I need 1.1 and 1.2 volt rails from available 1.5. Rather than adding yet another regulator to stock, I figured I'd just do it.
The opamp will actually be a dual MC33072, and the fet a dual Zetex SO8.
ftp://jjlarkin.lmi.net/TEM2_LDO.jpg
Maybe R1 could be a little smaller.
John
Version 4 SHEET 1 880 680 WIRE 144 -176 32 -176 WIRE 608 -176 416 -176 WIRE 144 -144 144 -176 WIRE 608 -112 608 -176 WIRE 416 -48 416 -176 WIRE 144 -32 144 -64 WIRE 32 0 32 -176 WIRE 608 0 608 -32 WIRE 0 16 -32 16 WIRE 144 32 64 32 WIRE 192 32 144 32 WIRE 224 32 192 32 WIRE 368 32 304 32 WIRE -144 48 -208 48 WIRE 0 48 -144 48 WIRE 32 80 32 64 WIRE -208 96 -208 48 WIRE -32 144 -32 16 WIRE 80 144 -32 144 WIRE 144 144 144 96 WIRE 144 144 80 144 WIRE 224 144 144 144 WIRE 416 144 416 48 WIRE 416 144 304 144 WIRE 512 144 416 144 WIRE 608 144 512 144 WIRE 416 176 416 144 WIRE 512 176 512 144 WIRE 608 176 608 144 WIRE -208 208 -208 176 WIRE 512 272 512 240 WIRE 416 288 416 240 WIRE 608 288 608 256 WIRE 512 384 512 352 FLAG 144 -32 0 FLAG 32 80 0 FLAG -208 208 0 FLAG 416 288 0 FLAG 608 0 0 FLAG 512 384 0 FLAG 608 288 0 FLAG 608 144 OUT FLAG -144 48 IN FLAG 192 32 AMP FLAG 80 144 FB SYMBOL cap 400 176 R0 SYMATTR InstName C1 SYMATTR Value 3µ SYMBOL cap 496 176 R0 SYMATTR InstName C2 SYMATTR Value 10µ SYMBOL cap 128 32 R0 WINDOW 0 49 42 Left 0 WINDOW 3 50 73 Left 0 SYMATTR InstName C3 SYMATTR Value 1n SYMBOL Opamps\\LT1492 32 -32 R0 WINDOW 0 -76 -33 Left 0 WINDOW 3 -104 3 Left 0 SYMATTR InstName U1 SYMBOL res 320 16 R90 WINDOW 0 -45 59 VBottom 0 WINDOW 3 -36 60 VTop 0 SYMATTR InstName R1 SYMATTR Value 100 SYMBOL res 320 128 R90 WINDOW 0 72 52 VBottom 0 WINDOW 3 78 52 VTop 0 SYMATTR InstName R2 SYMATTR Value 10K SYMBOL nmos 368 -48 R0 SYMATTR InstName M1 SYMATTR Value FDC637AN SYMBOL voltage 608 -128 R0 WINDOW 0 55 39 Left 0 WINDOW 3 53 82 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 1.5 SYMBOL voltage -208 80 R0 WINDOW 3 -161 182 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR Value PULSE(1.1 1.15 100u 0 0 200u) SYMATTR InstName V2 SYMBOL voltage 144 -160 R0 WINDOW 0 61 23 Left 0 WINDOW 3 60 60 Left 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value 12 SYMBOL res 592 160 R0 WINDOW 0 58 43 Left 0 WINDOW 3 64 76 Left 0 SYMATTR InstName R3 SYMATTR Value 1 SYMBOL res 496 256 R0 WINDOW 0 47 62 Left 0 WINDOW 3 41 98 Left 0 SYMATTR InstName R4 SYMATTR Value 0.05 TEXT 88 288 Left 0 !.tran 0.001 TEXT -456 -136 Left 0 ;TEM2 LDO REGULATORS TEXT -416 -88 Left 0 ;JL Sep 12 2011