BG95 USIM_VDD, can I keep it powered to 1.8v using an LDO at all times?

IoT Modules LPWA Module
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Currently, my BG95 module works. It can power the sim card and send/receive messages with one sim connector. I want to use TXS02326A to multiplex it so I can switch between two sim cards. The issue is the BG95 drives the USIM_VDD pin. It briefly powers up to 1.8v and turns off if a sim isn’t detected. So I have several questions regarding the how the USIM_VDD pin works.

  1. What triggers the USIM_VDD pin and how do I keep it on?
  2. Can I connect USIM_VDD to the mux chip (TXS02326A) 1.8v LDO and power on at all times? Is it safe to power the USIM_VDD to 1.8v at all times?
  3. Or can I connect the USIM_VDD pin from the BG95 directly to both sim connectors and let the mux handle only the signals (IO/DATA, CLK, RST)?

Please let me know what I can safely do to mux between two sims.

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Here’s the diagram, but the microprocessor (BG95) has a USIM_VDD that powers the sim. What should I do with the USIM_VDD? And how do I prevent feedback coming from the sim if one sim will be powered and the other one will be switched on?

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  1. What triggers the USIM_VDD pin and how do I keep it on?
    Reply:The module will automatically output when turned on, and if normal communication is maintained. Once communication is abnormal, the module will turn off the USIM.VDD power output.
    To turn on the power, you can use AT+CFUN=0 and then AT+CFUN=1,
  2. Can I connect USIM_VDD to the mux chip (TXS02326A) 1.8v LDO and power on at all times? Is it safe to power the USIM_VDD to 1.8v at all times?
    Reply:Cannot follow the design you described
  3. Or can I connect the USIM_VDD pin from the BG95 directly to both sim connectors and let the mux handle only the signals (IO/DATA, CLK, RST)?
    Reply：It is generally not recommended to follow the design you described.

Suggest referring to the following diagram：

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