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 Document Feedback 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 Page 2 Document Feedback 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 Document Feedback 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 Document Feedback 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 Document Feedback 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 Page 6 Document Feedback 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 Document Feedback 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 Document Feedback 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 Page 9 Document Feedback 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 Document Feedback 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 Document Feedback 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 Page 12 Document Feedback 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 Document Feedback 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 Document Feedback 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 Document Feedback HLS-442 − Mechanical Information Mechanical Information Dimensions Figure 17: Sensor Dimensions RoHS Green Note(s) and/or Footnote(s): 1. Dimensions are in millimeters. Page 16 Document Feedback 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 Page 17 Document Feedback 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. Page 18 Document Feedback 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 Page 19 Document Feedback HLS-442 − Document Status Document Status Document Status Product Preview Preliminary Datasheet Datasheet Datasheet (discontinued) Page 20 Document Feedback 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 Page 21 Document Feedback HLS-442 − Content Guide Content Guide Page 22 Document Feedback 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