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tlv320aic23b

Started by Micah Caudle October 18, 2004

Has anybody ever used the Texas Instruments
tlv320aic23b codec? Has anybody ever had a problem
with that chip being easily susceptible to static
discharges ocuring anywhere near it? I'm trying to use
it in a product and we are trying to get it to pass
the part of the CE test where you hit the product case
with a 10KV static discharge without interrupting
normal operation. Real often, this static discharge
causes the codec to output nasty harmonics, sometimes
on both line outs and sometimes only on one of the two
line outs. The sensitive pins seem to be XTI and XTO
because any disturbance in the crystal's waveform
there causes the same problem. I was just wondering if
anybody knew if this codec has any history of this
kind of problem. I'm starting to think it may be a
problem internal to the chip as opposed to a pcb
layout or circuit design problem. -Micah

__________________________________




Micah-

XTAL inputs are high-impedance and are always sensitive to static and other
nearby
energy sources.

What about using oscillator input? Or a CLKOUT line from the DSP?

-Jeff

Micah Caudle wrote:
>
> Has anybody ever used the Texas Instruments
> tlv320aic23b codec? Has anybody ever had a problem
> with that chip being easily susceptible to static
> discharges ocuring anywhere near it? I'm trying to use
> it in a product and we are trying to get it to pass
> the part of the CE test where you hit the product case
> with a 10KV static discharge without interrupting
> normal operation. Real often, this static discharge
> causes the codec to output nasty harmonics, sometimes
> on both line outs and sometimes only on one of the two
> line outs. The sensitive pins seem to be XTI and XTO
> because any disturbance in the crystal's waveform
> there causes the same problem. I was just wondering if
> anybody knew if this codec has any history of this
> kind of problem. I'm starting to think it may be a
> problem internal to the chip as opposed to a pcb
> layout or circuit design problem. -Micah