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

    FRAM FM25CL64b non-responsive

    santosh_1948971

      Hello, 

         

      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.

         

       

         

      Thanks

        • 1. Re: FRAM FM25CL64b non-responsive
          gsns

          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?

             

          Thanks,

             

          Krishna.