1 Reply Latest reply on Jun 22, 2017 11:34 PM by krishnag_71

    FRAM FM25CL64b non-responsive



      I have a FM25CL64B FRAM chip on my board - the FRAM chip does not respond to SPI at all. Vdd is at 3.305V and both WP and HOLD are tied to Vcc. We replaced a standard flash chip to try out this part - the controller to fram chip connections are good. Controller outputs to FRAM are all good - CS, SI and SCK all look good - except SO is held high. I have tried multiple SPI modes, inserted multiple ms delay before accessing the device, but nothing helped. 


      Would really appreciate any assistance in root causing this issue.





        • 1. Re: FRAM FM25CL64b non-responsive

          Hi Santosh,


          Sincere apologies for the delay.


          Please clarify the below queries:


          1.if your following tVR and tVF spec mentioned in the datasheet?


           2.How many parts (FRAM devices)are failing ?


          3. which flash device you are using ? what are the operations you are trying to perform?