GPIO PIN output max Voltage of XMC1302

[Rex_xu]

Hi All,

Does anyone knows the max voltage of XMC1302 GPIO can output?

In my PCB, I connected a Nmos Gate to XMC GPIO, Nmos Source to GND, Nmos Drain to another IC's Chip enable pin which has 4V (active high, pull this pin to logic low can disable the chip).

I want to control the IC's enable/disable. But when I pull up the GPIO, only about 0.9V I got. Can't reach the GS threshold voltage. (Min 1.0V, typ 1.75V)

Thanks.

[Owen_Su]

Hi, @Rex_xu ,

    You can find the absolute maximum rating parameters in pages 34, hope this can help you.

Regards,

Owen_Su

[Rex_xu]

Thank you Owen, but that was the Vin voltage I think?

[Owen_Su]

Hi, @Rex_xu ,

    As my understanding, Vout of GPIO is not higher than VDD, and the absolute maximum parameters define the values which could damage the product. 

    I wonder if I can know your GPIO output config, as your mention above, I think that your Vgs is not conducting, it is possible that your output mode is set to 'strong', you can try to set the output mode to 'resistance pull up'. Hope this can help you.

Regards,

Owen_Su

[Rex_xu]

Hi Owen

below is part of my code:

#define CE P2_4

// GPIO pin(LED1/LED2/CE) configuration
XMC_GPIO_CONFIG_t config =
{
.mode = XMC_GPIO_MODE_OUTPUT_PUSH_PULL,
.output_level = XMC_GPIO_OUTPUT_LEVEL_HIGH,
};

void CE_enable(void)
{
XMC_GPIO_Init(CE, &config);
XMC_GPIO_SetOutputLow(CE); 
}

[Owen_Su · Accepted solution]

Hi, @Rex_xu ,

    You can find in the data sheet that the port 2_4 is not suitable for the  function of output, and different function need to match different mode.

    I use a multimeter to test P0_0, when I set output low , the output voltage is about 1.738V, and the output voltage is about 4.94V when I set output high. You can change another port to test your platform. Hope this can help you.

Regards,

Owen_Su

[Rex_xu]

Hi Owen

Thank you very much. I find it from table 6 PIN mapping. Voltage is 3.29V when I set output high, and 0 when I set low. P0_0 is floating now.

Rex_Xu

[Owen_Su]

Hi, @Rex_xu 

    I use exactly the same codes with you, maybe you can check if you can light the LED correctly, or check other basic functions of the board to make sure there is nothing went wrong with the hardware. Hope this can help you.

Regards,

Owen_Su

[Rex_xu]

Hi Owen

I did the test on my PCB, cut the line and fly it to P0.2. It works fine, now I can controll the NMOS on/off, thanks again.

Rex_xu