In connection with the concept of using the LH1262 (or similar) device,
I have two questions for the group members:
1. To implement the "regulation" suggested by raymonddf, applied to the
use of an LH1262 as proposed by mlitwack, would it be possible to feed
the output of the LH1262 (about 12 or 13 volts unloaded) to a resistor
in series with a string of 1n914 diodes (a shunt regulator) to obtain
the "target" 1.35V voltage (or close to it)? The Fairchild 1n914
datasheet indicates approximately 250 mV forward drop (at 25 deg C) in a
1n914 with 1.0 microamp forward bias; perhaps six 1n914 diodes in series
with a 10 megohm resistor would work?
2. Another poster (edbreya) suggested "you need to read... message
112514...then look at 96664..." If I log into the tekscopes yahoo group
site and do a "conversations" search on "112514" I can access the 112514
message, but if I attempt a similar search on "96664" I get nothing.
Can someone explain to me how I might get access to message 96664?
Mike N4MWP
On 12/04/2014 01:42 PM, raymonddf@... [TekScopes] wrote:
The photovoltaic MOSFET approach would work of course. Current is more
than enough but regulation is compulsary at >13 V open circuit. The
sampler diodes in reverse bias hardly allow any current through.
Raymond
Another possibility on the photovoltaic approach is Vishay's LH1262
photovoltaic MOSFET drivers. It has two photovoltaic generators in a
DIP or SOIC package. You can get a minimum of 2.6uA each (3.4uA to
6.9uA typ, depending on drive current), with an open circuit voltage
of about 13.5V.
Regulation would still be needed, obviously, probably by loading the
output and controlling the drive current as in the referenced
artcicle. Or maybe that's enough current for an ultra-low power
regulator.
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[Non-text portions of this message have been removed]
Mike Dinolfo