gpio output voltage control

[TTN]

Hi,

I want control my gpio P0.06 to enable mcp16251, which is a regulator provide power to the nrf52832,

when i trying to control the mcp16251, i found that the gpio can't enable the mcp16251, the reason is the gpio output voltage is 1.93, not able to enable the mcp16251.

the switch condition shows in the below picture.

then i find i strange that my Vouts to nrf52832 vdd is 2.83v, but the gpio output is not the value VDD-0.4=2.44.

the P0.06 output voltage value is 1.93v,

my custom board power is on the DC/DC mode, seems the power mode will influence the gpio output voltage.

any suggestion help me to drive the gpio pin in the vlotage VDD-0.4.

or can i choose either LDO nor DC/DC to power to control the nrf52832?

[Kenneth]

The value you refer to state that is you can sink up to 3mA from the GPIO. Do you know the sink current from P0.06?

Is it possible that P0.06 is configured for other purpose in your project? For instance it typically may be used for debugging (UART) in the SDK projects.

[hmolesworth]

Try increasing the high level output drive current on that pin, assuming the pin is not already in use elsewhere:

   nrf_gpio_cfg(6,                       // P0.6
                NRF_GPIO_PIN_DIR_OUTPUT,
                NRF_GPIO_PIN_INPUT_DISCONNECT,
                NRF_GPIO_PIN_NOPULL,
                NRF_GPIO_PIN_S0H1,       // Require High Drive high level
                NRF_GPIO_PIN_NOSENSE);

[TTN]

Hi, thanks for reply.

I have add the gpio_cfg in my project.

nrf_gpio_cfg_output(6);
nrf_gpio_cfg(6, // P0.6
NRF_GPIO_PIN_DIR_OUTPUT,
NRF_GPIO_PIN_INPUT_DISCONNECT,
NRF_GPIO_PIN_NOPULL,
NRF_GPIO_PIN_S0H1, // Require High Drive high level
NRF_GPIO_PIN_NOSENSE);
nrf_gpio_pin_set(6);

But the voltage value still at 1.94v , before or after the code been added.

I'm still curious why the Voh's min. value not  VDD-0.4, when my input vdd is 2.8v.

[hmolesworth]

Is the nRF52832 you are using on the nRF52 dev board by any chance? If so the SAM3U2 may be holding P0.06 which is connected as the Rx line (as Kenneth indicated). If this is a custom board you could try paralleling another high-drive pin, but as the Enable Pin only requires 1mA (which is a lot) I agree you should already be within specification. In the code above nrf_gpio_cfg_output(6); is now redundant of course