One of my customers is using the AD5111 digital potenziometer.
He has an issue with writing to his egisters
Their tining is according to the figure 3 in the data sheet
The CS is tied to "low" by pull down. During this cycle the CLK is in HIGH
The writing cycle is failed whther they start the U/D# pin from "HIGH" as follows: HIGH-LOW-HIGH-LOW - then the EEPROM programm is not succeeds.
Using the following U/D# cycle the EEPROM programm is performed successfully: LOW-HIGH-LOW .
I can't see any limitations for it in data sheet.
Do you have any idea why during the HIGH-LOW-HIGH-LOW cycle the writing to the eeprom is failed?