I have a trouble in using STM32F103RET6 MCU.
The problem is as follows.
My board has one STM32F103RET6 as a controller and uses SPI2, UART2, 4 channels of ADC and some GPIOs.
I downloaded the simple firmware using JLINK/SW mode.
The board worked well for some minitues and after sometime, looked as halted.
I doubt if MCU might be breakdown and so tested the resistance between VDD and GND using multitestet diode testing mode.
The resistance was measured as 50 or 200 or 19 in both direction.
But i found that after keeping the board as power off for several hours, that resistance was came back to the value of 412 in reverse direction and 1550 in forward direction.
I replaced with new chip but that phenomena was occured repeatedly.
I used LP5907MFX-2.8(2.8V/200mA LDO) as a power supply for MCU.
I cannot understand this phenomena.
Please help me to explain this phenomena.