I'm updating some game board designs and was curious if there is any
sort of printed guideline for replacing silicon driver transistors with
MOS? Both NPN and PNP.
For example TIP122 Darlington transistors driven by another pre-driver,
that is the TTL interface. I've seen many a substitute, but would like
to have the theory explained so I can make better use of it and
understand exactly what I am doing.
A good reference book you can recommend perhaps? Books and I usually get
along very well.
Too many projects and not enough to hunt down all the solutions!
Thanks, and sorry for the on-topic post...
John :-#)#
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
#7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
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"Old pinballers never die, they just flip out."
Rule of thumb for replacing power transistors with MOSFets?
Started by ●March 15, 2023
Reply by ●March 15, 20232023-03-15
On Wed, 15 Mar 2023 12:00:02 -0700, John Robertson <jrr@flippers.com> wrote:>I'm updating some game board designs and was curious if there is any >sort of printed guideline for replacing silicon driver transistors with >MOS? Both NPN and PNP. > >For example TIP122 Darlington transistors driven by another pre-driver, >that is the TTL interface. I've seen many a substitute, but would like >to have the theory explained so I can make better use of it and >understand exactly what I am doing.TTL can drive low-threshold, aka logic level, fets. There might be a base voltage divider that you can booger to get maximum voltage swing. I like FDV301 for low current, 0.2 amp loads. STD16NF06 for heftier stuff; it will easily sink 15 amps with +5 on the gate.> >A good reference book you can recommend perhaps? Books and I usually get >along very well. > >Too many projects and not enough to hunt down all the solutions! > >Thanks, and sorry for the on-topic post...Just don't let that happen again.> >John :-#)#
Reply by ●March 15, 20232023-03-15
On 2023/03/15 2:05 p.m., John Larkin wrote:> On Wed, 15 Mar 2023 12:00:02 -0700, John Robertson <jrr@flippers.com> > wrote: > >> I'm updating some game board designs and was curious if there is any >> sort of printed guideline for replacing silicon driver transistors with >> MOS? Both NPN and PNP. >> >> For example TIP122 Darlington transistors driven by another pre-driver, >> that is the TTL interface. I've seen many a substitute, but would like >> to have the theory explained so I can make better use of it and >> understand exactly what I am doing. > > TTL can drive low-threshold, aka logic level, fets. There might be a > base voltage divider that you can booger to get maximum voltage swing. > > I like FDV301 for low current, 0.2 amp loads. STD16NF06 for heftier > stuff; it will easily sink 15 amps with +5 on the gate.Digikey, Mouser, and Newark are all months away from having stock on the STD16NF06...could use the STD25N10F7 I suppose - a bit of overkill. Oh, well, I'll just look for TTL compatible I guess - I just thought there might be some theory behind it that I could brush up on. Not that I ever really understood transistors, too much magic in those parameters! John :-#(#> >> >> A good reference book you can recommend perhaps? Books and I usually get >> along very well. >> >> Too many projects and not enough to hunt down all the solutions! >> >> Thanks, and sorry for the on-topic post... > > Just don't let that happen again. > > >> >> John :-#)#-- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."
Reply by ●March 15, 20232023-03-15
On Wed, 15 Mar 2023 16:51:32 -0700, John Robertson <jrr@flippers.com> wrote:>On 2023/03/15 2:05 p.m., John Larkin wrote: >> On Wed, 15 Mar 2023 12:00:02 -0700, John Robertson <jrr@flippers.com> >> wrote: >> >>> I'm updating some game board designs and was curious if there is any >>> sort of printed guideline for replacing silicon driver transistors with >>> MOS? Both NPN and PNP. >>> >>> For example TIP122 Darlington transistors driven by another pre-driver, >>> that is the TTL interface. I've seen many a substitute, but would like >>> to have the theory explained so I can make better use of it and >>> understand exactly what I am doing. >> >> TTL can drive low-threshold, aka logic level, fets. There might be a >> base voltage divider that you can booger to get maximum voltage swing. >> >> I like FDV301 for low current, 0.2 amp loads. STD16NF06 for heftier >> stuff; it will easily sink 15 amps with +5 on the gate. > >Digikey, Mouser, and Newark are all months away from having stock on the >STD16NF06...could use the STD25N10F7 I suppose - a bit of overkill. > >Oh, well, I'll just look for TTL compatible I guess - I just thought >there might be some theory behind it that I could brush up on. Not that >I ever really understood transistors, too much magic in those parameters! > >John :-#(# > >>There are lots of "logic level" low-thresold p and n channel fets around. I just named a couple that we use. If you post a link to your schematic(s) we could check the circuits for drive compatibility.>>> >>> A good reference book you can recommend perhaps? Books and I usually get >>> along very well. >>> >>> Too many projects and not enough to hunt down all the solutions! >>> >>> Thanks, and sorry for the on-topic post... >> >> Just don't let that happen again. >> >> >>> >>> John :-#)#
Reply by ●March 16, 20232023-03-16
On a sunny day (Wed, 15 Mar 2023 12:00:02 -0700) it happened John Robertson <jrr@flippers.com> wrote in <tut4jn$10ok6$1@dont-email.me>:>I'm updating some game board designs and was curious if there is any >sort of printed guideline for replacing silicon driver transistors with >MOS? Both NPN and PNP. > >For example TIP122 Darlington transistors driven by another pre-driver, >that is the TTL interface. I've seen many a substitute, but would like >to have the theory explained so I can make better use of it and >understand exactly what I am doing. > >A good reference book you can recommend perhaps? Books and I usually get >along very well. > >Too many projects and not enough to hunt down all the solutions! > >Thanks, and sorry for the on-topic post... > >John :-#)#This is how MOSFETs work: https://en.wikipedia.org/wiki/MOSFET If you want to use one: there are basically 2 types: some conduct with zero volts at the gate and some do not conduct with zero volts at the gate. To interface with 5V logic I usually use an IRFZ44A MOSFET (off when 0V at the gate). 10 for $8.63 on ebay.. https://www.ebay.com/itm/324380901727 even cheaper at other places datasheet: https://datasheetspdf.com/pdf-file/799031/Samsung/IRFZ44A/1 look at page 3 figure 2 for at what voltage the thing starts conducting. At 5 V from TTL logic it can do several amps. MOSFETS do not pose a current drain on the driver (very high impedance, these should work for a pinball machine I'd think). Also these MOSFETS have a reverse diode that limits the peak voltages when switching an inductive load, see figure 13 in that datasheet (may save you a protection diode, but of course you can leave it in too). So this is a "simple practicle man's few lines book" but you gotta start somewhere... More in my book 'The Fart Of Electronics' provided I ever can find a decent pen to write it. There also exists a book 'The art of electronics' I'v never read it but people get all exited about it it seems. The author used to post here...
Reply by ●March 16, 20232023-03-16
On Wednesday, March 15, 2023 at 3:00:19 PM UTC-4, John Robertson wrote:> I'm updating some game board designs and was curious if there is any > sort of printed guideline for replacing silicon driver transistors with > MOS? Both NPN and PNP. > > For example TIP122 Darlington transistors driven by another pre-driver, > that is the TTL interface. I've seen many a substitute, but would like > to have the theory explained so I can make better use of it and > understand exactly what I am doing. > > A good reference book you can recommend perhaps? Books and I usually get > along very well. > > Too many projects and not enough to hunt down all the solutions!Unless there's an availability problem with the bipolar, leave it. As far as any rules of thumb: don't touch a hot case with your bare thumb.> > Thanks, and sorry for the on-topic post...You're one of these whiners always complaining about the group content, while contributing little to nothing yourself.> > John :-#)# > > -- > (Please post followups or tech inquiries to the USENET newsgroup) > John's Jukes Ltd. > #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 > (604)872-5757 (Pinballs, Jukes, Video Games) > www.flippers.com > "Old pinballers never die, they just flip out."
Reply by ●March 16, 20232023-03-16
On Thu, 16 Mar 2023 05:06:35 -0700 (PDT), Fred Bloggs <bloggs.fredbloggs.fred@gmail.com> wrote:>On Wednesday, March 15, 2023 at 3:00:19?PM UTC-4, John Robertson wrote: >> I'm updating some game board designs and was curious if there is any >> sort of printed guideline for replacing silicon driver transistors with >> MOS? Both NPN and PNP. >> >> For example TIP122 Darlington transistors driven by another pre-driver, >> that is the TTL interface. I've seen many a substitute, but would like >> to have the theory explained so I can make better use of it and >> understand exactly what I am doing. >> >> A good reference book you can recommend perhaps? Books and I usually get >> along very well. >> >> Too many projects and not enough to hunt down all the solutions! > >Unless there's an availability problem with the bipolar, leave it. As far as any rules of thumb: don't touch a hot case with your bare thumb. > >> >> Thanks, and sorry for the on-topic post... > >You're one of these whiners always complaining about the group content, while contributing little to nothing yourself. > >> >> John :-#)#Hey, your kettle's black. Just deleted at least ten of your most recent posts as being OT. RL
Reply by ●March 16, 20232023-03-16
On 3/16/2023 8:06 AM, Fred Bloggs wrote:> You're one of these whiners always complaining about the group content, while contributing little to nothing yourself.You have something personal against John?
Reply by ●March 16, 20232023-03-16
On Thu, 16 Mar 2023 07:15:30 GMT, Jan Panteltje <alien@comet.invalid> wrote:>On a sunny day (Wed, 15 Mar 2023 12:00:02 -0700) it happened John Robertson ><jrr@flippers.com> wrote in <tut4jn$10ok6$1@dont-email.me>: > >>I'm updating some game board designs and was curious if there is any >>sort of printed guideline for replacing silicon driver transistors with >>MOS? Both NPN and PNP. >> >>For example TIP122 Darlington transistors driven by another pre-driver, >>that is the TTL interface. I've seen many a substitute, but would like >>to have the theory explained so I can make better use of it and >>understand exactly what I am doing. >> >>A good reference book you can recommend perhaps? Books and I usually get >>along very well. >> >>Too many projects and not enough to hunt down all the solutions! >> >>Thanks, and sorry for the on-topic post... >> >>John :-#)# > >This is how MOSFETs work: >https://en.wikipedia.org/wiki/MOSFET > > >If you want to use one: there are basically 2 types: some conduct with zero volts at the gate >and some do not conduct with zero volts at the gate. > >To interface with 5V logic I usually use an IRFZ44A MOSFET (off when 0V at the gate). >10 for $8.63 on ebay.. > https://www.ebay.com/itm/324380901727 >even cheaper at other places >datasheet: > https://datasheetspdf.com/pdf-file/799031/Samsung/IRFZ44A/1 > >look at page 3 figure 2 for at what voltage the thing starts conducting. > >At 5 V from TTL logic it can do several amps.Note that 74-series TTL does not pull up to 5 volts.>MOSFETS do not pose a current drain on the driver (very high impedance, these should work for a pinball machine I'd think). >Also these MOSFETS have a reverse diode that limits the peak voltages when switching an inductive load, >see figure 13 in that datasheet (may save you a protection diode, but of course you can leave it in too). > >So this is a "simple practicle man's few lines book" but you gotta start somewhere... > >More in my book 'The Fart Of Electronics' provided I ever can find a decent pen to write it. > >There also exists a book 'The art of electronics' I'v never read it but people get all exited about it it seems. >The author used to post here...The foul morons have driven a lot of people away.
Reply by ●March 16, 20232023-03-16
On Thu, 16 Mar 2023 05:06:35 -0700 (PDT), Fred Bloggs <bloggs.fredbloggs.fred@gmail.com> wrote:>On Wednesday, March 15, 2023 at 3:00:19?PM UTC-4, John Robertson wrote: >> I'm updating some game board designs and was curious if there is any >> sort of printed guideline for replacing silicon driver transistors with >> MOS? Both NPN and PNP. >> >> For example TIP122 Darlington transistors driven by another pre-driver, >> that is the TTL interface. I've seen many a substitute, but would like >> to have the theory explained so I can make better use of it and >> understand exactly what I am doing. >> >> A good reference book you can recommend perhaps? Books and I usually get >> along very well. >> >> Too many projects and not enough to hunt down all the solutions! > >Unless there's an availability problem with the bipolar, leave it. As far as any rules of thumb: don't touch a hot case with your bare thumb. > >> >> Thanks, and sorry for the on-topic post... > >You're one of these whiners always complaining about the group content, while contributing little to nothing yourself. >Never miss the opportunity to redirect a technical thread to an insult fest.
