New Improved +/-45V PSU

[Harry Dellamano]

After seeing the group's 45V power supply kludge, I would like to enter
mine into the competition.

Version 4
SHEET 1 1108 900
WIRE -816 -256 -1200 -256
WIRE -576 -256 -816 -256
WIRE -80 -256 -576 -256
WIRE -1632 -240 -1680 -240
WIRE -1504 -240 -1552 -240
WIRE -1488 -240 -1504 -240
WIRE -576 -192 -576 -256
WIRE -816 -176 -816 -256
WIRE -864 -160 -944 -160
WIRE -1856 -128 -1952 -128
WIRE -1680 -128 -1680 -240
WIRE -1456 -128 -1680 -128
WIRE -80 -128 -80 -256
WIRE -944 -112 -944 -160
WIRE -256 -112 -288 -112
WIRE -128 -112 -176 -112
WIRE -1200 -80 -1200 -256
WIRE -1952 -64 -1952 -128
WIRE -576 -48 -576 -112
WIRE -1456 -16 -1456 -128
WIRE -1360 -16 -1456 -16
WIRE -992 16 -1040 16
WIRE -864 16 -864 -112
WIRE -864 16 -992 16
WIRE -816 16 -816 -96
WIRE -688 16 -816 16
WIRE -288 16 -288 -112
WIRE -288 16 -688 16
WIRE -1680 48 -1680 -128
WIRE -1632 48 -1680 48
WIRE -1520 48 -1568 48
WIRE -1408 48 -1440 48
WIRE -1360 48 -1408 48
WIRE -1680 80 -1680 48
WIRE -768 96 -816 96
WIRE -752 96 -768 96
WIRE -432 96 -464 96
WIRE -320 96 -368 96
WIRE -192 96 -240 96
WIRE -1440 112 -1472 112
WIRE -1376 112 -1440 112
WIRE -1360 112 -1376 112
WIRE -80 112 -80 -32
WIRE -1472 128 -1472 112
WIRE -816 128 -816 96
WIRE -1024 144 -1040 144
WIRE -976 144 -1024 144
WIRE -912 144 -976 144
WIRE -864 144 -864 16
WIRE -1360 176 -1392 176
WIRE -464 208 -464 96
WIRE -464 208 -576 208
WIRE -352 208 -464 208
WIRE -192 208 -192 96
WIRE -192 208 -288 208
WIRE -80 208 -80 112
WIRE 32 208 -80 208
WIRE 192 208 96 208
WIRE 288 208 192 208
WIRE -1472 224 -1472 208
WIRE -1392 224 -1392 176
WIRE -1392 224 -1472 224
WIRE -1472 240 -1472 224
WIRE -576 240 -576 208
WIRE -192 240 -192 208
WIRE -80 240 -80 208
WIRE 288 240 288 208
WIRE -464 256 -464 208
WIRE 192 256 192 208
WIRE -912 272 -912 144
WIRE -1200 288 -1200 240
WIRE -816 288 -816 224
WIRE -736 288 -816 288
WIRE -816 352 -816 288
WIRE -816 352 -864 352
WIRE -576 368 -576 320
WIRE -464 368 -464 320
WIRE -192 368 -192 320
WIRE -80 368 -80 320
WIRE 192 368 192 320
WIRE 288 368 288 320
WIRE -1376 384 -1376 112
WIRE -1312 384 -1376 384
WIRE -1024 384 -1024 144
WIRE -1024 384 -1232 384
WIRE -1024 400 -1024 384
FLAG -576 -48 0
FLAG -80 368 0
FLAG 192 368 0
FLAG -192 368 0
FLAG -464 368 0
FLAG -576 368 0
FLAG 288 368 0
FLAG -80 112 VS
FLAG 288 208 NO
FLAG -576 208 PO
FLAG -1200 288 0
FLAG -992 16 DV
FLAG -688 16 DN
FLAG -1472 304 0
FLAG -1472 224 FR
FLAG -736 368 0
FLAG -1024 464 0
FLAG -912 368 0
FLAG -1440 112 VR
FLAG -768 96 VR
FLAG -976 144 IS
FLAG -944 -112 0
FLAG -1680 160 0
FLAG -1504 -240 PO
FLAG -1408 48 CP
FLAG -1952 16 0
FLAG -1792 -128 CP
SYMBOL ind2 -96 224 R0
WINDOW 0 50 51 Left 2
WINDOW 3 60 86 Left 2
SYMATTR InstName L1
SYMATTR Value 220µ
SYMATTR Type ind
SYMATTR SpiceLine Rser=1.72
SYMBOL cap -480 256 R0
SYMATTR InstName C1
SYMATTR Value 1µ
SYMBOL schottky 96 224 M270
WINDOW 0 32 32 VTop 2
WINDOW 3 -3 -7 VBottom 2
SYMATTR InstName D1
SYMATTR Value MBRS1100
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL voltage -576 -208 R0
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR InstName V1
SYMATTR Value 16
SYMBOL schottky -288 224 M270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D3
SYMATTR Value MBRS1100
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL cap 208 320 R180
WINDOW 0 24 56 Left 2
WINDOW 3 24 8 Left 2
SYMATTR InstName C6
SYMATTR Value 1µ
SYMBOL res -592 224 R0
WINDOW 3 25 4 Left 2
SYMATTR Value 2.2k
SYMATTR InstName R2
SYMBOL res 272 224 R0
SYMATTR InstName R4
SYMATTR Value 2.2k
SYMBOL res -160 -128 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R1
SYMATTR Value 20
SYMBOL ind2 -208 336 M180
WINDOW 0 36 80 Left 2
WINDOW 3 36 40 Left 2
SYMATTR InstName L2
SYMATTR Value 220µ
SYMATTR Type ind
SYMATTR SpiceLine Rser=1.72
SYMBOL pmos -128 -32 M180
SYMATTR InstName M2
SYMATTR Value IRF9640
SYMBOL e -816 -192 R0
SYMATTR InstName E1
SYMATTR Value -1
SYMBOL res -1488 112 R0
SYMATTR InstName R3
SYMATTR Value 30K
SYMBOL cap -1488 240 R0
SYMATTR InstName C2
SYMATTR Value 470p
SYMBOL res -1216 368 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R6
SYMATTR Value 30K
SYMBOL cap -1040 400 R0
SYMATTR InstName C3
SYMATTR Value 1n
SYMBOL pmos -864 224 M180
SYMATTR InstName M1
SYMATTR Value BSS84
SYMBOL nmos -864 272 M0
SYMATTR InstName M3
SYMATTR Value 2N7002
SYMBOL res -752 272 R0
SYMATTR InstName R5
SYMATTR Value 2K
SYMBOL res -1696 64 R0
SYMATTR InstName R7
SYMATTR Value 10K
SYMBOL res -1536 -256 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R8
SYMATTR Value 170K
SYMBOL cap -1568 32 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C4
SYMATTR Value 100n
SYMBOL res -1424 32 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R9
SYMATTR Value 68K
SYMBOL PowerProducts\\LT1242 -1200 80 R0
SYMATTR InstName U1
SYMBOL voltage -1952 -80 R0
WINDOW 3 -49 325 Left 2
WINDOW 123 0 0 Left 2
WINDOW 39 0 0 Left 2
SYMATTR Value PULSE(0 4 5n 2m 10n 10M 30m)
SYMATTR InstName V2
SYMBOL diode -1792 -144 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName D2
SYMBOL res -224 80 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 37 48 VTop 2
SYMATTR InstName R11
SYMATTR Value 220
SYMBOL cap -368 80 R90
WINDOW 0 0 32 VBottom 2
WINDOW 3 32 32 VTop 2
SYMATTR InstName C5
SYMATTR Value 120p
TEXT -912 -352 Left 2 !.tran 0 4MU 0 100N
TEXT -216 424 Left 2 !K L1 L2 0.9965
TEXT -216 472 Left 2 ;MSD7342-224

The design still needs a soft start, high side driver and stability
analysis. Once the input voltage range is known the design can be completed.
The magnetics is an OTS coupled choke from Coilcraft. The MOSFET needs
replacement by a <1.0R 80V device, it was the only model in LTSpice.

Cheers,
Harry