nRF9160 COEX2 pin 100k pull-down

Question

Hi, 
 is the 100k pull-down on the COEX2 pin required as stated in the product specification ? I don't see it being followed anywhere (reference circuitry, nRF9160 DK schematic, Thingy:91 schematic, etc.) 
 Best regards, 
 Lukas

Sigurd · Accepted Answer

Sigurd said: It might be enough that the BLE chip uses its internal pull-down for this (13k ohm on nRF52x). In that case, an external resistor might not be needed…. I will double check this with the HW engineers. 
 The answer to this is: 
 Functionality wise, no extra pulldown expected needed then, but current leakage wise, the larger extra pulldown causes less current leak in modem active mode, when modem drives the pin high (= indicating no-GRANT). Whether this is a critical difference, may be customer use case dependent.

nRF9160 COEX2 pin 100k pull-down

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