MC34708, Silicon Errata

[T_I]

We design our custom board based on MCIMX53-START-R.

DDR_Vref is generated in MC34708, But MC34708 have Silicon Errata. 

The contents of Silicon Errata as follows.(MC34708ER Rev. 5.0, 4/2012)

"Description:VREFDDR output should be 2% accurate over temp. At 85°C, the output accuracy of 

VREFDDR can go as high as 6.5%."

"Workaround:Use an external resistor divider to generate VREFDDR"

Would Freescale make a MCIMX53-START-R before this was informed of it?

Should I use an external resistor divider? Or May I use a MC34708 ?

[T_I]

Hello,

Thank you for your quick reply. I design it as you taught it.

Thanks,

[NitinSonar]

Hi,

Better to use divider circuit. Similar divider is used in iMX53 SABER design as well. Doing so will have flexibility to adjust VREFDDR and hence provide better stability. We have followed similar method for our custom board and works well.

Best Regards

Nitin Sonar