Re: P-channel MOSFET model

On 06/05/2024 06:58, Edward Rawde wrote:

"John Larkin" <jjSNIPlarkin@highNONOlandtechnology.com> wrote in message
news:aesf3j1po3glh1c23se3lofoni6j7ol75m@4ax.com...

On Sun, 5 May 2024 14:42:30 -0400, "Edward Rawde"
<invalid@invalid.invalid> wrote:
>

"Edward Rawde" <invalid@invalid.invalid> wrote in message
news:v16s2i$2uv4$1@nnrp.usenet.blueworldhosting.com...

Does anyone know of a P-channel MOSFET, roughly equivalent to
XP233P1501TR-G which has a model I can use in LTSpice?
XP202A0003PR-G would be useful too.

>
Infineon BSS215P  might be more suitable for the FET.
That does have a simulation model.
http://www.infineon.com/dgdl/Infineon-SimulationModel_OptiMOS_PowerMOSFET_PSpice_20V_P-Channel-SM-v01_00-EN.zip?fileId=db3a30433d346a2d013d493ff9d160ab
I'll have to look into how compatible the model is with LTspice.
>
Microchip TC105 is also interesting but a bit pricey.
However it does lead to CD54NP as a possible choice for the inductor.
MA737 doesn't seem to be easily available but a suitable shottky diode
shouldn't be hard to find.
>
Vishay SI2371EDS-T1-GE3 looks interesting too.
Not too pricey for lower on resistance.
>

>
>

>

>
Some of the TI TPS5- series buck switchers are 19 cents.
>
Your circuit looks like a good way to blow up transistors.
>

 Here's 12V to 5V 1A using the concept I had in mind of using a comparator
capacitively coupled to a FET.
Also using only components I could find in a fresh install of LTSpice.
If it doesn't work, fix the character encoding issue in the value of some
components.
 Don't worry it won't be going into production any time soon.
 Comments/laugter is welcome.
 Version 4
SHEET 1 1956 680
WIRE 1104 -80 368 -80
WIRE 368 -16 368 -80
WIRE 368 -16 304 -16
WIRE 432 -16 368 -16
WIRE 544 -16 432 -16
WIRE 672 -16 544 -16
WIRE 848 -16 768 -16
WIRE 928 -16 848 -16
WIRE 1232 -16 1008 -16
WIRE 1376 -16 1232 -16
WIRE 1520 -16 1376 -16
WIRE 1632 -16 1520 -16
WIRE 304 32 304 -16
WIRE 1104 32 1104 -80
WIRE 1232 32 1232 -16
WIRE 544 64 544 -16
WIRE 432 80 432 -16
WIRE 1376 96 1376 -16
WIRE 1376 96 1360 96
WIRE 848 112 848 -16
WIRE 1632 112 1632 -16
WIRE 1360 128 1360 96
WIRE 1376 128 1376 96
WIRE 1520 128 1520 -16
WIRE 1104 144 1104 112
WIRE 1328 144 1104 144
WIRE 1456 160 1392 160
WIRE 304 176 304 112
WIRE 544 176 544 144
WIRE 592 176 544 176
WIRE 688 176 688 32
WIRE 688 176 656 176
WIRE 1232 176 1232 112
WIRE 1328 176 1232 176
WIRE 1104 192 1104 144
WIRE 1232 192 1232 176
WIRE 544 208 544 176
WIRE 688 224 688 176
WIRE 304 336 304 256
WIRE 432 336 432 144
WIRE 432 336 304 336
WIRE 544 336 544 288
WIRE 544 336 432 336
WIRE 848 336 848 176
WIRE 848 336 544 336
WIRE 1104 336 1104 272
WIRE 1104 336 848 336
WIRE 1232 336 1232 272
WIRE 1232 336 1104 336
WIRE 1344 336 1344 192
WIRE 1344 336 1232 336
WIRE 1360 336 1360 192
WIRE 1360 336 1344 336
WIRE 1376 336 1376 192
WIRE 1376 336 1360 336
WIRE 1520 336 1520 192
WIRE 1520 336 1376 336
WIRE 1632 336 1632 192
WIRE 1632 336 1520 336
WIRE 304 352 304 336
WIRE 688 400 688 288
WIRE 1456 400 1456 160
WIRE 1456 400 688 400
FLAG 304 352 0
SYMBOL Comparators\LT1719 1360 96 R0
WINDOW 0 37 82 Left 2
WINDOW 3 26 27 Left 2
SYMATTR InstName U1
SYMBOL res 1088 16 R0
WINDOW 0 -36 27 Left 2
WINDOW 3 -71 76 Left 2
SYMATTR InstName R1
SYMATTR Value 47.5K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL res 1088 176 R0
WINDOW 0 -43 30 Left 2
WINDOW 3 -59 64 Left 2
SYMATTR InstName R2
SYMATTR Value 10K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL ind 1024 -32 R90
WINDOW 0 66 46 VBottom 2
WINDOW 3 -27 53 VTop 2
SYMATTR InstName L1
SYMATTR Value 47µ
SYMATTR SpiceLine Ipk=1.1 Rser=0.17 Rpar=0 Cpar=0 mfg="Sumida"
pn="CD104-470"
SYMBOL res 1616 96 R0
SYMATTR InstName R4
SYMATTR Value 5.1
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL res 1216 16 R0
WINDOW 0 -40 27 Left 2
WINDOW 3 -50 74 Left 2
SYMATTR InstName R3
SYMATTR Value 14K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL res 1216 176 R0
WINDOW 0 -42 26 Left 2
WINDOW 3 -51 67 Left 2
SYMATTR InstName R5
SYMATTR Value 10K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL polcap 1504 128 R0
WINDOW 3 24 56 Left 2
SYMATTR Value 100µ
SYMATTR InstName C1
SYMATTR Description Capacitor
SYMATTR Type cap
SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.9 Lser=0 mfg="AVX" pn="TAJD107M006"
type="Tantalum"
SYMBOL schottky 864 176 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D2
SYMATTR Value DFLS220L
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL pmos 768 32 M270
WINDOW 0 -18 59 VLeft 2
WINDOW 3 78 89 VLeft 2
SYMATTR InstName M1
SYMATTR Value AO6407
SYMBOL voltage 304 160 R0
WINDOW 0 11 100 Left 2
WINDOW 3 38 54 Left 2
WINDOW 123 0 0 Left 0
WINDOW 39 -185 81 Left 2
SYMATTR InstName V3
SYMATTR Value 12
SYMBOL res 528 48 R0
SYMATTR InstName R6
SYMATTR Value 1K
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL res 528 192 R0
WINDOW 3 -71 61 Left 2
SYMATTR Value 2.32K
SYMATTR InstName R7
SYMATTR SpiceLine tol=1 pwr=0.1
SYMBOL cap 672 224 R0
SYMATTR InstName C4
SYMATTR Value 0.01µ
SYMATTR SpiceLine V=16 Irms=0 Rser=0.0158 Lser=350p mfg="Würth Elektronik"
pn="885012008017 WCAP-CSGP 1206" type="NP0"
SYMBOL polcap 416 80 R0
WINDOW 3 24 56 Left 2
SYMATTR Value 100µ
SYMATTR InstName C2
SYMATTR Description Capacitor
SYMATTR Type cap
SYMATTR SpiceLine V=6.3 Irms=0 Rser=0.9 Lser=0 mfg="AVX" pn="TAJD107M006"
type="Tantalum"
SYMBOL diode 592 192 R270
WINDOW 0 32 32 VTop 2
WINDOW 3 0 32 VBottom 2
SYMATTR InstName D3
SYMATTR Value 1N4148
SYMBOL res 288 16 R0
SYMATTR InstName R8
SYMATTR Value 0.001
TEXT 288 392 Left 2 !.tran 0.001 startup
   

LED loads shouldn't care if ground referenced or not so you could use a N-channel MOSFET instead - saves a cent and gives more choice of device.
LEDs shouldn't mind if the current is not smooth. If the inductor is big enough the current can be kept approximately continuous and you can save the output capacitor - perhaps the least long lived part in real life.
Here is my idea of a simple converter, biggest efficiency hit is probably the sense resistor R5. I think the hysteresis determined by R3 may need fine tuning. This circuit has no capacitors, timing is dictated by the inductor solely. I think adding a small capacitor from M1 drain to Q1 collector could extend on-time and improve gate drive? Lots of scope for fiddling.
Version 4
SHEET 1 1256 680
WIRE 64 -112 -144 -112
WIRE 256 -112 64 -112
WIRE 496 -112 256 -112
WIRE 752 -112 496 -112
WIRE 752 -96 752 -112
WIRE 64 -32 64 -112
WIRE 752 16 752 -16
WIRE 752 16 128 16
WIRE 256 64 256 -112
WIRE 64 96 64 64
WIRE 496 96 496 -112
WIRE 752 96 752 16
WIRE -144 144 -144 -112
WIRE 64 192 64 176
WIRE 128 192 64 192
WIRE 496 192 496 160
WIRE 496 192 208 192
WIRE 496 224 496 192
WIRE 544 224 496 224
WIRE 752 224 752 160
WIRE 752 224 624 224
WIRE 496 240 496 224
WIRE 256 320 256 144
WIRE 448 320 256 320
WIRE 256 336 256 320
WIRE 64 384 64 192
WIRE 192 384 64 384
WIRE 64 400 64 384
WIRE -144 496 -144 224
WIRE 64 496 64 480
WIRE 64 496 -144 496
WIRE 256 496 256 432
WIRE 256 496 64 496
WIRE 496 496 496 336
WIRE 496 496 256 496
WIRE -144 560 -144 496
FLAG -144 560 0
SYMBOL voltage -144 128 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 12
SYMBOL nmos 448 240 R0
SYMATTR InstName M1
SYMATTR Value FDS6612A
SYMBOL schottky 512 160 R180
WINDOW 0 24 64 Left 2
WINDOW 3 24 0 Left 2
SYMATTR InstName D1
SYMATTR Value 1N5817
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL ind 640 208 R90
WINDOW 0 5 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName L1
SYMATTR Value 220µ
SYMBOL LED 736 96 R0
SYMATTR InstName D2
SYMATTR Value LXK2-PW14
SYMATTR Description Diode
SYMATTR Type diode
SYMBOL res 736 -112 R0
SYMATTR InstName R5
SYMATTR Value 1.2
SYMBOL res 240 48 R0
SYMATTR InstName R4
SYMATTR Value 3k
SYMBOL pnp 128 64 R180
SYMATTR InstName Q1
SYMATTR Value 2N3906
SYMBOL res 48 384 R0
SYMATTR InstName R2
SYMATTR Value 3k
SYMBOL res 224 176 R90
WINDOW 0 0 56 VBottom 2
WINDOW 3 32 56 VTop 2
SYMATTR InstName R3
SYMATTR Value 62k
SYMBOL npn 192 336 R0
SYMATTR InstName Q2
SYMATTR Value 2N3904
SYMBOL res 48 80 R0
SYMATTR InstName R1
SYMATTR Value 3k
TEXT 736 560 Left 2 !.tran 10m
TEXT 664 400 Left 2 ;EPW SED May 2024
TEXT 624 448 Left 2 ;Simple LED buck smps
piglet