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npn and pnp definitions

ArchiverArchiver Posts: 46,084
edited 2002-06-08 12:51 in General Discussion
Another newbie question...

Can someone define for me the meanings of and diferences between npn
and pnp related to mosfet transitors? Thanks.

Scott

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 18:42
    a n channel fet or mosfet acts like a npn transitor. a p channel fet or
    mosfet acts like a pnp transistor. bipolar transistors have thier parts
    labled emiter, colector, and base, the fets will have ther corasponding
    parts labeled source, drain, and gate, keep in mind that a biplar transistor
    (npn, pnp) are curent controled switch and that fets are vlotage controled
    so you will ether nead pull up of pull down risistors. a fet's gate is vary
    sensitive to damage from static discharge. id you will be switching
    inductive loads, ie: relays, motors you will nead a protection diode across
    the fet, most of the power fets that i use have protection diodes built in
    to them.

    hope this helps
    Lincoln


    > Can someone define for me the meanings of and diferences between npn
    > and pnp related to mosfet transitors? Thanks.
    >
    > Scott
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 18:51
    As far as controlling the device your statement is correct.
    However the behavior of a mosfet is much different than that of
    a transistor and can make a BIG difference depending on the
    circuit design. A mosfet is considered a resistive element,
    where a bipolar transistor exhibits characteristics of a diode.



    >a n channel fet or mosfet acts like a npn transitor. a p channel fet or
    >mosfet acts like a pnp transistor. bipolar transistors have thier parts
    >labled emiter, colector, and base, the fets will have ther corasponding
    >parts labeled source, drain, and gate, keep in mind that a biplar transistor
    >(npn, pnp) are curent controled switch and that fets are vlotage controled
    >so you will ether nead pull up of pull down risistors. a fet's gate is vary
    >sensitive to damage from static discharge. id you will be switching
    >inductive loads, ie: relays, motors you will nead a protection diode across
    >the fet, most of the power fets that i use have protection diodes built in
    >to them.
    >
    >hope this helps
    >Lincoln
    >
    >
    > > Can someone define for me the meanings of and diferences between npn
    > > and pnp related to mosfet transitors? Thanks.
    > >
    > > Scott
    > >

    Beau Schwabe Mask Designer IV - ATL
    National Semiconductor Enterprise Networking Business Unit
    500 Pinnacle Court, Suite 525 Wired Communications Division
    Mail Stop GA1 Norcross, GA 30071
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 19:03
    If I'd been smarter (who is when they're young and in college), I'd have
    taken more circuits courses when I was in my aero engineering program.
    Aside from that, is there anything out there that explains transistors and
    MOSFETs in english, but in more than just elementary school terms?
    Don
    Original Message
    From: "Beau Schwabe" <bschwabe@a...>
    To: <basicstamps@yahoogroups.com>
    Sent: Friday, June 07, 2002 10:51 AM
    Subject: Re: [noparse][[/noparse]basicstamps] npn and pnp definitions


    > As far as controlling the device your statement is correct.
    > However the behavior of a mosfet is much different than that of
    > a transistor and can make a BIG difference depending on the
    > circuit design. A mosfet is considered a resistive element,
    > where a bipolar transistor exhibits characteristics of a diode.
    >
    >
    >
    > >a n channel fet or mosfet acts like a npn transitor. a p channel fet or
    > >mosfet acts like a pnp transistor. bipolar transistors have thier parts
    > >labled emiter, colector, and base, the fets will have ther corasponding
    > >parts labeled source, drain, and gate, keep in mind that a biplar
    transistor
    > >(npn, pnp) are curent controled switch and that fets are vlotage
    controled
    > >so you will ether nead pull up of pull down risistors. a fet's gate is
    vary
    > >sensitive to damage from static discharge. id you will be switching
    > >inductive loads, ie: relays, motors you will nead a protection diode
    across
    > >the fet, most of the power fets that i use have protection diodes built
    in
    > >to them.
    > >
    > >hope this helps
    > >Lincoln
    > >
    > >
    > > > Can someone define for me the meanings of and diferences between npn
    > > > and pnp related to mosfet transitors? Thanks.
    > > >
    > > > Scott
    > > >
    >
    >
    > Beau Schwabe Mask Designer IV - ATL
    > National Semiconductor Enterprise Networking Business Unit
    > 500 Pinnacle Court, Suite 525 Wired Communications Division
    > Mail Stop GA1 Norcross, GA 30071
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 19:09
    Don,
    I would highly recommend The Art of Electronics by Horowitz and Hill. I
    find it on the shelf of most of the biology graduate students who want to
    understand electronics without having to take an engineering course.
    Mike


    At 11:03 AM 6/7/2002 -0700, you wrote:
    >, is there anything out there that explains transistors and
    >MOSFETs in english, but in more than just elementary school terms?

    _________________________________
    Mike Walsh
    walsh@i...


    [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 19:56
    This might be a good start:

    http://ece-www.colorado.edu/~bart/book/book/append/append1.htm


    > If I'd been smarter (who is when they're young and in college), I'd have
    >taken more circuits courses when I was in my aero engineering program.
    >Aside from that, is there anything out there that explains transistors and
    >MOSFETs in english, but in more than just elementary school terms?
    >Don
    >
    Original Message
    >From: "Beau Schwabe" <bschwabe@a...>
    >To: <basicstamps@yahoogroups.com>
    >Sent: Friday, June 07, 2002 10:51 AM
    >Subject: Re: [noparse][[/noparse]basicstamps] npn and pnp definitions
    >
    >
    > > As far as controlling the device your statement is correct.
    > > However the behavior of a mosfet is much different than that of
    > > a transistor and can make a BIG difference depending on the
    > > circuit design. A mosfet is considered a resistive element,
    > > where a bipolar transistor exhibits characteristics of a diode.
    > >
    > >
    > >
    > > >a n channel fet or mosfet acts like a npn transitor. a p channel fet or
    > > >mosfet acts like a pnp transistor. bipolar transistors have thier parts
    > > >labled emiter, colector, and base, the fets will have ther corasponding
    > > >parts labeled source, drain, and gate, keep in mind that a biplar
    >transistor
    > > >(npn, pnp) are curent controled switch and that fets are vlotage
    >controled
    > > >so you will ether nead pull up of pull down risistors. a fet's gate is
    >vary
    > > >sensitive to damage from static discharge. id you will be switching
    > > >inductive loads, ie: relays, motors you will nead a protection diode
    >across
    > > >the fet, most of the power fets that i use have protection diodes built
    >in
    > > >to them.
    > > >
    > > >hope this helps
    > > >Lincoln
    > > >
    > > >
    > > > > Can someone define for me the meanings of and diferences between npn
    > > > > and pnp related to mosfet transitors? Thanks.
    > > > >
    > > > > Scott
    > > > >
    > >
    > >
    > > Beau Schwabe Mask Designer IV - ATL
    > > National Semiconductor Enterprise Networking Business Unit
    > > 500 Pinnacle Court, Suite 525 Wired Communications Division
    > > Mail Stop GA1 Norcross, GA 30071
    > >
    > >
    > >
    > >
    > > To UNSUBSCRIBE, just send mail to:
    > > basicstamps-unsubscribe@yahoogroups.com
    > > from the same email address that you subscribed. Text in the Subject and
    >Body of the message will be ignored.
    > >
    > >
    > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    > >
    > >
    > >
    >
    >
    >
    >To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    >from the same email address that you subscribed. Text in the Subject and
    >Body of the message will be ignored.
    >
    >
    >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

    Beau Schwabe Mask Designer IV - ATL
    National Semiconductor Enterprise Networking Business Unit
    500 Pinnacle Court, Suite 525 Wired Communications Division
    Mail Stop GA1 Norcross, GA 30071
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 20:09
    Cool, Thanks. I found the table of contents and bookmarked it. I'll
    start through it later.
    Don
    Original Message
    From: "Beau Schwabe" <bschwabe@a...>
    To: <basicstamps@yahoogroups.com>
    Sent: Friday, June 07, 2002 11:56 AM
    Subject: Re: [noparse][[/noparse]basicstamps] npn and pnp definitions


    > This might be a good start:
    >
    > http://ece-www.colorado.edu/~bart/book/book/append/append1.htm
    >
    >
    > > If I'd been smarter (who is when they're young and in college), I'd
    have
    > >taken more circuits courses when I was in my aero engineering program.
    > >Aside from that, is there anything out there that explains transistors
    and
    > >MOSFETs in english, but in more than just elementary school terms?
    > >Don
    > >
    Original Message
    > >From: "Beau Schwabe" <bschwabe@a...>
    > >To: <basicstamps@yahoogroups.com>
    > >Sent: Friday, June 07, 2002 10:51 AM
    > >Subject: Re: [noparse][[/noparse]basicstamps] npn and pnp definitions
    > >
    > >
    > > > As far as controlling the device your statement is correct.
    > > > However the behavior of a mosfet is much different than that of
    > > > a transistor and can make a BIG difference depending on the
    > > > circuit design. A mosfet is considered a resistive element,
    > > > where a bipolar transistor exhibits characteristics of a diode.
    > > >
    > > >
    > > >
    > > > >a n channel fet or mosfet acts like a npn transitor. a p channel fet
    or
    > > > >mosfet acts like a pnp transistor. bipolar transistors have thier
    parts
    > > > >labled emiter, colector, and base, the fets will have ther
    corasponding
    > > > >parts labeled source, drain, and gate, keep in mind that a biplar
    > >transistor
    > > > >(npn, pnp) are curent controled switch and that fets are vlotage
    > >controled
    > > > >so you will ether nead pull up of pull down risistors. a fet's gate
    is
    > >vary
    > > > >sensitive to damage from static discharge. id you will be switching
    > > > >inductive loads, ie: relays, motors you will nead a protection diode
    > >across
    > > > >the fet, most of the power fets that i use have protection diodes
    built
    > >in
    > > > >to them.
    > > > >
    > > > >hope this helps
    > > > >Lincoln
    > > > >
    > > > >
    > > > > > Can someone define for me the meanings of and diferences between
    npn
    > > > > > and pnp related to mosfet transitors? Thanks.
    > > > > >
    > > > > > Scott
    > > > > >
    > > >
    > > >
    > > > Beau Schwabe Mask Designer IV - ATL
    > > > National Semiconductor Enterprise Networking Business Unit
    > > > 500 Pinnacle Court, Suite 525 Wired Communications Division
    > > > Mail Stop GA1 Norcross, GA 30071
    > > >
    > > >
    > > >
    > > >
    > > > To UNSUBSCRIBE, just send mail to:
    > > > basicstamps-unsubscribe@yahoogroups.com
    > > > from the same email address that you subscribed. Text in the Subject
    and
    > >Body of the message will be ignored.
    > > >
    > > >
    > > > Your use of Yahoo! Groups is subject to
    http://docs.yahoo.com/info/terms/
    > > >
    > > >
    > > >
    > >
    > >
    > >
    > >To UNSUBSCRIBE, just send mail to:
    > > basicstamps-unsubscribe@yahoogroups.com
    > >from the same email address that you subscribed. Text in the Subject and
    > >Body of the message will be ignored.
    > >
    > >
    > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    > Beau Schwabe Mask Designer IV - ATL
    > National Semiconductor Enterprise Networking Business Unit
    > 500 Pinnacle Court, Suite 525 Wired Communications Division
    > Mail Stop GA1 Norcross, GA 30071
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 21:29
    Hi Don,

    I can thoroughly recommend the following book: -
    Horowitz & Hill, The Art of Electronics.
    Covers most electronic subjects in easy to understand detail. My copy is
    falling apart at the seams, 25 years in the electronics industry and I
    still refer to it at least once a week.

    Rob

    Original Message
    From: Don [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=9OI0b-k0MKIRVrhW2nfp4Ie8UZFO2of68_qOIDBjisr6jVaAr_gcBiv6-yp1BNJbAM9pDgpW0tsDq1965ZVATIn62Q]renegade.engineer@v...[/url
    Sent: 07 June 2002 19:03
    To: basicstamps@yahoogroups.com
    Subject: Re: [noparse][[/noparse]basicstamps] npn and pnp definitions

    If I'd been smarter (who is when they're young and in college), I'd
    have
    taken more circuits courses when I was in my aero engineering program.
    Aside from that, is there anything out there that explains transistors
    and
    MOSFETs in english, but in more than just elementary school terms?
    Don
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 21:37
    Just seen Mike Walsh's simultaneous post re: Horowitz & Hill The Art of
    electronics.
    Shows what an excellent Book it is.

    Rob

    Original Message
    From: Rob [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=yekAaWJtpzezC0srmIr4AbabfqDSurmczDqUxyw2rx_VEc5C8RxqXhkgZod3VodKRPdfNIRiQAogr0v2LnDToiU]robbed666@b...[/url
    Sent: 07 June 2002 21:30
    To: basicstamps@yahoogroups.com
    Subject: RE: [noparse][[/noparse]basicstamps] npn and pnp definitions

    Hi Don,

    I can thoroughly recommend the following book: -
    Horowitz & Hill, The Art of Electronics.
    Covers most electronic subjects in easy to understand detail. My copy is
    falling apart at the seams, 25 years in the electronics industry and I
    still refer to it at least once a week.

    Rob
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-07 22:02
    Yes it looks good! I'm going to look at the 'free' online book that
    Beau sent a bookmark for, and then I'll probably get a copy of the Horowitz
    and Hill book later.
    Thanks to both you and Mike!
    Don
    Original Message
    From: "Rob" <robbed666@b...>
    To: <basicstamps@yahoogroups.com>
    Sent: Friday, June 07, 2002 1:37 PM
    Subject: RE: [noparse][[/noparse]basicstamps] npn and pnp definitions


    > Just seen Mike Walsh's simultaneous post re: Horowitz & Hill The Art of
    > electronics.
    > Shows what an excellent Book it is.
    >
    > Rob
    >
    >
    Original Message
    > From: Rob [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=u_CeCgVOrx0mpdH5jDVPTZZ2Oz1qSh2EkTj7De3ORA1sg2C5-_egOwj6Tpj-7iiAkQpbOAwInJf0uTrGhE2xJN4]robbed666@b...[/url
    > Sent: 07 June 2002 21:30
    > To: basicstamps@yahoogroups.com
    > Subject: RE: [noparse][[/noparse]basicstamps] npn and pnp definitions
    >
    > Hi Don,
    >
    > I can thoroughly recommend the following book: -
    > Horowitz & Hill, The Art of Electronics.
    > Covers most electronic subjects in easy to understand detail. My copy is
    > falling apart at the seams, 25 years in the electronics industry and I
    > still refer to it at least once a week.
    >
    > Rob
    >
    >
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
    > basicstamps-unsubscribe@yahoogroups.com
    > from the same email address that you subscribed. Text in the Subject and
    Body of the message will be ignored.
    >
    >
    > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-08 03:09
    Dear Don,

    When I taught Industrial Electronics at the local vocational school, one
    of my primary objectives was to show the students how transistors work.
    We were not concerned with physics and hole flow and all that
    engineering stuff, We wanted to learn just enough to repair the the
    device if it was in working circuit and for some reason stopped
    working. Here are some of the things I stressed:

    Current flow is made up of electrons and they from negative to positive

    An NPN transistor is an amplifier for current, that is a small controls
    current (Ib) -- controls a larger current (Ic).

    An NPN transistor has three currents emitter, collector, and base
    current. The relation ship between the three is emitter current equals
    base current plus collector current.

    The device has a gain which we called beta. Beta equals base current
    times collector current. Or beta = Ib * Ic If a transistor has a beta
    of 200 this means the base current is 1/200 of the collector current.
    Obviously the higher the beta - the higher the input impedance and the
    better the device performed in the circuit.

    To associate an NPN transistor with it's schematic symbol we said it had
    NOT POINTED IN POINTER. A PNP had a POINTED IN POINTER. Kinda simple,
    but it works.

    Current directions: for an NPN device the base current would enter the
    device at the emitter and exit at the base. This was the control
    current. Collector current would also enter at emitter and exit at the
    collector. This was the controlled current.

    There are several more points but they involve resistors outside the
    device and what percent of the supply voltages was placed at what points
    in the circuit. i.e. emitter voltage is usually 10% of the supply, base
    voltage is usually 1/2 the supply and is .7 volts more positive than the
    emitter. These are not rules by any means just general guidelines for a
    transistor operated as a class A amplifier.


    A PNP device works in a similar way, except the polarities and current
    flows are reversed.



    HTH,

    Leroy
  • ArchiverArchiver Posts: 46,084
    edited 2002-06-08 12:51
    For those who are interested, Bookpool.com has it for about $50. The other
    two major booksellers on the Net are selling it for list price, $70.00. I
    have no affiliation with any of them, I'm just a humble electrician looking
    to save a couple of bucks.... ;-}

    Tom

    Original Message
    > Date: Fri, 7 Jun 2002 21:29:59 +0100
    >From: "Rob" <robbed666@b...>
    >Subject: RE: npn and pnp definitions

    >Hi Don,

    >I can thoroughly recommend the following book: -
    >Horowitz & Hill, The Art of Electronics.
    >Covers most electronic subjects in easy to understand detail. My copy is
    >falling apart at the seams, 25 years in the electronics industry and I
    >still refer to it at least once a week.

    >Rob

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