HLS-440P Automotive Hydrogen Leak Sensor The HLS-440P automotive hydrogen sensor monitors hydrogen General Description leakage concentrations of 0 - 10% in air. The design fulfills Zone 2 requirements according to ATEX 100a. The predicted concentration is transmitted to the host via the CAN bus interface or with PWM output. Type A: The sensor shall measure the hydrogen concentration in high humidity conditions, e.g. in the exhaust of a fuel cell system, to ensure compliance with defined upper thresholds. Type B: The sensor shall measure the hydrogen concentration under ambient humidity conditions, to ensure compliance with defined upper thresholds. Ordering Information and Content Guide appear at end of datasheet. Key Benefits & Features The benefits and features of HLS-440P, Automotive Hydrogen Leak Sensor are listed below: Figure 1: Added Value of Using HLS-440P Benefits Features 0 10% H in air or nitrogen 2 High sensitivity over large Accuracy 0.5% vol. concentration range Resolution 500ppm Heated field-effect transistor technology Low cross sensitivity No detection towards HC, H S, N , CO, CO , NO 2 2 2 x Humidity influence <0.5% typical Designed for humid environment Operating humidity range 5100% relative humidity including condensation Start-up time <5s Speed of response (t ) < 5s 90 Fast response time Speed of recovery < 5s CAN bus interface 500 kbit/s (ISO11898-2) PWM output (optional) Low power consumption 70 mA (typical) ESD and EMC protection Long-term stability and reliability Operating temperature range 40C to 90C Operating pressure range 0.5 1.2 bar (absolute) ams Datasheet Page 1 v1-00 2015-Apr-01 Document FeedbackH L S - 4 40P Ge ne r a l De s c ri p t i o n Benefits Features Safety integrity level and explosion Designed for SIL2 (IEC 61508) and ATEX 100a zone 2 proof IP6K7 and IP6K9K qualified with expected lifetime of 10 Long lifetime years Applications Detection of hydrogen gas leaks in fuel cell systems and other in-process applications. Block Diagram The functional blocks of this device for reference are shown below: Figure 2: HLS-440P Block Diagram LDO Voltage Regulation EMC Filter Protection Overvoltage, reverse polarity Power Supply Timer Controller Watchdog Output Switch Connector Heater Switch Resistor H2-Sensor Page 2 ams Datasheet Document Feedback v1-00 2015-Apr-01