I am having a problem with a regulator and 12F675 both failing.

The regulator is a ZMR50H (Zetex) regulator SOT23 with 5V @ max 50mA O/P for
up to 25V I/P, this device has a low quiescent current.

The PIC is a 12F675 with an LM431 voltage reference (2.495V) for Vref, LED's
on 3 O/P's, MCLR is a digital input and the other pin is a analogue input.
The current consumption is around 17mA when operating.

With 25V I/P to the regulator and a resistive load I have no problems.  When
the PIC circuit is connected it blows (and the regulator) after being
switched on a few times.  It is not possible to tell which goes first but I
believe it is the regulator follwed by the PIC.

I have measured the current into the PIC on the +ve and 0V lines with a 10R
resistor and I find large current spikes, seen on a scope, of up to 800mA at
power up.  If the 10R resistor is in circuit the PIC and regulator survive.

I have tried modifying the CONFIG with WDTE and BODEN but this makes no
differance.  Has anyone else seen this problem and if so can it be fixed in
software or is it a Microchip silicon problem?

Regards

Ian
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