HLS-442

HLS-442
Automotive Hydrogen Leak Sensor
General Description
The HLS-442 automotive hydrogen leak sensor monitors
hydrogen concentrations of 0 – 4.4% in air. The sensor is a leak
sensor developed in accordance to IEC 61508 (SIL2) and
explosion protected according to ATEX 100a. The predicted
concentration is transmitted to the host via the CAN bus
interface. HLS-442 utilizes self-calibration that is performed
automatically when operated in air with normal hydrogen
concentration. Therefore, the HLS-442 should not continuously
be operated in elevated background levels of
hydrogen.
Ordering Information and Content Guide appear at end of
datasheet.
Key Benefits & Features
The benefits and features of HLS-442, Automotive Hydrogen
Leak Sensor are listed below:
Figure 1:
Added Value of Using HLS-442
Benefits
Features
• High sensitivity and excellent
selectivity to hydrogen gas
• 0–4.4% H2 in air
• Accuracy ±3000 ppm at normal operation
• Low cross sensitivity
• Heated field-effect transistor technology
• No detection towards HC, H2S, N2, CO, CO2, NOx, H2O
• Humidity influence not detectable
• Fast response time
•
•
•
•
•
• Low power consumption
• 75 mA (typical)
• Long-term stability and reliability
• ESD and EMC protection
• Operating temperature range –40ºC to 85ºC
• Safety integrity level and explosion
proof
• Designed for SIL2 (IEC 61508) and ATEX 100a zone 2
• Long lifetime
• IP67 qualified with expected lifetime of 10 years
ams Datasheet
[v1-00] 2015-Mar-30
Start-up time <5s
Speed of response (t90) < 2s
Speed of recovery < 10s
CAN bus interface 500 kbit/s (ISO11898-2)
PWM output (on request)
Page 1
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HLS-442 − General Description
Applications
Detection of hydrogen gas leaks in hydrogen powered vehicles
by installing the sensor
• in the cabin ceiling
• under the hood of the engine compartment
• beneath the trunk lid of hydrogen powered vehicles
Detection of hydrogen gas in and around hydrogen fueling
stations
Block Diagram
The functional blocks of this device for reference are
shown below:
Figure 2:
HLS-442 Block Diagram
Timer
μController
Watchdog
Output Switch
Connector
Power Supply
Heater Switch
Resistor
H2-Sensor
Quantity (TC)
Resistor
H2-Sensor
Plausibility (FE)
LDO Voltage Regulation
Heater Switch
EMC Filter
Protection
Overvoltage, reverse polarity
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − General Description
Figure 3:
HLS-442 Overview
Power and
CAN bus
connector
Gasket 7 164 300
Gas inlet filter
Mounting holes
ams Datasheet
[v1-00] 2015-Mar-30
Page 3
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HLS-442 − General Description
Installation
The HLS-442 is designed for either a sealed installation against
a wall (using a gasket) [Alt. 1] or an open-air [Alt. 2] installation.
The sensor can be oriented in any direction but the gas inlet
must not be blocked.
Retaining pins or bolts shall be max Ø5.5 mm.
Maximum mounting torque 10 Nm.
Figure 4:
Mounting Positions
Alt. 1
Alt. 2
Page 4
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Electrical Interface
Electrical Interface
Electrical Connector
The sensor connector is A2100011199, 6-PIN Code A. Matching
receptacle is a 6-pin MQS, TE Connectivity AMP p/n 1-967616-1
type A.
Figure 5:
Pin Coding AMP 1-967616-1 Type A
1 2 3
4 5 6
Figure 6:
Pin Assignment
ams Datasheet
[v1-00] 2015-Mar-30
Pin
Function
1
CAN – High
2
CAN – Low
3
Power UB0
4
Power UB1
5
Power UB2
6
GND
Page 5
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HLS-442 − Electrical Inter face
CAN Bus Interface
This section describes the CAN bus interface that is available in
some variants of HLS-442.
Physical Interface
The physical interface is two-wire balanced, non-terminated. It
is a high speed CAN interface (ISO 11898-2) with bus bit rate of
125, 250 or 500 kBit/s, depending on the variant of HLS-442.
Bus Identification
Each sensor and the control unit are identified on the bus by
the CAN identity, CAN ID. The CAN ID is transmitted in the CAN
data frame arbitration field. For the sensors the CAN ID is
determined by the configuration of the power supply feeds,
UB0 (pin 3), UB1 (pin 4) and UB2 (pin 5). The table below defines
the sensor’s CAN ID, VB denotes a power input connected to
supply voltage level. Addresses are given in hexadecimal
numbers and denoted with a leading “0x”.
Figure 7:
Overview CAN ID Assignment By Power Supply Feeds
UB2
UB1
UB0
Sensor Number
CAN ID
VB
1
0x640
2
0x648
3
0x650
4
0x658
5
0x660
6
0x668
7
0x670
VB
VB
VB
VB
VB
VB
VB
VB
VB
VB
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VB
ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Electrical Interface
Messages From the Sensor
The main message sent from the sensor to the control unit is
the Sensor Status Message, hereafter referred to as the SSM.
After 700 ms from power-ON of the sensor it will start sending
the SSM frame as defined below. The SSM, after this event, is
transmitted periodically with a 100 ms interval until the sensor
is powered OFF. Besides the SSM, the sensor can also send a
Wake-Up pulse. This is described in detail in Wake-Up Function.
The Wake-Up pulse is separate from the SSM and has no impact
on the SSM.
The figure below defines the data field of the SSM CAN data
frame. The data field uses 8 bytes. The CAN ID as described
earlier sets the arbitration field.
Figure 8:
CAN Matrix Message Layout
Parameter
Name
Data
Size
Physical
Measurement
Range
Value
Range
H2
Concentration
8 bits
0 – 4.4 %
[20 -240]
Protection
Value 1
b7
b6
b5
b4
b3
b2
b1
b0
Byte
No.
H2 Concentration
0
8 bits
pv1
1
FE high
8 bits
FE high
2
CRC16 Byte 1
(Higher Byte)
8 bits
CRC16
3
FE low
2 bits
Protection
Value 2
2 bits
Sensor
Number
3 bits
[1 - 7]
Msg. Counter
8 bits
[0 - 255]
Sensor status
2 bits
[0 - 3]
Part number
5 bits
[1 - 31]
CRC16 Byte 2
(Lower Byte)
8 bits
ams Datasheet
[v1-00] 2015-Mar-30
FE low
4
0
pv2
UB
2
UB
1
4
UB
0
4
Msg Counter
5
status
Part number
CRC16
0
6
0
6
7
Page 7
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HLS-442 − Electrical Inter face
H 2 Concentration
0% is encoded with decimal number 20.
4.4% (44000 ppm) is encoded with decimal number 240.
The relation between detected H 2 concentration (in ppm) and
concentration code as signaled in the message is:
(EQ1)
Code = round(H 2/200) + 20
(EQ2)
H 2 = (code – 20)*200
Where round() denotes rounding towards the nearest integer.
Protection Value
The protection value offers a 10-bit consistency check of the
transmitted concentration, status and message counter. The
following pseudo code describes the algorithm forming the
10-bit value and how it is projected on to the protection value
1 and the protection value 2 bytes in the SSM.
code[7 - 0] denotes the set of 8 bits transmitted as code for
representing the H 2 concentration.
status[1 - 0] denotes the set of two bits transmitted as code for
representing sensor status.
mgscnt[6 - 0] denotes the set of 7 bits transmitted as code for
representing message counter.
pv[9 - 0] denotes the set of 10 bits forming the protection value.
pv1[7 - 0] denotes the set of 8 bits transmitted as code for
protection value 1.
pv2[1 - 0] denotes the set of 2 bits transmitted as code for
protection value 2.
Page 8
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Electrical Interface
Figure 9:
Pseudo Code Description of Protection Value
Pseudo Code
Description
pv[9 - 8] = status[1 - 0]
Assign two most significant bits of pv as the status bits
pv[7 - 0] = code[7 - 0]
Assign 8 least significant bits of pv as the code bits
pv[9 - 0] = pv[9 - 0] +
msgcnt[1 - 0]
To pv add the number formed by two least significant bits of the message
counter
pv[9 - 0] = NOT pv[9 - 0]
Perform bitwise inverse of pv
pv[9 - 0] = pv[9 - 0] + 1
To pv add 1
pv1[7 - 0] = pv[7 - 0]
Form protection value 1 of the 8 least significant bits of the 10-bit
protection value
pv2[1 - 0] = pv[9 - 8]
Form protection value 2 of the 2 most significant bits of the 10-bit
protection value
FE High / FE Low
The raw FE signal is available in 10-bit resolution (1 step = 4mV).
The high 8 bits are available in byte 2 and the lower 2 bits in
byte 7, bit 6-7. The data range is 0-4092mV.
CRC16
Byte 3 and byte 7 form a 16-bit CRC value. The CRC is CCITT
CRC16.
Sensor Number
Sensor Number is defined by power supply feeds and CAN ID
assigned sensor number is repeated in byte 4 bit 2-4. The value
sent is given in Bus Identification.
Message Counter
The message counter is incremented by 1 after each
transmission of a SSM frame. After the counter reaches 255 it
wraps around and the next transmitted counter value
becomes 0. At sensor start-up the message counter begins at 1.
ams Datasheet
[v1-00] 2015-Mar-30
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HLS-442 − Electrical Inter face
Status
The figure below defines the status encoding of b1 and b2:
Figure 10:
The Status Encoding of b1 and b2
Status
Encoding b2:b1
Name
Description
0
0:0
No error
Sensor fully functional
1
0:1
Minor error
Main function ensured, but possible impairment
of measuring quality.
2
1:0
Minor functional error
Main function ensured, but impaired (the sensor
should be replaced)
3
1:1
Fatal functional error
Sensor is not functioning correctly.
Part Number
The part number defines the release number encoding of
b3-b7.
PWM
This section describes the PWM output that is available on
request for the HLS-442.
Physical Interface
The electrical connector is the same as in the variants with CAN
bus interface (see Electrical Connector). The power can be
applied to any of pin 3–5 (Power UB0–UB2). In the case of PWM
output, it does not matter which of these pins that are used.
The PWM signal is created as a differential CAN signal on pin 1
and 2. A CAN signal is said to be in a dominant state when the
signal lines are separated (a dominant bit is transmitted). When
the signal lines are at the same voltage level, the state is
recessive. Recommended circuitry to convert CAN signals to
TTL is specified in a separate document, available on request.
The PWM signal is only an output signal. No messages can be
sent to the sensor.
The PWM Signal
The PWM signal has a period time of 255 μs. The rather short
period is chosen since modern CAN transceivers do not allow
for a longer dominant state.
The duration of the recessive state can be translated into output
H 2 prediction from the sensor module. The recessive duration
(pulse width) ranges from 20 to 240 μs, which corresponds to 0
to 4.4% hydrogen. An internal error is shown as a 10 μs pulse
width.
The figure below shows the output for 0% hydrogen (pulse
width of 20 μs).
Page 10
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Electrical Interface
Figure 11:
Sensor Output for 0% Hydrogen (Pulse Width of 20 μs)
The relation between detected H 2 concentration (in ppm) and
pulse width (in μs) is:
(EQ3)
H 2 = (pulse width – 20)*200
The figure below shows the relation between H 2 prediction and
pulse width.
Figure 12:
The Relation between H2 Prediction and Pulse Width
ams Datasheet
[v1-00] 2015-Mar-30
Pulse Width
Message Type
10 μs
Error
20 μs
0% H2
21 μs
0.02% H2
...
...
239 μs
4.38% H2
240 μs
4.4% H2
Page 11
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HLS-442 − Specifications
Specifications
Figure 13:
Typical Characteristics
Description
Value
Sensor Function
Target gas
Hydrogen (H2)
Concentration range
0 – 4.4% H2 in air
Accuracy
± 3000 ppm
Resolution
200ppm
Speed of response (t90)
<2s
Speed of recovery
<10s
Cross-sensitivity
None towards HC, H2S, N2, CO, CO2, NOx Low humidity
influence during a H2 event. None in air.
Start-up time (1)
<5s, first message after 700 ms
Expected lifetime
10 years
Safety
Safety Integrity level
Designed for SIL2
Explosion proof
Designed for ATEX zone 2
Self test/Error handling
Yes
Electrical
Supply voltage
9V – 16V
Supply current
75mA typical
CAN interface (1)
ISO 11898 Version 2.0 b
Programmable CAN ID (1)
on request
CAN bit rate (kbit/s) (1)
standard 500 (on request 125, 250)
PWM Output (1)
on request
Connector
A2100011199, 6-PIN Code A
Mating Connector
MQS 6-pin, AMP p/n 1-967616-1 type A
ESD/Reverse polarity
Yes
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Specifications
Description
Value
Environmental
Operation temperature range
-40ºC to 85ºC
Storage temperature range
-50ºC to 85ºC
Humidity
5-95% (non-condensing)
Pressure
70-130 kPa
EMC
Automotive requirements
IP code
IP6K7
Mechanical
Dimensions (LxWxH)
82.2x42x17.3mm
Weight
50g
Material
PBT GF30
Filter membrane
Pall SUPOR 450R, 0.45 μm.
Note(s) and/or Footnote(s):
1. These features depend upon the version of HLS-442. See figure below
Figure 14:
Specification of the Different Variants of HLS-442
Description
Default
On Request
Start-up time
<5 s
CAN interface
Version 2.0 ISO 11898
n.a.
Programmable CAN ID
Pre-programmable on request
n.a.
CAN bit rate (kbit/s)
PWM output
ams Datasheet
[v1-00] 2015-Mar-30
500
125
-
250
n.a.
Yes
Page 13
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HLS-442 − Handling Instructions
Handling Instructions
Due to the fact that the sensor element consists of a silicon chip
facing the environment the following precautions have to be
taken into account:
Prevent sensor from:
• Humidity (condensing conditions)
• Dropping
• Dust
• Mechanical impact, especially the entrance membrane
• Electromagnetic radiation (RF fields, high magnetic fields
during storage)
Long term storage of sensors should be done in nitrogen filled
ESD bags to protect the sensor.
Page 14
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Reference Data
Reference Data
Figure 15:
Concentration Measurement with H2 Pulse Width of 2 min and Nominal Concentration 0.2%, 1.5%,
2.5% and 3.5% vol. H2
Figure 16:
Deviation of Prediction Over Nominal Concentration
ams Datasheet
[v1-00] 2015-Mar-30
Page 15
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HLS-442 − Mechanical Information
Mechanical Information
Dimensions
Figure 17:
Sensor Dimensions
RoHS
Green
Note(s) and/or Footnote(s):
1. Dimensions are in millimeters.
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Ordering & Contact Information
Ordering & Contact Information
Figure 18:
Ordering Information
Ordering Code
Type
Delivery Form
Delivery Quantity
HLS-442
CAN (500 kbit/s) (1)
Individually Wrapped
Single Item
Note(s) and/or Footnote(s):
1. For availability of other variants contact ams.
Buy our products or get free samples online at:
www.ams.com/ICdirect
Technical Support is available at:
www.ams.com/Technical-Support
Provide feedback about this document at:
www.ams.com/Document-Feedback
For further information and requests, e-mail us at:
[email protected]
For sales offices, distributors and representatives, please visit:
www.ams.com/contact
Headquarters
ams AG
Tobelbaderstrasse 30
8141 Unterpremstaetten
Austria, Europe
Tel: +43 (0) 3136 500 0
Website: www.ams.com
ams Datasheet
[v1-00] 2015-Mar-30
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HLS-442 − RoHS Compliant & ams Green Statement
RoHS Compliant & ams Green
Statement
RoHS: The term RoHS compliant means that ams AG products
fully comply with current RoHS directives. Our semiconductor
products do not contain any chemicals for all 6 substance
categories, including the requirement that lead not exceed
0.1% by weight in homogeneous materials. Where designed to
be soldered at high temperatures, RoHS compliant products are
suitable for use in specified lead-free processes.
ams Green (RoHS compliant and no Sb/Br): ams Green
defines that in addition to RoHS compliance, our products are
free of Bromine (Br) and Antimony (Sb) based flame retardants
(Br or Sb do not exceed 0.1% by weight in homogeneous
material).
Important Information: The information provided in this
statement represents ams AG knowledge and belief as of the
date that it is provided. ams AG bases its knowledge and belief
on information provided by third parties, and makes no
representation or warranty as to the accuracy of such
information. Efforts are underway to better integrate
information from third parties. ams AG has taken and continues
to take reasonable steps to provide representative and accurate
information but may not have conducted destructive testing or
chemical analysis on incoming materials and chemicals. ams AG
and ams AG suppliers consider certain information to be
proprietary, and thus CAS numbers and other limited
information may not be available for release.
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ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Copyrights & Disclaimer
Copyrights & Disclaimer
Copyright ams AG, Tobelbader Strasse 30, 8141
Unterpremstaetten, Austria-Europe. Trademarks Registered. All
rights reserved. The material herein may not be reproduced,
adapted, merged, translated, stored, or used without the prior
written consent of the copyright owner.
Devices sold by ams AG are covered by the warranty and patent
indemnification provisions appearing in its General Terms of
Trade. ams AG makes no warranty, express, statutory, implied,
or by description regarding the information set forth herein.
ams AG reserves the right to change specifications and prices
at any time and without notice. Therefore, prior to designing
this product into a system, it is necessary to check with ams AG
for current information. This product is intended for use in
commercial applications. Applications requiring extended
temperature range, unusual environmental requirements, or
high reliability applications, such as military, medical
life-support or life-sustaining equipment are specifically not
recommended without additional processing by ams AG for
each application. This product is provided by ams AG “AS IS”
and any express or implied warranties, including, but not
limited to the implied warranties of merchantability and fitness
for a particular purpose are disclaimed.
ams AG shall not be liable to recipient or any third party for any
damages, including but not limited to personal injury, property
damage, loss of profits, loss of use, interruption of business or
indirect, special, incidental or consequential damages, of any
kind, in connection with or arising out of the furnishing,
performance or use of the technical data herein. No obligation
or liability to recipient or any third party shall arise or flow out
of ams AG rendering of technical or other services.
ams Datasheet
[v1-00] 2015-Mar-30
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HLS-442 − Document Status
Document Status
Document Status
Product Preview
Preliminary Datasheet
Datasheet
Datasheet (discontinued)
Page 20
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Product Status
Definition
Pre-Development
Information in this datasheet is based on product ideas in
the planning phase of development. All specifications are
design goals without any warranty and are subject to
change without notice
Pre-Production
Information in this datasheet is based on products in the
design, validation or qualification phase of development.
The performance and parameters shown in this document
are preliminary without any warranty and are subject to
change without notice
Production
Information in this datasheet is based on products in
ramp-up to full production or full production which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade
Discontinued
Information in this datasheet is based on products which
conform to specifications in accordance with the terms of
ams AG standard warranty as given in the General Terms of
Trade, but these products have been superseded and
should not be used for new designs
ams Datasheet
[v1-00] 2015-Mar-30
HLS-442 − Revision Information
Revision Information
Changes from (2014-Dec) to current revision 1-00 (2015-Mar-30)
Page
Content of Applied Sensor datasheet was updated to the latest ams design
Note(s) and/or Footnote(s):
1. Page and figure numbers for the previous version may differ from page and figure numbers in the current revision.
2. Correction of typographical errors is not explicitly mentioned.
ams Datasheet
[v1-00] 2015-Mar-30
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HLS-442 − Content Guide
Content Guide
Page 22
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1
1
2
2
4
General Description
Key Benefits & Features
Applications
Block Diagram
Installation
5
5
6
6
6
7
8
8
9
9
9
9
10
10
10
10
10
Electrical Interface
Electrical Connector
CAN Bus Interface
Physical Interface
Bus Identification
Messages From the Sensor
H2 Concentration
Protection Value
FE High / FE Low
CRC16
Sensor Number
Message Counter
Status
Part Number
PWM
Physical Interface
The PWM Signal
12
14
15
Specifications
Handling Instructions
Reference Data
16
16
Mechanical Information
Dimensions
17
18
19
20
21
Ordering & Contact Information
RoHS Compliant & ams Green Statement
Copyrights & Disclaimer
Document Status
Revision Information
ams Datasheet
[v1-00] 2015-Mar-30