Yes, easy. Just look for 600v capable N Chan MOSFETs with RDson relatively low (I am using 190mOhm but ideally less is better) and capable of 30A or so in TO-220.
This will work.
https://www.mouser.com/ProductDetail/STMicroelectronics/STP36N60M6?qs=5aG0NVq1C4woHzCBhnZUwA==
This will work.
https://www.mouser.com/ProductDetail/STMicroelectronics/STP36N60M6?qs=5aG0NVq1C4woHzCBhnZUwA==
Both, my preamplifier puts out 12V 20 ma for remote turn on. I was going to put it on the outlets from my line filter I am building but my SWPS amps all have a standby mode with 12v trigger.Truth be known I would prefer them to remain on than slamming power on and off. This is one application a relay may be ok if the contacts froze it would just leave the power on.
PS the 12v comes on after delay and remains in until power off of the preamp.
Bill
PS the 12v comes on after delay and remains in until power off of the preamp.
Bill
Trigger toggle would be neat, more ideal would be some sort of trigger detection circuit, but I imagine that would be fairly component heavy compared to a toggle?
Simplest would be a small 12v momentary relay. Use that to drive the SFPP. However, it toggles so a click turns on and next click turns off.
If you have 12v 10mA as always on or off depending on state, that’s a bit more complicated. Or drive the opto isolator directly with that 10mA current.
If you have 12v 10mA as always on or off depending on state, that’s a bit more complicated. Or drive the opto isolator directly with that 10mA current.
You mean DPDT momentary? It retracts to center position and only momentarily contacts on or off.
https://a.co/d/iL2e7Zg
https://a.co/d/iL2e7Zg
Hi folks, I've assembled the SFPP board over the last couple days and having an issue. The standby and on LED's are cycling as intended with the momentary switch, but I am not getting any AC voltage to the outputs and the SMD LED is not lighting. I did a little bit of diagnosis and I think the issue might lie with the comparator at U4. On standby the voltage to pin 3 referenced to ground is 0v, in the on position it's 4.7v. For pin 4 the voltage is 5v on standby and 3.9v in the on position. I'm getting just under 1 volt across D4 in the on position (and 0V in standby). Hardly sufficient. Is there an issue with U4 or is the problem somewhere else?
Hi JWCoffman,
Sorry I didn’t see this earlier. Please check U3 (flip flop) for solder bridges. It’s a tiny finicky chip and I had to use copper braid and liquid flux to clean up the pins post hot plate soldering.
Make sure pin 6 is not shorted to GND. Also, if you say that the pushbutton toggles the LEDs that means the dual NAND switch debounce is working correctly and the U3 is working.
Check the orientation of D4, if that’s backwards, you won’t turn on the opto and the MOSFETs won’t turn on. But they are for bypassing the NTCs.
Check orientation of U6.
You should have AC coming through the triac. If no AC at all, check orientation of the opto U5. If flipped, it wont drive the opto.
Be careful not to connect a large high current load until you verify it works well with a small higher impedance load (5W 1k resistor etc). A large trafo and logic glitching can fry the triac or MOSFETs or NTCs.
A high res closeup photo of your assembled PCB would be helpful.
Sorry I didn’t see this earlier. Please check U3 (flip flop) for solder bridges. It’s a tiny finicky chip and I had to use copper braid and liquid flux to clean up the pins post hot plate soldering.
Make sure pin 6 is not shorted to GND. Also, if you say that the pushbutton toggles the LEDs that means the dual NAND switch debounce is working correctly and the U3 is working.
Check the orientation of D4, if that’s backwards, you won’t turn on the opto and the MOSFETs won’t turn on. But they are for bypassing the NTCs.
Check orientation of U6.
You should have AC coming through the triac. If no AC at all, check orientation of the opto U5. If flipped, it wont drive the opto.
Be careful not to connect a large high current load until you verify it works well with a small higher impedance load (5W 1k resistor etc). A large trafo and logic glitching can fry the triac or MOSFETs or NTCs.
A high res closeup photo of your assembled PCB would be helpful.
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Thanks for the response. I did check for bridges when I first soldered them on and had to clean up one spot. I just double checked again and there don't seem to be any bridges except on U3 where pins 2 and 3 and pins 7 and 8 are bridged on the PCB itself. Pin 6 of U3 is not shorted to ground, and U6 seems to be oriented correctly. I also double-checked the orientation of D6, and it seems to be correct.
My PCB is below with the caveat that I'm still new to SMD soldering. My joints are ugly and my devices are askew, but I'm fairly certain they are functional.
My PCB is below with the caveat that I'm still new to SMD soldering. My joints are ugly and my devices are askew, but I'm fairly certain they are functional.
Thanks for the photo. It looks like you did this with a soldering iron and not paste and hot air/hot plate? It’s very difficult to do 0603 and those tiny 0.5mm pitch ICs with a soldering iron.
Please reflow the resistor on the opto for the triac. Looks like a cold solder joint.
Swap out the misplaced resistor on the NAND gate with correct 0.1uF bypass cap.
Use copper braid solder wick and liquid flux and chisel to clean up little balls on the pins at U3 and U4. They may cause intermittent shorts.
Please reflow the resistor on the opto for the triac. Looks like a cold solder joint.
Swap out the misplaced resistor on the NAND gate with correct 0.1uF bypass cap.
Use copper braid solder wick and liquid flux and chisel to clean up little balls on the pins at U3 and U4. They may cause intermittent shorts.