* SPICE netlist
R1 IN N003 274K
MQ1 IN N001 N002 N002 BSH114
R2 IN N001 100K
D1 N002 N004 1N4148
C1 N004 N007 .1
MQ2 IN N006 N007 N007 Si7850DP
MQ3 N007 N012 0 0 Si7850DP
C2 N002 0 1
L1 N007 OUT 7.7
D2 0 N007 MBRS1100
R3 OUT N013 14K
R4 N013 0 1K
C3 OUT 0 270 Rser=10m
C4 N011 N013 33p
C5 N008 0 560p
R5 N005 N002 100K
C6 N010 N009 .01
XU1 N003 MP_01 MP_02 N002 N002 N005 0 N011 N013 N010 N008 0 N002 N002 N001 OUT N002 N002 N012 0 0 MP_03 MP_04 MP_05 N007 N007 N006 N004 LTC3810 ;pnba Ion)))Von)Vrng)Pgood)MODE/SYNC)Ith)FB)PLL/LPF)SS/TRACK)SGND)_SHDN)UVIN)NDRV)EXTVcc)INTVcc)DRVcc)BG)BGRTN)Sense-))))Sense+)SW)TG)Boost
R6 N014 N013 90.9K
C7 N011 N014 220p
R7 N009 0 10K
V1 IN 0 24
Rload OUT 0 3
.tran 750u startup

* LTspice schematic (.asc)
Version 4
SHEET 1 1344 1104
WIRE -128 -552 -352 -552
WIRE 144 -552 -128 -552
WIRE 256 -552 144 -552
WIRE 368 -552 256 -552
WIRE -352 -536 -352 -552
WIRE -128 -536 -128 -552
WIRE 368 -536 368 -552
WIRE 144 -520 144 -552
WIRE -128 -440 -128 -456
WIRE 96 -440 -128 -440
WIRE 368 -440 368 -456
WIRE -240 -424 -576 -424
WIRE 144 -424 -240 -424
WIRE -352 -392 -352 -456
WIRE -240 -392 -240 -424
WIRE -128 -392 -128 -440
WIRE -576 -328 -576 -424
WIRE -464 -328 -576 -328
WIRE 16 -328 -16 -328
WIRE 48 -328 16 -328
WIRE 144 -328 144 -424
WIRE 144 -328 112 -328
WIRE 256 -312 256 -552
WIRE -576 -232 -576 -328
WIRE -560 -232 -576 -232
WIRE -464 -232 -480 -232
WIRE 208 -232 -16 -232
WIRE 16 -216 16 -328
WIRE -576 -136 -576 -232
WIRE -464 -136 -576 -136
WIRE 16 -136 16 -152
WIRE 16 -136 -16 -136
WIRE 256 -136 256 -216
WIRE 256 -136 16 -136
WIRE 304 -136 256 -136
WIRE 352 -136 304 -136
WIRE 464 -136 432 -136
WIRE 528 -136 464 -136
WIRE 672 -136 528 -136
WIRE 528 -120 528 -136
WIRE 672 -120 672 -136
WIRE 304 -104 304 -136
WIRE -464 -40 -480 -40
WIRE 16 -40 -16 -40
WIRE 144 -40 144 -328
WIRE 144 -40 16 -40
WIRE 144 -24 144 -40
WIRE 304 -24 304 -40
WIRE 528 -24 528 -56
WIRE 672 -24 672 -40
WIRE -576 56 -576 -136
WIRE -464 56 -576 56
WIRE 16 56 16 -40
WIRE 16 56 -16 56
WIRE 144 56 144 40
WIRE -592 152 -656 152
WIRE -464 152 -528 152
WIRE 464 152 464 -136
WIRE 464 152 -16 152
WIRE -640 248 -656 248
WIRE -544 248 -560 248
WIRE -464 248 -480 248
WIRE 256 248 256 -136
WIRE 256 248 -16 248
WIRE 256 264 256 248
WIRE 464 280 464 152
WIRE -544 344 -656 344
WIRE -464 344 -544 344
WIRE 208 344 -16 344
WIRE -656 360 -656 344
WIRE -544 360 -544 344
WIRE 464 392 464 360
WIRE 464 392 400 392
WIRE 464 408 464 392
WIRE -544 440 -544 424
WIRE -464 440 -544 440
WIRE 256 440 256 360
WIRE 256 440 -16 440
WIRE -656 456 -656 424
WIRE 256 456 256 440
WIRE 464 504 464 488
WIRE -352 520 -352 504
WIRE -128 520 -128 504
WIRE -656 552 -656 536
WIRE -544 552 -544 440
WIRE -544 552 -656 552
WIRE 400 552 400 392
WIRE 400 552 -544 552
FLAG 256 456 0
FLAG 144 56 0
FLAG 304 -24 0
FLAG -128 520 0
FLAG -352 520 0
FLAG 464 504 0
FLAG 528 -24 0
FLAG 672 -24 0
FLAG -656 152 0
FLAG 368 -440 0
FLAG 672 -136 OUT
FLAG 368 -552 IN
FLAG -480 -40 0
FLAG -656 248 0
SYMBOL res -368 -552 R0
SYMATTR InstName R1
SYMATTR Value 274K
SYMBOL nmos 96 -520 R0
SYMATTR InstName Q1
SYMATTR Value BSH114
SYMBOL res -144 -552 R0
SYMATTR InstName R2
SYMATTR Value 100K
SYMBOL diode 112 -344 R90
SYMATTR InstName D1
SYMATTR Value 1N4148
SYMBOL cap 0 -216 R0
SYMATTR InstName C1
SYMATTR Value .1
SYMBOL nmos 208 -312 R0
SYMATTR InstName Q2
SYMATTR Value Si7850DP
SYMBOL nmos 208 264 R0
SYMATTR InstName Q3
SYMATTR Value Si7850DP
SYMBOL cap 128 -24 R0
SYMATTR InstName C2
SYMATTR Value 1
SYMBOL ind 336 -120 R270
SYMATTR InstName L1
SYMATTR Value 7.7
SYMBOL schottky 288 -40 M180
SYMATTR InstName D2
SYMATTR Value MBRS1100
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 448 264 R0
SYMATTR InstName R3
SYMATTR Value 14K
SYMBOL res 448 392 R0
SYMATTR InstName R4
SYMATTR Value 1K
SYMBOL cap 512 -120 R0
SYMATTR SpiceLine Rser=10m
SYMATTR Value 270
SYMATTR InstName C3
SYMBOL cap -560 360 R0
SYMATTR InstName C4
SYMATTR Value 33p
SYMBOL cap -528 136 R90
SYMATTR InstName C5
SYMATTR Value 560p
SYMBOL res -464 -248 R90
SYMATTR InstName R5
SYMATTR Value 100K
SYMBOL cap -480 232 R90
SYMATTR InstName C6
SYMATTR Value .01
SYMBOL PowerProducts\\LTC3810 -240 56 R0
SYMATTR InstName U1
SYMBOL res -672 440 R0
SYMATTR InstName R6
SYMATTR Value 90.9K
SYMBOL cap -672 360 R0
SYMATTR InstName C7
SYMATTR Value 220p
SYMBOL res -544 232 R90
SYMATTR InstName R7
SYMATTR Value 10K
SYMBOL voltage 368 -552 R0
SYMATTR InstName V1
SYMATTR Value 24
SYMBOL res 656 -136 R0
SYMATTR InstName Rload
SYMATTR Value 3