Power chip for a CryBaby Classic with Fasel

[52 Bill]

I have seen 2 of these already. The new surface mount board has some sort of voltage regulator or management chip at U4, that goes open and kills all voltage to the circuit.

The only marking is G121. It's a 5 pin ssop-5 package.
No response from Dunlop so far for replacement parts or for identity.

Bypassing will fix problem.
Anybody seen this before or know what the chip is?

[x-pro]

may be http://www.bdtic.com/ST/STMPS2121.html

[x-pro]

Either that. And it has 1/2 of the power supply formed on it.
http://pdf-html.ic37.com/pdf_file_A/..._datasheet.pdf

[Mark Hammer]

Are there individual transistors visible on the board?

[52 Bill]

x-pro: Thank you for the lead on the STMPS2121. I will look at the data sheet and see if it will work in this circuit.

Mr. Hammer: Yes the circuit is the usual Cry Baby circuit, with the added power supply circuit. There are 2 or 3 discrete transistors, all the usual caps and resistors plus the Fasel coil.