TMS320F2812A: temperature at the surface at 150MHz

Hello,

we are using the F2812 A  in  MicroStar BGA package  (Typ GHH)
with 150MHz internal clock and all peripheral modules (except McBSP)
activated.
The CORE voltage is 1.9V.

After about 15 minutes we measure a surface temperatur of 60�C at room
temperature (23�C).
We think that this is too much ! (opperating temperature of the
DSP: -40�C...85�C)

What temperatures have your DSPs ?
Which are your experiences ?
What are common temperatures for such applications ?


Thanks for help,

Chris

In comp.dsp,
Christian Zipper <c.zipper.nospam@nospam.bebro.de> wrote:
>Hello,
>
>we are using the F2812 A  in  MicroStar BGA package  (Typ GHH)

Can't seem to find the F2812A on ti's website, F2812 only.

>with 150MHz internal clock and all peripheral modules (except McBSP)
>activated.
>The CORE voltage is 1.9V.
>
>After about 15 minutes we measure a surface temperatur of 60&#4294967295;C at room
>temperature (23&#4294967295;C).
>We think that this is too much ! (opperating temperature of the
>DSP: -40&#4294967295;C...85&#4294967295;C)
>
The -40 to +85 degrees specification is for ambient temperature only
so at 23 degrees you're pretty safe. See if you can find max case
temperature in the datasheet or calculate it from max junction,
junction-case thermal resistance, ambient temp and dissipated power.

But in any case, the maximum case temperature should be well above
the maximum allowed ambient, otherwise the device would not be
permitted to dissipate any power.

And check if there are any layout rules or thermal design guidelines
for your DSP. Measure the power consumption and compare it with the
datasheet values. You probably have nothing to worry about, but
checking can never hurt.

>What temperatures have your DSPs ?
>Which are your experiences ?
>What are common temperatures for such applications ?
>
These things depend very much on the application and the specific
DSP or CPU. But as a general rule you would expect high performance
CPU's to run hotter than low performance ones.

-- 
Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

When I left you, I was but the pupil.  Now, I am the master.
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