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More on x51v backup capacitor problem
A while ago I replaced my X51v's backup capacitor (with a rechargeable lithium cell). It has been fine for several months but recently the time has once again been resetting while swapping batteries.
This evening I've taken the Ax apart to make some measurements; The results are both interesting and worrying.
First I removed the lithium cell. A few quick tests revealed it to be OK and holding a charge.
Then I measured the current required by the standby circuit, using an external 2.8v supply. It is drawing 2.7mA which is far too much for a standby circuit and enough to effect the battery life.
[There was another Ax owner asking if the backup cap could effect battery life in my 'replacing the backup cap' thread].
I gave the whole board a thorough clean with a high quality PCB cleaner / rinse agent (safewash2000) dried it with an air blast and 20 minutes in a temperature controlled oven. Yet it was still drawing 2.7mA through standby cell.
It would appear that something on my board (and many others) has begun to draw excessive current...
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Bill
Last edited by Bill_Todd : 03-16-08 at 07:28 PM.
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