I wondered why nobody had mentioned something like this before. This should
work fine.
The nice thing about this method is you can probably use cheepo alkaline
batteries that are available anywhere. The regulator will take care of the
battery voltage drop over time.
I work with surface mount electronics all the time but I haven't been brave
enough to open up my OM-1 to see where this circuit could go...
The link to the regulator data sheet is
http://www.linear-tech.com/cgi-bin/database?function=elementinhtml&filename=DataSheet.html&name=DataSheet&num=594
Or just go to http://www.linear-tech.com and search for 1761
--
Jim
>For anyone interested in a battery replacement for a 1.35V mercury
>cell, I just tested one of our (Linear Technology) LDO regulators (low
>drop out regulator) and it seems to work. The part is the LT1761. (see
>www.lineartech.com for the data sheet). For an input I used a 1.5V
>source (1.5-1.55V is typical for silver oxide battery) and the
>regulated output was 1.35V. The part draws 20uA of quiescent current
>and easily handled 300uA load, which is probably more than enough for
>an OM-1. The part requires two external adjust resistors to set the
>output level and an output bypass cap of 1uF (see page 12 of the
>datasheet for the circuit). I used a 1.5Meg and a 193K resistor to set
>the output to 1.35V. The part is in a tiny SOT-23 package. The circuit
>can be turned off by putting it in series with the off switch or by
>using an optional shutdown pin. I have half a dozen parts if anyone
>would like one to try for them self. Requires good soldering skill.
>
>Wayne
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