2182853_en-US

MIMXRT1052CVL5B on-chip LDO short-circuits during use

During an occasional power-up, I found that the RT1052 could not be activated and the REQ signal was not emitted. After measurement, I found that the on-chip LDO_SNVS and LDO_1P1 are short-circuited, resulting in the inability to activate the PMU module of the RT1052, but the reason is unknown, and the attached is part of the peripheral circuitry of the RT1052, is there any irrationality?

回复： MIMXRT1052CVL5B在使用过程中出现的片内LDO短路现象

Addendum: The short circuit part of the measurement is measured at both ends of C337 and both ends of C339 in the attachment, and the resistance to ground is 0~2Ω.

And after referring to other RT1052 schematic designs, I found that the Pswitch circuit is slightly different from other designs. In this design, a U141 chip is added to increase the delay time by 240ms, and I am not sure if it will affect the on-chip DCDC enable.