Other Parts Discussed in Thread: CDCEL925,
The CDCE(L)9x datasheet says up to 4 devices can be connected onto the same I2C bus. That's fine if all 4 have unique I2C addr.
We're planning on using a CDCE925 (3V3 CLK O/P) and CDCEL925 (1V8 CLK O/P) on the same I2C bus.
The datasheet says the default I2C addr for the CDCE(L)925 is 1100100b. This means both devices have the same I2C addr, which means the Microcontroller (I2C bus master) won't be able to individually configure them.
The datasheet says the I2C addr can be changed by writing to a internal register in the EEPROM - but I can't because both them will be changed at the same time - thus a catch 22 situation.
I've also read that if the VDDOUT pin is held low (GND) the address will change to 1100100b? But this won't help me as this is the same as the default I2C addr anyway.
Otherwise I have to pre-programme this chips before I solder them to the board?
I presume the internal EEPROM is non-volatile, ie I only have to set the addr once and it will remember it for ever more. Otherwise I have to do this exercise each time the board is powered up.
Back ground info
CDCEL913: Default Address Bits - Clock & timing forum - Clock & timing - TI E2E support forums