AD9262 ADC output stuck at constant value

Hi, Roli .

Moving this thread to the High-Speed ADCs forum. JAlipio will look into this and get back to you.

Regards,
Jo

Hi Roli 

Thanks for using AD9262.

This behavior may be due to incomplete initialization or internal blocks not resetting properly, especially since the RST pin is tied to ground and cannot be used for a hardware reset.

To address this, consider the following steps:

• Software Reset via SPI, write to Register 0x00, Bit 2 & 5 to trigger a soft reset.
• Clock Stability During Power-Up. Ensure a valid and stable clock signal is present during power-up. An unstable or missing clock can cause the ADC to lock up or output constant values.
• Check and Reset Internal Blocks:
  • SRC (Sample Rate Converter): Confirm it is properly initialized and reset if used.
  • PLL (Phase-Locked Loop): Verify lock status and reset if necessary.
  • ORx (Overrange Detection): Check for false overrange conditions that may affect output behavior.
• Power Down and Reinitialize via SPI. Use the power-down command, write to Register 0x08 to disable the ADC. Re-enable and reconfigure all necessary registers after reset.

Hi JAlipio

Thanks for your answers.
Softreset only does not solve the problem. Power down (and reinitialize) worked, but not as described in Datasheet with Channel Index(register 0x05) set to 0. It only works if this register 0x05 ist set to 3.

We now check if Overrange Detection is configured correctly.

Best Regards

Roli