Re: Block a load supplied by an LDO

On Wed, 04 Jun 2008 18:57:39 GMT, Hammy <spamme@xxxxxxxxxxx> wrote:

On Tue, 03 Jun 2008 16:56:44 -0500, John Fields
<jfields@xxxxxxxxxxxxxxxxxxxxx> wrote:



Sample the input voltage to the regulator and use a comparator to hold
a P-channel MOSFET OFF until VIN has been stable long enough for you
to know that the output of the regulator is where it's supposed to be.

View in Courier:

PCH
VIN>--+-----+---+----+---[LDO]----S D---+
| | | | | G |
[Rt] [R1] | [R] | | |
| | | | | | |
+-----|--|-\ | | | [LOAD]
| | | >--+-----|--------+ |
| +--|+/ | |
| | | | |
[Ct] [R2] | | |
| | | | |
GND>--+-----+---+----------+--------------+

BTW, what are the LDO's input and output voltages?

JF

Thanks John worked like a charm!

---
:-)

JF
.

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