Flash Write Fail in CY8C201x0 Devices - KBA85520

Version: *A

 

Question:

Why does the “write configuration to flash” command fail for CY8C201x0 devices?

 

Answer:

In some devices, flash write fails at operating voltages below 3.0 V. The primary reason is that the CPU clock frequency decreases at lower operating voltages. As a result, the “flash write” routine takes longer and a watchdog reset occurs before the routine is completed. This issue typically occurs on devices that have relatively fast ILO (even though the ILO is within the datasheet specifications).

Workaround: Because watchdog reset triggers when the sleep timer expires three times, reduce the sleep timer frequency (which is configurable over I2C) to 8 Hz or below (if Vdd < 3.0V) before you store the configuration to flash.