 shows recommended and possible
configurations for different types of temperature sensors.
Table 6.1
Configuration Temperature Measurement
Gain
TGAIN
Zero Point
Adjustment
ZCT
Internal Diode
GT1 – GT4
0 or 2 (TMM)
External Diode
GT1 – GT4
0 to 7 (TOFFS)
VBR_T, IRTEMP
VTEMP = VIRTEMP - VVBR_T
TS zero point is adjusted by CFGAPP:TOFFS
External Resistor
GT1 – GT4
0 to 7 (TOFFS)
IRTEMP
Half bridge: VDDA to VSSA
TS zero point is adjusted by CFGAPP:TOFFS
No adjustment
5 or 7 (TMM)
Temperature
Sensor
Bridge TC
Sensor
Connected
to/between Pin(s)
Notes
Recommended: GT2 and ZCT=0
TS zero point is adjusted by CFGAPP:TMM
TS zero point is adjusted by CFGAPP:TMM
Note: The temperature sensor must be adjusted to ensure that at minimum and maximum temperature, the
temperature sensor output voltage (including tolerances!) is inside the specified input signal and ADC range.
Adjust the gain and offset within the temperature range so that the output of the ADC (START_AD_T_AZC,
command D9) is in the range of 10% to 90% of the minimum to maximum digital conversion result.
Functional
Description
June 30, 2014
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
38 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
6.1.
Temperature Measurement when Sensor Bridge is in Voltage Excitation Mode
6.1.1. Internal PN-Junction TS
Table 6.2
Sensitivity Internal Temperature Sensor
Sensitivity ppm FS / K
CFGAPP:TGAIN
Minimum
Typical
Maximum
GT1 (00)
1333
1466
1629
GT2 (01)
3332
3665
4072
GT3 (10)
3665
4032
4479
GT4 (11)
3998
4398
4887
The input range is typically shifted by 1/8 full scale higher for adjusting CFGAPP:TMM=1.
6.1.2. External PN-Junction TS
Adaptation of an external diode for temperature measurement is described in this section. The values given in
Table 6.3 are recommended for typical diodes within the temperature range. Measure the diode’s forward voltage
(VF) for the external pn-junction to make an adjustment; normally 650mV is expected. Typically VF changes
depending on the temperature by –2mV/K.
VT
12
13 VBR_T
14 IRTEMP
ZSC31150
Figure 6.1 External PN-Junction Temperature Sensor
Temperature Sensor
Table 6.3
Sensitivity and IRTEMP Input Signal Range in mV/V using External PN-Junction Mode
Sensitivity (SED) ppm FS / K
TGAIN
Functional
Description
June 30, 2014
Minimum
Typical
Maximum
GT1
606
667
741
GT2
1515
1667
1852
GT3
1667
1833
2037
GT4
1818
2000
2222
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
39 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 6.4
Temperature Measurement Input Range Midpoint in mV (RMED)
VT Input Range Midpoint in mV (RMED)
Zero Point Adjustment
(ZCT)
0
1
2
3
4
5
6
7
Minimum
533
500
467
433
400
367
333
300
Typical
667
625
583
542
500
458
417
375
Maximum
800
750
700
650
600
550
500
450
Calculation of input range for a given adjustment configuration (see Table 6.3 for SEDxxx):
Input range minimum:
IRmin = RMEDmin +/- 0.45/ SEDmax
Input range typical value:
IRtyp = RMEDtyp +/- 0.45/ SEDtyp
Input range maximum:
IRmax = RMEDmax +/- 0.45/ SEDmin
Input signal ranges are roughly estimated and must be verified in the application in the full application temperature range.
6.1.3. External Resistor
Figure 6.2 Temperature Measurement with External Resistor
R(T)
IRTEMP
ZSC31150
VT
VDDA
VDDA
VSSA
Half Bridge
The ZSC31150’s external resistor mode supports using an external half bridge for temperature measurement,
which is connected between VDDA and VSSA. Input signal range is asymmetric and begins at a maximum of
approximately 30%*VDDA less than VDDA (asymmetric input range, approximately 0.7 VDDA to 1 VDDA).
Table 6.5 explains the resulting input range for using an external resistor for temperature measurement in detail.
Because temperature measurement via an external resistor delivers a ratiometric result, the voltage VT is
displayed as a ratio to VDDA.
Functional
Description
June 30, 2014
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
40 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
Table 6.5
ZSC31150 Input Signal Range for External Resistor Mode (Voltages referenced to VDDA)
Sensitivity
TGAIN
ppm FS / [mV/V]
GT1
0
1
2
3
4
5
6
7
min
20
20
20
20
20
20
20
20
max
350
340
330
320
310
300
290
280
min
95
85
70
60
50
40
30
20
max
240
230
220
210
200
190
180
166
min
100
90
80
70
60
50
40
30
max
230
220
210
200
190
180
170
160
min
105
95
85
75
65
55
45
35
max
225
215
205
195
185
175
165
155
2666
GT2
6666
GT3
7333
GT4
Hint:
Temperature Zero Point Adjustment (register ADJREG:TOFFS)
VT / VDDA
[mV/V]
8000
IRTEMP input signal ranges are roughly estimated and must be verified in the application.
6.1.4. Result and Sensitivity Calculation
Temperature gain (TGAIN) and offset (ADJREF:TOFFS) are programmable for temperature acquisition; VOFFS is
the resulting shift potential of the offset adjustment. The temperature measurement result is compared to VT_REF
(depending on input mode) and can be calculated and verified by using the following gain coefficients (voltages
referenced to VSS):
Table 6.6
Temperature Gain Coefficients
Gain Identifier
GT1
GT2
GT3
GT4
GAIN
2.66
4.0
6.6
7.33
Functional
Description
June 30, 2014
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
6.2.
Temperature Measurement when Sensor Bridge in Current Excitation Mode
Bridge current excitation enables temperature measurements using the temperature coefficient of bridge
resistors, so no additional temperature sensor is needed. For temperature data acquisition, the common mode
voltage of the bridge inputs (VBP and VBN) is measured.
The bridge current must be adjusted with restricted voltage over the bridge VBridge and the input signal VVBN and
VVBP must be in the allowed range, which can be secured by an internal control circuit. The bridge current can be
coarsely tuned by adding an external resistor from the VBR_T pin to the top of the bridge and finely adjusted by
changing the configuration register ADJREF:CSBADJ to ensure that the common mode range is not exceeded
when considering the full temperature behavior and measured rejection limits.
Figure 6.3 Bridge Current Mode Application
VDDA
VDDA
VBridge
VBP
VBN
VBR_B
Sensor Bridge
ZSC31150
VBR_T
VSSA
Table 6.7 gives the input sensitivity and range with respect to VBridge/VDDA for bridge signal measurements in
Bridge Current Excitation Mode for temperature measurements.
Table 6.7
TGAIN
GT1
GT2
GT3
GT4
Functional
Description
June 30, 2014
Temperature Measurement in Bridge Current Excitation Mode (CFGAPP:CSBE=1)
Sensitivity
ppm FS / [mV/V]
VBridge / VDDA
[mVV]
Temperature Zero Point Adjustment (register CFGAPP:TMM)
TMM=0
TMM=1
Min
0
0
Max
1000
1000
Min
163
319
Max
1000
1000
Min
195
338
Max
1000
1000
Min
203
328
Max
923
1000
444
889
1067
1333
© 2014 Zentrum Mikroelektronik Dresden AG — Rev. 1.07
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prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
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ZSC31150
Fast Automotive Sensor Signal Conditioner
6.3.
CMV Measurement
ZSC31150 offers a special method for sensor aging detection. The common mode voltage (CMV) of the sensor
bridge is periodically measured during NOM and compared with limits that are defined during calibration for this
function. Limits are stored in register 0AHEX. The 16 bits of this register are divided into two sections. The lower
limit is stored at bits [7:0] and the upper limit is stored at bits [15:8] of register 0AHEX. A CMV error is indicated if
the current CMV measurement result is lower than the lower limit or higher than the upper limit.
The CMV limits can be expressed as percentages of the CMV measurement result (START_AD_CMV_AZC,
command DB) or calculated directly with the following CMV_AZC formula. When defining CMV limits, note that
the CMV measurement result can drift in the temperature range depending on the temperature behavior of the
sensor bridge. The CMV measurement acquires the common mode voltage of bridge (VIN_CM) and can be approximated using following formulas:
 Approximated CMV measurement
 8  VIN_CM
CMV_AZC  2RES  
 3  VBR



5
  T1AZ  2RES  

6

Ideal Case T1AZ  2RES1


 4  VIN_CM
CMV_AZC  2RES   2
 1
 3  VBR

RES
ADC resolution in bits
(RES =[13|14|15|16])
T1AZ
AZ readout of T1 measurement
(Command D5)
VIN_CM
Common mode voltage at input
(shorted VBP and VBN)
VBR
VBR_T – VBR_B = bridge
(supply) voltage
The EEPROM register content for upper and lower limits can be calculated using the following equations:
 Upper Limit
 CMV_AZC
8196 * CMVlim it _ high
CMVbits 15:8   Hex 
 4096 
RES 13
100
 2


  32  1



RES
ADC resolution in bits
(RES = [13|14|15|16])
CMVlimit_high
Percentage value for
upper CMV limit
range = [0 to 25] %
CMVlimit_low
Percentage value for
lower CMV limit
range = [0 to 25] %
 Upper Limit
 CMV_AZC
8196 * CMVlim it _ low
CMVbits 7:0   Hex 
 4096 
RES 13
100
 2


  32



RES-13
The factor of 2
is used to shift the result of the CMV_AZC measurement to the internal 13-bit domain that is
used for comparison with predefined CMV limits.
Functional
Description
June 30, 2014
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
43 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
6.4.
Sensor Check
The sensor check consists of two parts: the Sensor Connection Check (SCC) and Sensor Short Check (SSC).
These two options can only be enabled or disabled together because both options are controlled via
CFGAPP:CHKSENS (refer to Table 5.4). Both options will directly influence the response time of the whole system. For details about response time, refer to the ZSC31150 Bandwidth Calculation Spreadsheet.
The Sensor Connection Check will check if one of the four connection wires of the sensor bridge is broken. This
option enables additional comparators that will monitor both differential inputs of the sensor bridge. An internal
current supply will bring the VBR_T line to a defined voltage level to avoid misinterpretations if the VBR_T line is
not connected.
Figure 6.4 illustrates the principle of Sensor Short Check. If SSC is enabled, two additional measurement tasks
(SSC+ and SSC-) are added into the measurement cycle, which are described in the ZSC31150 Data Sheet.
During the measurement, a current is forced into the bridge by internal current sources. The voltage difference
between VBP and VBN is measured. If voltage difference is too small, then a shorted sensor is detected. In order
to avoid misinterpretations during measuring, which could be caused by the voltage difference of the sensor
bridge, the SSC measurement with same current level is repeated but with a reverse sign.
Figure 6.4 Principle of Sensor Short Check
µA
VBN
11 VBR_B
12
VBP
µA
ZSC31150
10
13 VBR_T
Sensor Bridge
Functional
Description
June 30, 2014
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
44 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
7
Related Documents
Note: X_xy refers to the current revision of the document.
Document
File Name
ZSC31150 Data Sheet
ZSC31150_Data_Sheet_Rev_X_xy.pdf
ZSC31150 Evaluation Kit Description
ZSC31150_Evaluation_Kit_Description_Rev_x_yy.pdf
SSC Application Note - Single Ended Input *
SSC_AN_Single_Ended_Input_Rev_x_yy.pdf
ZMDI Wafer Dicing Guidelines
ZMDI_Wafer_Dicing_Guidelines_Rev_X_xy
ZSC31150 Bandwidth Calculation Spreadsheet **
ZSC31150_BandwidthCalculationRevX_xy
Calibration DLL Description****
RBIC_DLL_description.txt
SSC Command Syntax Spreadsheet***
SSC_CB_Command_Syntax_for_CommBd_Firmware_V4_04.xlsx
Visit the ZSC31150 product page www.zmdi.com/zsc31150 on ZMDI’s website www.zmdi.com or contact your
nearest sales office for the latest version of these documents.
Note: Documents marked with an asterisk (*) require a login account for access on the web. For detailed instructions, visit www.zmdi.com/login-account-setup-procedure.
Note: Documents marked with a double asterisk (**) are only available upon request. For these documents,
please contact ZMDI (see contact information on page 47).
Note: Documents marked with three asterisks (***) are available on the ZMDI SSC Tools web page:
www.zmdi.com/ssc-tools
Note: Documents marked with four asterisks (****) are text files available in the program folder on the user’s PC
after installation of the ZSC31150 Evaluation Software.
8
Glossary
Term
Description
ADC
Analog-to-Digital Converter
AOUT
Analog Output
BR
Bridge Sensor Signal Measurand (e.g., Pressure)
CM
Command Mode
CMC
Calibration Microcontroller
CMV
Common Mode Voltage
CRC
Cyclic Redundancy Check
DAC
Digital-to-Analog Converter
DM
Diagnostic Mode
EEPROM
Electrically Erasable Programmable Read Only Memory
Functional
Description
June 30, 2014
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
45 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
Term
Description
LDR
Lower Diagnostic Range
LPF
Low-Pass Filter
MSB
Most Significant Bit
NOM
Normal Operation Mode
OWI
One-Wire Interface
RAM
Random-Access Memory
ROM
Read Only Memory
SCC
Sensor Connection Check
SED
Sensitivity External Diode
SIF
Serial Interface
SSC
Sensor Short Check or Sensor Signal Conditioner (depending on context)
SSC+
Positive-Biased Sensor Short Check
SSC-
Negative-Biased Sensor Short Check
TS
Temperature Sensor
UDR
Upper Diagnostic Range
XZC
eXtended Zero Compensation
Functional
Description
June 30, 2014
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
46 of 47
ZSC31150
Fast Automotive Sensor Signal Conditioner
9
Document Revision History
Revision
1.00
Date
Description
September 25, 2009
First release of document.
October 2, 2009
Change to ZMDI denotation.
1.03
July 29, 2010
Table 5.4: TMM explained more in detail. Table 4.2: Low byte of SIF2 at
START_AD_xx command changed to processed command.
Rearrangement of formulas in section 6.3  renamed common mode voltage.
Section 2.5: Added a more detailed description.
Section 4.5.1: Added a more detailed description of START_CM command.
Inserted new drawings for Figure 1.1, Figure 3.2, Figure 3.3, Figure 3.7, Figure 3.8.
Corrected default value in Table 5.6 for bits 15:4 to “000HEX.”
Section 8: extended glossary. Applied new ZMDI template.
Renamed RREF in section 6.2 and RBR_REF in Table 5.5 into RIBR as in DS.
Renamed the ZMD31150 as the ZSC31150.
1.04
May 16, 2011
Corrected CMV equation for ideal case in section 6.3. Corrected measurement tasks
to SSC+ and SSC- in section 6.4. Extended working mode description (1.3) and
START_CM description (4.5.1). Corrected Figure 6.2 and redrew Figure 6.1 and
Figure 6.3. Added more detailed description for OWI bit time (tOWI_Bit) and OWI hold
time start condition (tOWI_STA).
1.05
May 26, 2011
Add detailed description for CMV limit calculation and EEPROM registers 8HEX/9HEX.
1.06
August 7, 2013
Sed_DAC command behavior and formulas added. Added detailed description for
CMV limit calculation and EEPROM registers 8HEX/9HEX. Added extend description of
AD segmentation. Revision to Table 6.3. Added definition of SED to glossary. Added
range shift definition for temperature measurement.
1.07
June 30, 2014
Segmentation section updated. Correction for Range Shift values in calculation
formulas. OWI interface parameters extended. Updates for Table 3.2 and text below.
Update for specification for tOWI_STO in Table 3.3.
Contact phone numbers and related documents section updated. Minor edits for
clarity.
1.01-1.02
Sales and Further Information
www.zmdi.com
[email protected]
Zentrum Mikroelektronik
Dresden AG
Global Headquarters
Grenzstrasse 28
01109 Dresden, Germany
ZMD America, Inc.
1525 McCarthy Blvd., #212
Milpitas, CA 95035-7453
USA
Central Office:
Phone +49.351.8822.306
Fax
+49.351.8822.337
USA Phone 1.855.275.9634
Phone +1.408.883.6310
Fax
+1.408.883.6358
European Technical Support
Phone +49.351.8822.7.772
Fax
+49.351.8822.87.772
DISCLAIMER: This information applies to a product under development. Its characteristics and specifications are subject to change without notice.
Zentrum Mikroelektronik Dresden AG (ZMD AG) assumes no obligation regarding future manufacture unless otherwise agreed to in writing. The
information furnished hereby is believed to be true and accurate. However, under no circumstances shall ZMD AG be liable to any customer,
licensee, or any other third party for any special, indirect, incidental, or consequential damages of any kind or nature whatsoever arising out of or
in any way related to the furnishing, performance, or use of this technical data. ZMD AG hereby expressly disclaims any liability of ZMD AG to any
customer, licensee or any other third party, and any such customer, licensee and any other third party hereby waives any liability of ZMD AG for
any damages in connection with or arising out of the furnishing, performance or use of this technical data, whether based on contract, warranty,
tort (including negligence), strict liability, or otherwise.
European Sales (Stuttgart)
Phone +49.711.674517.55
Fax
+49.711.674517.87955
Functional
Description
June 30, 2014
Zentrum Mikroelektronik
Dresden AG, Japan Office
2nd Floor, Shinbashi Tokyu Bldg.
4-21-3, Shinbashi, Minato-ku
Tokyo, 105-0004
Japan
ZMD FAR EAST, Ltd.
3F, No. 51, Sec. 2,
Keelung Road
11052 Taipei
Taiwan
Phone +81.3.6895.7410
Fax
+81.3.6895.7301
Phone +886.2.2377.8189
Fax
+886.2.2377.8199
Zentrum Mikroelektronik
Dresden AG, Korea Office
U-space 1 Building
11th Floor, Unit JA-1102
670 Sampyeong-dong
Bundang-gu, Seongnam-si
Gyeonggi-do, 463-400
Korea
Phone +82.31.950.7679
Fax
+82.504.841.3026
© 2014 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 the
prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
47 of 47