Yes, that’s a good one. Look for low RDson and make sure it can handle the voltage of interest. 100v in this case.
I use 150v MOSFETs on mine so they can handle 300w amps - similar to Infineon BSC0402, for example.
I use 150v MOSFETs on mine so they can handle 300w amps - similar to Infineon BSC0402, for example.
The transistor must be capable to resist to a much higher voltage. The load is inductive and in case o a failure in the amplifier the current will refuse to stop when the SSR will open. The protection for transistors should be updated accordingly to the transistor voltage and amplifier power.
Thank you all.
Xrk,I see your options,hard to hand soldering, i see some other through hole high voltage and low RDon options in mouser too,0 stosk many of them.
I just look for available and not very expensive MOSFET.
I know...not an easy job.
Solder paste and hot plate is very easy and greatly opens up your options to low cost high performance parts.
https://www.sparkfun.com/tutorials/59
Here is a video of my hot plate:
https://www.sparkfun.com/tutorials/59
Here is a video of my hot plate:
I had tried this and works,i have tried using a high wattage car lamp too.
Maybe it's time for a diy reflow oven...
Maybe it's time for a diy reflow oven...
Going a little higher (like 150 or 200 volts) is of little help by itself. The voltage will try to spike many times the supply voltage when the relay “opens”. Adding a TVS, snubber, or another set of freewheeling diodes on the load side is what is required - and that will let you use the lower-Rds(on) 100 volt mosfets. If you used 600 volt mosfets it might still not be enough without other protection mechanisms - and will have much higher ON resistance to deal with.
Yes, a TVS across the back to back MOSFETs is key. Here is what I use for 150v MOSFET.
https://www.vishay.com/docs/88390/smaj50a.pdf
https://www.vishay.com/docs/88390/smaj50a.pdf
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Hi all,
I want to use the SSR3 with my Wolverine build. Would you recommend to use the secondary Zobel in this case?
Or in a more general way: When is it reasonable to use R100+C100?
@thimios I think you used the ssr protect with the Wolverine, too. May I ask which kind of supply you used, both, for the amp and for the protection?
Thank you!
I want to use the SSR3 with my Wolverine build. Would you recommend to use the secondary Zobel in this case?
Or in a more general way: When is it reasonable to use R100+C100?
@thimios I think you used the ssr protect with the Wolverine, too. May I ask which kind of supply you used, both, for the amp and for the protection?
Thank you!
Did you use a linear supply or an SMPS for the amp? I am asking because I will use an SMPS, and I think it's a bit more complicated to get the fast-off feature running with it.
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@LKA maybe you can give us a hint? I'm sure you've had your reasons to implement these two components. Thank you!
it is an optional part. some amplifiers don't have a zobel behind the output coil, this can help with better stability
@LKA if my understanding of the SSR3 circuit is correct, then the red LED will only light up in case of active overcurrent protection, while the green LED will turn off at any kind of active protection, e.g. DC. Is there a reason why you restricted the red LED to the overcurrent case?
The GREEN LED is in series with the optodriver's LED, so it indicates when SSR is engaged. The RED LED only signals overcurrent/overtemp/mute status. Why ? Due to the simplicity of the circuit.
You can skip RED and enjoy only GREEN 😀
You can skip RED and enjoy only GREEN 😀