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Is there a standard that propose voltage/current thresholds for GPIO in automotive ECUs. Something that would define ViH, ViL, Iil, IiH, etc for 12V or 24V networks.

I have good intuition of what is needed by working with different types of controllers, but I'd like to find something more rigorous to back up a design. The best I found is IEC-61131-2 which defines these levels for PLC.

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  • \$\begingroup\$ This question is unclear, automotive MCU's/PLC's GPIO's usually top out at 5V. If your using a communication protocol like CAN, then the levels are defined by the communication standard. \$\endgroup\$ – Voltage Spike Aug 6 '19 at 18:04
  • \$\begingroup\$ Hmm as far as I know, automotive ECUs usually have IOs referenced to the 12V/24V batteries, driven with either low side or high side drivers. \$\endgroup\$ – Pier-Yves Lessard Aug 6 '19 at 18:05
  • \$\begingroup\$ Name one automotive ECU that has GPIO's that are 12V tolerant. \$\endgroup\$ – Voltage Spike Aug 6 '19 at 18:06
  • \$\begingroup\$ Most of them? Look at Parker CM410. I won't name all brands. My question refer to a standard that defines voltage levels that goes up to 60V, I recommend you take the time to look at it \$\endgroup\$ – Pier-Yves Lessard Aug 6 '19 at 18:17
  • \$\begingroup\$ CM0410, can't edit my previous comment \$\endgroup\$ – Pier-Yves Lessard Aug 6 '19 at 18:23
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The SAE SENT protocol defines an interface standard for automotive sensors.

More here: https://www.sae.org/standards/content/j2716_201001/

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  • \$\begingroup\$ Interesting, thank you. SENT is more of a communication protocol rather than a GPIO standard. That is not exactly what I am looking for, though. \$\endgroup\$ – Pier-Yves Lessard Aug 6 '19 at 18:22
  • \$\begingroup\$ Automotive platforms are a hodgepodge of protocols and signaling methods, tailored for their use. I think that focusing on an attempt to capture a ‘standard’ for something as low-level as GPIO is not the right approach. \$\endgroup\$ – hacktastical Aug 6 '19 at 19:01
  • \$\begingroup\$ You may be right. Honestly, I have the feeling I would have already found such document if it existed. \$\endgroup\$ – Pier-Yves Lessard Aug 6 '19 at 19:06
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    \$\begingroup\$ There is a general trend in automotive to try to reduce wiring to save weight and cost. At the same time, there is pressure to accommodate high-rate data from sources like cameras. Then there is the trend to integrate infotainment systems with the platform (which is fraught with security issues - see FCA’s fiasco with Rockford Fosgate.) These trends all work against using GPIO as a basic approach, except at the very lowest level. Even then, there is an assumed adaptation layer between the MCU and what it interfaces with. SENT is an initative to harmonize sensors but it’s only a small piece. \$\endgroup\$ – hacktastical Aug 6 '19 at 19:47
  • \$\begingroup\$ I partially agree. There is also a trend to go towards more safe desings and I'm talking about ISO-26262 here. Critical mechanical assemblies require highest reliability for safety and often an IO feedback is cheaper and more simple (thus less failure probabilities) than some sort of transceiver. I don't think it is meant to disappear. \$\endgroup\$ – Pier-Yves Lessard Aug 6 '19 at 20:32

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