ESD and Transient protection circuit- ISO 7637-3 and ISO 10605

[lajitha]

Hello ST team,

 

  We are currently developing and ECU for tractor. The ECU have many Digital inout and outputs to interface with sensors and other subsytems of the tractor. For the GPIO we have identified the ESDALY device suitable, since it conforms to the ISO standards for ESD and transients ISO 7637-3 and ISO 10605. We are planning to use ESDA5V3LY for our digital input and output circuits in the ECU as the operational  voltage is 5V. Based on that we have designed the circuit for DI and DO and we did LTSpice simulation of the circuit too and found that results seems ok. Kindly help us in finalising the circuits before proceeding with PCB design, as there are very minimal reference circuits available. The circuits are attached for reference. Please reply.

[FGUIT]

Hello

ESDALY is a good choice. Since the operating voltage is 5V, ESDA6V1LY should be used, as Vrm = 5.25V (for ESDA5V3LY, Vrm = 3V).

If you have more than 2 lines to protect that are close to each other, you can also use:

• ESDA6V1-5SC6Y, 5 lines, automotive grade, compliant with ISO 7637-3 and ISO 10605
• ESDA6V1SC6Y, 4 lines, automotive grade, compliant with ISO 7637-3 and ISO 10605

You can find all automotive grade ESD protection HERE. 

Best regards.

Fabrice.

[FGUIT]

If needed, an application note on PCB layout to maximize ESD protection efficiency.

Fabrice.

[lajitha]

Thanks Fabrice. But for  ESDA6V1LY, clamping voltage is 16V right? Hope we can limit the peak current by means of resistor and thereby a lower clamping voltage.

Also we hope that the other components such as RC filter, line driver, schmitt buffers included as part of the signal conditioning circuit in the block diagram attached  are okay.

 

If you have any refernce design for the ESD and transient protection for automotive/ generic GPIOs please share.

 

Regards

Lajitha