Hi ADI team,
I’m integrating the DS2480B+T&R 1-Wire line driver in my design and, following the datasheet recommendations, I’ve placed a DS9503P+ ESD-protection diode on the 1-Wire bus.
The DS9503 datasheet states that “the end pins of the internal resistor should face the side that presents the ESD threat.” However, Figure 4 (Typical Application) shows two additional series resistors (“1” and “2”) between the diode and the ESD-threat side. This seems to contradict the earlier guidance, because it appears the diode is no longer the first component struck by an ESD event.
My implementation (see attached image) also includes an RC filter between the DS2480B and the DS9503P+. Before I commit the PCB, could you please confirm:
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Whether the extra series resistors in Figure 4 are mandatory or optional for proper ESD protection.
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The correct orientation of the DS9503P+ internal resistor pins relative to the ESD-threat side when those external series resistors are present.
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Any impact the RC filter might have on the timing or integrity of the 1-Wire signals in this configuration.
Thank you for your guidance.
Best regards,
Priyanshu
