EYSHSNZWZ saadc value differ from the value of nrf52DK with same code

[nrfcho]

Hi i tested the code with nrf52DK with same code getting 3 analog value from AIN1, AIN2, AIN3 and it worked fine.

But when I use EYSHSNZWZ for my pcb, ADC value was just 20~38 which should be around 500(for around 1.5V). (i checked the pin mapping)

(I checked that the voltage of AIN1, AIN2, AIN3 with multimeter and it was correct voltages)

but the adc value shown is just 20~38 and does not change if I change the voltage to AIN1,AIN2,AIN3...

I followed the guideline below.

#define NRF_SDH_CLOCK_LF_SRC 0

#define NRF_SDH_CLOCK_LF_RC_CTIV 16

#define NRF_SDH_CLOCK_LF_RC_TEMP_CTIV 2

#define NRF_SDH_CLOCK_LF_XTAL_ACCURACY 0

Can someone help me?

It's so weird that it works fine with nrf52DK....

[haakonsh]

What's the SAADC configuration? 

Can you short AIN1 to VDD and read out the sampled value? 

[nrfcho]

its not changing its still same value around 40..

[nrfcho]

void saadc_init(void)
{
ret_code_t err_code;
nrf_saadc_channel_config_t channel_0_config =
NRF_DRV_SAADC_DEFAULT_CHANNEL_CONFIG_SE(NRF_SAADC_INPUT_AIN1);
nrf_saadc_channel_config_t channel_1_config =
NRF_DRV_SAADC_DEFAULT_CHANNEL_CONFIG_SE(NRF_SAADC_INPUT_AIN2);
nrf_saadc_channel_config_t channel_2_config =
NRF_DRV_SAADC_DEFAULT_CHANNEL_CONFIG_SE(NRF_SAADC_INPUT_AIN3);
err_code = nrf_drv_saadc_init(NULL, saadc_callback);
APP_ERROR_CHECK(err_code);

err_code = nrf_drv_saadc_channel_init(0, &channel_0_config);
APP_ERROR_CHECK(err_code);

err_code = nrf_drv_saadc_channel_init(1, &channel_1_config);
APP_ERROR_CHECK(err_code);

err_code = nrf_drv_saadc_channel_init(2, &channel_2_config);
APP_ERROR_CHECK(err_code);

err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[0], SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);

err_code = nrf_drv_saadc_buffer_convert(m_buffer_pool[1], SAMPLES_IN_BUFFER);
APP_ERROR_CHECK(err_code);

}

this is my code for saadc_init

[haakonsh]

I suggest you re-check your pin mappings.

nrfcho said:

its not changing its still same value around 40..

 And if you connect AIN1 to VDD is the value still ~40?