AnsweredAssumed Answered

BF537 Core volatge and frequency relationship

Question asked by tneagoe on Sep 26, 2011
Latest reply on Sep 27, 2011 by Andreas

Hello there, one of my customers is using a ADSP-BF537KBCZ-6AV, commercial processor runninig at 600MHz.

He uses this processor at exactely 600MHz. Recently he noticed that some of the parts are failing to execute the code.

As you know there is a corelation between the core voltage and clock frequency. Core voltage suppose to be 1.3V

in order to allow the processor to run correctly at 600MHz.

Core voltage and frequency are controlled by VR_CTL register. Apparently all BF devices come pre-programmed

with a Vcore of 1.2V (-5%/+10%). This would explain why some of them show 1.2V and others 1.3V Vcore.

Therefore some run OK and some don't. For instance on a device that fails, if I force the VR_CTL to generate a 1.3V Vcore,

the processor behaves well. Strange.

Question: For 600MHz speed grade processors shoudn't the VR_CTL be preprogrammed at 1.3V?

If they all come pre-programmed with Vcore=1.2V (regardless of speed grade) should myself in the boot routine

set the VR_CTL to generate 1.3V?

 

Please advise,

 

Teodor Neagoe

Sr. FAE Arrow Electronics

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