Version 4
SHEET 1 2868 680
WIRE 256 -96 96 -96
WIRE 512 -96 320 -96
WIRE 96 16 96 -96
WIRE 240 16 96 16
WIRE 512 16 512 -96
WIRE 512 16 320 16
WIRE 960 64 640 64
WIRE 1232 64 960 64
WIRE 1344 64 1312 64
WIRE 1536 64 1344 64
WIRE 960 96 960 64
WIRE -224 128 -896 128
WIRE -80 128 -144 128
WIRE 288 176 288 128
WIRE 1408 192 1408 160
WIRE 800 208 800 160
WIRE 1344 208 1344 64
WIRE 1376 208 1344 208
WIRE 1392 208 1376 208
WIRE 96 224 96 16
WIRE 256 224 96 224
WIRE 640 224 640 64
WIRE 768 224 640 224
WIRE 784 224 768 224
WIRE 1536 224 1536 64
WIRE 1536 224 1440 224
WIRE 1584 224 1536 224
WIRE 960 240 960 160
WIRE 960 240 832 240
WIRE 1024 240 960 240
WIRE 1184 240 1088 240
WIRE 1248 240 1184 240
WIRE 1376 240 1328 240
WIRE 1392 240 1376 240
WIRE 512 256 512 16
WIRE 512 256 400 256
WIRE 768 256 512 256
WIRE 784 256 768 256
WIRE -224 288 -448 288
WIRE -80 288 -80 128
WIRE -80 288 -144 288
WIRE 256 288 -80 288
WIRE -1040 320 -1040 256
WIRE -896 320 -896 128
WIRE 1184 320 1184 240
WIRE 96 368 96 224
WIRE -448 384 -448 288
WIRE -1040 480 -1040 400
WIRE -896 480 -896 400
WIRE -448 528 -448 464
WIRE 96 528 96 448
WIRE 288 528 288 336
WIRE 800 528 800 272
WIRE 1184 528 1184 384
WIRE 1408 528 1408 256
FLAG -448 528 0
FLAG -896 480 0
FLAG -1040 480 0
FLAG -1040 256 3.3V
FLAG 96 528 0
FLAG 288 128 3.3V
FLAG 288 528 0
FLAG 800 528 0
FLAG 800 160 3.3V
FLAG 1408 160 3.3V
FLAG 1408 528 0
FLAG 1184 528 0
SYMBOL voltage -448 368 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value EXP(0 50m 0 10n 0 500n)
SYMBOL voltage -896 304 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value EXP(0 800m 6u 10n 0 1.5u)
SYMBOL voltage -1040 304 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V3
SYMATTR Value 3.3
SYMBOL Opamps\\LTC6268 288 256 R0
SYMATTR InstName U2
SYMBOL res 80 352 R0
SYMATTR InstName R1
SYMATTR Value 270
SYMBOL res 336 0 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R2
SYMATTR Value 1.2k
SYMBOL cap 320 -112 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C1
SYMATTR Value 10p
SYMBOL res -128 272 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 1k
SYMBOL schottky 944 96 R0
SYMATTR InstName D1
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL schottky 1024 256 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D2
SYMATTR Value BAT54
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 1168 320 R0
SYMATTR InstName C2
SYMATTR Value 10n
SYMBOL res 1344 224 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R4
SYMATTR Value 1k
SYMBOL res 1328 48 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R5
SYMATTR Value 1k
SYMBOL Opamps\\LTC6254 800 240 R0
SYMATTR InstName U1
SYMBOL Opamps\\LTC6254 1408 224 R0
SYMATTR InstName U3
SYMBOL res -128 112 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R6
SYMATTR Value 1k
TEXT -480 552 Left 2 !.tran 10u
TEXT 208 592 Left 2 ;Gain = ~2.5
TEXT 200 624 Left 2 ;1.1Vin = 2.7Vout
TEXT 1568 280 Left 2 ;OUT