Those are zener diodes. Regular rectifier diodes will not work.
The part numbers are shown; any equivalent zener should work.
edit: I Googled for the 1N41742A datasheet and it brought me right back here to diyAudio...
The part numbers are shown; any equivalent zener should work.
edit: I Googled for the 1N41742A datasheet and it brought me right back here to diyAudio...
Last edited:
1N4242 are listed as 3A rectifierdiods.
1N4142 NTE Equivalent NTE5804 400V 3A diode... - Wholesale Electronics
1N4142 NTE Equivalent NTE5804 400V 3A diode... - Wholesale Electronics
I'll take your word for it; I just don't see those in the schematic. 🙂
Have a look at the link I posted within the quote. There is a short FAQ and other build tips. There's also an explanation of the 1N383B. It's actually a 1N5383B.
Have a look at the link I posted within the quote. There is a short FAQ and other build tips. There's also an explanation of the 1N383B. It's actually a 1N5383B.
D5 and D6 and D7 and D8 protect the FETs from excessive gate to source voltage. If you look up the data sheet for the FETs you use it will give the Vgs maximum value. Take that figure and come down by around 20% for a good safety margin and select two zeners (low wattage) to suit (probably around 15 volt).
D1 protects against over voltage across the FET. Select a value lower than the maximum drain to source voltage for the FET used, again by perhaps 20 % as a safety margin.
D1 protects against over voltage across the FET. Select a value lower than the maximum drain to source voltage for the FET used, again by perhaps 20 % as a safety margin.
And just to add that D1 could have a tough life (and protest by failing short circuit) if you get it wrong. I would recommend looking for a FET for the series pass element that can withstand the unregulated full supply voltage across it rather than relying on a zener to protect an under rated FET.
Since D7 and D8 prevent the Vgs of Q3 from exceeding its Vgsmax specification, they need to be zener diodes whose Vz is less than 19 volts.
Since D5 and D6 prevent the Vgs of Q1 from exceeding its Vgsmax specification, they need to be zener diodes whose Vz is less than 19 volts.
D1 clamps the Vds of Q1 during turn-on and turn-off. I am not sure this is a good idea.
Since D5 and D6 prevent the Vgs of Q1 from exceeding its Vgsmax specification, they need to be zener diodes whose Vz is less than 19 volts.
D1 clamps the Vds of Q1 during turn-on and turn-off. I am not sure this is a good idea.
The Fairchild FQP3P50 is rated for 500 volts Vds and costs USD 1.17 in quantity=1 at DigiKey (page).
That right there is a Pchannel MOSFET that doesn't need a protection diode D1. No Sir. On the other hand, the wimpy IRF9610 certainly does need a protection diode D1.
I have soldered a irfbc40pbf to the pcb so I better use those 12v zeners (Vgs -+20v)
Ok,I´ll use a 1N5383 on IRF9610..
Ok,I´ll use a 1N5383 on IRF9610..
12V Zeners of 300mW, 400mW or 500mW will all work at protecting the gates.
D1 Zener may need to be very high power if it is asked to pass significant current at start up.
D1 Zener may need to be very high power if it is asked to pass significant current at start up.
One of my first jobs was selling electronic components and as far as I know there is no such thing as a "1N41742A".
I suspect what they meant was a 1N4742A which is a very standard 12 volt 1 watt zener diode. You will find the data on that series of zener diodes at http://www.rf-highvoltage.heliohost.org/spec-sheets/1N4728-49.pdf
As for D1 another zener diode "1N383B" which is the part number an ancient glass zener rated at 23.5 volts but only 200 mW and would be quickly fried if there was more than 200mW dissipated by it. I doubt you could ever find a 1N383 today.
With the typo's and the questionable D1 part number I would contact the author of the schematic.
I suspect what they meant was a 1N4742A which is a very standard 12 volt 1 watt zener diode. You will find the data on that series of zener diodes at http://www.rf-highvoltage.heliohost.org/spec-sheets/1N4728-49.pdf
As for D1 another zener diode "1N383B" which is the part number an ancient glass zener rated at 23.5 volts but only 200 mW and would be quickly fried if there was more than 200mW dissipated by it. I doubt you could ever find a 1N383 today.
With the typo's and the questionable D1 part number I would contact the author of the schematic.
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