Can the SF32LB-MOD-1 be powered with 3.3V?

Troubleshooting
1

I designed a circuit using the LC-OPEN-SF32LB52-MOD-N16R8 module. Pin 27 of the module is originally designed for 3.3V power supply, but I couldn’t download the program. I increased this voltage to about 3.7V to 4V and it worked. However, the datasheet of the SF32LB525UC clearly states that 3.3V can be used to power pin 24 VCC of the chip. Moreover, the official SF32LB52-DevKit-LCD development board also has a 3.3V power supply path (but it is isolated by a default unpopulated 0-ohm resistor). So, can this module use a 3.3V supply, or must it be greater than 3.7V to work?

3

I made 10 boards and tried 3 of them, but none could download the program. However, switching to 3.7v works, but switching back to 3.3v still doesn’t work.

4

Initial power-on must be greater than 3.7V.

5

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6

Does it mean that 3.7V must be used to ‘activate’ the chip, after which the voltage can be lowered to 3.2V? Can it be understood that way?