1. Home
  2. Electronics Design
  3. Will this simple smps cct work.

Will this simple smps cct work.

Hi to all. Does anyone know if this simple cct will actually work. I have simulated it in LTSPICE and it seems to run ok , although the collector voltage is getting a bit high. I plan on winding the transformer on a small powdered iron toroid. I don't have the toroid yet , hence only the simulation to go on. As soon as I get what I need , I'll breadboard the cct. Just want to know if I'm wasting my time at this early stage :0)

Cheers Rob

Just save the following code as an .asc file and it should open fine.

Version 4 SHEET 1 1092 680 WIRE -368 208 -368 48 WIRE -368 448 -368 288 WIRE -144 48 -368 48 WIRE -144 96 -144 48 WIRE -144 288 -144 176 WIRE -16 48 -144 48 WIRE -16 112 -16 48 WIRE -16 224 -16 192 WIRE -16 288 -144 288 WIRE 112 48 -16 48 WIRE 112 144 112 112 WIRE 112 288 -16 288 WIRE 128 288 112 288 WIRE 176 48 112 48 WIRE 176 96 176 48 WIRE 176 224 112 224 WIRE 176 224 176 176 WIRE 176 240 176 224 WIRE 176 352 176 336 WIRE 176 448 -368 448 WIRE 176 448 176 432 WIRE 176 464 176 448 WIRE 272 96 272 16 WIRE 272 272 272 176 WIRE 416 272 272 272 WIRE 416 288 416 272 WIRE 432 16 336 16 WIRE 432 112 432 16 WIRE 432 272 416 272 WIRE 432 272 432 176 WIRE 528 16 432 16 WIRE 528 112 528 16 WIRE 528 272 432 272 WIRE 528 272 528 192 FLAG 176 464 0 FLAG 416 288 0 SYMBOL npn 112 240 R0 SYMATTR InstName Q1 SYMATTR Value 2N2219A SYMBOL ind2 160 80 R0 SYMATTR InstName L1 SYMATTR Value 100µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.5 SYMBOL res -160 80 R0 SYMATTR InstName R1 SYMATTR Value 4.7k SYMBOL voltage -368 192 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 12 SYMBOL ind2 0 208 R180 SYMATTR InstName L2 SYMATTR Value 2µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.2 SYMBOL cap -32 224 R0 SYMATTR InstName C2 SYMATTR Value 47n SYMBOL ind2 288 80 M0 WINDOW 0 -34 87 Left 0 WINDOW 3 -58 53 Left 0 SYMATTR InstName L3 SYMATTR Value 220µ SYMATTR Type ind SYMATTR SpiceLine Rser=0.8 SYMBOL cap 416 112 R0 SYMATTR InstName C3 SYMATTR Value 10µ SYMATTR SpiceLine V=25 Irms=0 Rser=0.001 MTBF=0 Lser=0 mfg="TDK" pn="C575OX7RIE106M" type="X7R" ppPkg=1 SYMBOL res 512 96 R0 SYMATTR InstName R3 SYMATTR Value 150 SYMBOL schottky 272 32 R270 WINDOW 0 32 32 VTop 0 WINDOW 3 0 32 VBottom 0 SYMATTR InstName D2 SYMATTR Value 1N5819 SYMATTR Description Diode SYMATTR Type diode SYMBOL res 160 336 R0 SYMATTR InstName R2 SYMATTR Value 4.7 SYMBOL cap 96 48 R0 SYMATTR InstName C1 SYMATTR Value 47n SYMBOL res 96 128 R0 SYMATTR InstName R4 SYMATTR Value 4.7 TEXT -72 416 Left 0 !.tran 60m startup TEXT 112 -16 Left 0 !k l1 l2 l3 1

Reply to
seegoon99
Loading thread data ...

The simulation shows that you're getting only 54% efficiency. That's sure to go down with real-world parts. I'd say you need to work to get the efficiency up before heating up your soldering iron.

Jim

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----

formatting link
The #1 Newsgroup Service in the World! >100,000 Newsgroups

---= 19 East/West-Coast Specialized Servers - Total Privacy via Encryption =---

Reply to
<rp0000003356

Try reversing the phase of L3. Then reduce C3 to 1N.

Re-couple L2 to ground, rather than 12V, to remove supply decoupling effects from the base drive. Suggest you re-check effects of supply voltage, C2 and load.

However: there's little reason to expect that a simulation, particularly of an oscillator, most particularly one using a simple magnetic component model, will accurately reflect reality.

RL

Reply to
legg

collector

a

breadboard

stage

Reply to
seegoon99

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.