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How many ULN2803 outputs can I use? — Parallax Forums

How many ULN2803 outputs can I use?

ArchiverArchiver Posts: 46,084
edited 2004-05-25 07:38 in General Discussion
I am hooking up the ULN2803 transistor array directly to the BS2 to
run realys. How many pins can I keep on at the same time. I need at
lease 3 realys to stay for around 5 minutes. Would this be too much
for the stamp to handle? Would it be better to use the BS2e?
Do I need to hook up the +ve pin on the ULN2803?
thanks
Basil

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-05-25 06:34
    --- In basicstamps@yahoogroups.com, "basilmelbourne"
    <basilmelbourne@y...> wrote:
    > I am hooking up the ULN2803 transistor array directly to the BS2 to
    > run realys. How many pins can I keep on at the same time. I need at
    > lease 3 realys to stay for around 5 minutes. Would this be too much
    > for the stamp to handle? Would it be better to use the BS2e?
    > Do I need to hook up the +ve pin on the ULN2803?
    > thanks
    > Basil

    Check out the relays.

    The main thing is that the CDIP package cannot shed more than a
    certain amount of heat.

    I think the data sheet says 500mA per channel, but the case maxes out
    at like 350mA per channel if all the channels are driver at the same
    time.

    If you have a need for only 3 relays, and they are high power,
    considder a simple TIP123 darlington in a 220 case, I think it is
    good for about 5 amps continuous with a heat sink.

    Regardless of your transitor, the Stamp would only be sending a very
    low current signal to it. IIRC, the outputs on the 2e are not higher
    current than the BS2, If I am wrong, I certanily will hear about it !

    If you wanted to use a couple dozen outputs you have lots of
    choices. the 74hc595 can use 4 pins of the Stamp and control 8
    output channels. or 2 595's can use still only 4 stamp pins and 16
    outputs.. or ten 595's will only use the same 4 pins and handle 80
    outputs.

    Just wanted to make sure I answered the subject line in all the ways
    it might be read.

    Dave
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-25 07:03
    Interesting.. Anyone have a pinout of how to use multiple 74hc595 (lets say
    4) to interface with a BS2-ic module?

    This might be a better solution.. As I am running out of I/O pins
    thanks-Lee


    Original Message
    From: "Dave Mucha" <davemucha@j...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, May 25, 2004 1:34 AM
    Subject: [noparse][[/noparse]basicstamps] Re: How many ULN2803 outputs can I use?


    > --- In basicstamps@yahoogroups.com, "basilmelbourne"
    > <basilmelbourne@y...> wrote:
    > > I am hooking up the ULN2803 transistor array directly to the BS2 to
    > > run realys. How many pins can I keep on at the same time. I need at
    > > lease 3 realys to stay for around 5 minutes. Would this be too much
    > > for the stamp to handle? Would it be better to use the BS2e?
    > > Do I need to hook up the +ve pin on the ULN2803?
    > > thanks
    > > Basil
    >
    > Check out the relays.
    >
    > The main thing is that the CDIP package cannot shed more than a
    > certain amount of heat.
    >
    > I think the data sheet says 500mA per channel, but the case maxes out
    > at like 350mA per channel if all the channels are driver at the same
    > time.
    >
    > If you have a need for only 3 relays, and they are high power,
    > considder a simple TIP123 darlington in a 220 case, I think it is
    > good for about 5 amps continuous with a heat sink.
    >
    > Regardless of your transitor, the Stamp would only be sending a very
    > low current signal to it. IIRC, the outputs on the 2e are not higher
    > current than the BS2, If I am wrong, I certanily will hear about it !
    >
    > If you wanted to use a couple dozen outputs you have lots of
    > choices. the 74hc595 can use 4 pins of the Stamp and control 8
    > output channels. or 2 595's can use still only 4 stamp pins and 16
    > outputs.. or ten 595's will only use the same 4 pins and handle 80
    > outputs.
    >
    > Just wanted to make sure I answered the subject line in all the ways
    > it might be read.
    >
    > Dave
    >
    >
    >
    >
    >
    > 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.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-25 07:08
    http://www.parallax.com/dl/docs/books/sw/exp/sw23a.pdf
    This might help

    -John Baker
    Trend <fredit@c...> wrote:
    Interesting.. Anyone have a pinout of how to use multiple 74hc595 (lets say
    4) to interface with a BS2-ic module?

    This might be a better solution.. As I am running out of I/O pins
    thanks-Lee


    Original Message
    From: "Dave Mucha"
    To:
    Sent: Tuesday, May 25, 2004 1:34 AM
    Subject: [noparse][[/noparse]basicstamps] Re: How many ULN2803 outputs can I use?


    > --- In basicstamps@yahoogroups.com, "basilmelbourne"
    > wrote:
    > > I am hooking up the ULN2803 transistor array directly to the BS2 to
    > > run realys. How many pins can I keep on at the same time. I need at
    > > lease 3 realys to stay for around 5 minutes. Would this be too much
    > > for the stamp to handle? Would it be better to use the BS2e?
    > > Do I need to hook up the +ve pin on the ULN2803?
    > > thanks
    > > Basil
    >
    > Check out the relays.
    >
    > The main thing is that the CDIP package cannot shed more than a
    > certain amount of heat.
    >
    > I think the data sheet says 500mA per channel, but the case maxes out
    > at like 350mA per channel if all the channels are driver at the same
    > time.
    >
    > If you have a need for only 3 relays, and they are high power,
    > considder a simple TIP123 darlington in a 220 case, I think it is
    > good for about 5 amps continuous with a heat sink.
    >
    > Regardless of your transitor, the Stamp would only be sending a very
    > low current signal to it. IIRC, the outputs on the 2e are not higher
    > current than the BS2, If I am wrong, I certanily will hear about it !
    >
    > If you wanted to use a couple dozen outputs you have lots of
    > choices. the 74hc595 can use 4 pins of the Stamp and control 8
    > output channels. or 2 595's can use still only 4 stamp pins and 16
    > outputs.. or ten 595's will only use the same 4 pins and handle 80
    > outputs.
    >
    > Just wanted to make sure I answered the subject line in all the ways
    > it might be read.
    >
    > Dave
    >
    >
    >
    >
    >
    > 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.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >




    To UNSUBSCRIBE, just send mail to:
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  • ArchiverArchiver Posts: 46,084
    edited 2004-05-25 07:38
    Thanks, I downloaded that to my BS2 folder [noparse]:)[/noparse]
    Lee


    Original Message
    From: "John Baker" <johnbaker_erie_pa@y...>
    To: <basicstamps@yahoogroups.com>
    Sent: Tuesday, May 25, 2004 2:08 AM
    Subject: Re: [noparse][[/noparse]basicstamps] Re: How many ULN2803 outputs can I use?


    >
    > http://www.parallax.com/dl/docs/books/sw/exp/sw23a.pdf
    > This might help
    >
    > -John Baker
    > Trend <fredit@c...> wrote:
    > Interesting.. Anyone have a pinout of how to use multiple 74hc595 (lets
    say
    > 4) to interface with a BS2-ic module?
    >
    > This might be a better solution.. As I am running out of I/O pins
    > thanks-Lee
    >
    >
    >
    Original Message
    > From: "Dave Mucha"
    > To:
    > Sent: Tuesday, May 25, 2004 1:34 AM
    > Subject: [noparse][[/noparse]basicstamps] Re: How many ULN2803 outputs can I use?
    >
    >
    > > --- In basicstamps@yahoogroups.com, "basilmelbourne"
    > > wrote:
    > > > I am hooking up the ULN2803 transistor array directly to the BS2 to
    > > > run realys. How many pins can I keep on at the same time. I need at
    > > > lease 3 realys to stay for around 5 minutes. Would this be too much
    > > > for the stamp to handle? Would it be better to use the BS2e?
    > > > Do I need to hook up the +ve pin on the ULN2803?
    > > > thanks
    > > > Basil
    > >
    > > Check out the relays.
    > >
    > > The main thing is that the CDIP package cannot shed more than a
    > > certain amount of heat.
    > >
    > > I think the data sheet says 500mA per channel, but the case maxes out
    > > at like 350mA per channel if all the channels are driver at the same
    > > time.
    > >
    > > If you have a need for only 3 relays, and they are high power,
    > > considder a simple TIP123 darlington in a 220 case, I think it is
    > > good for about 5 amps continuous with a heat sink.
    > >
    > > Regardless of your transitor, the Stamp would only be sending a very
    > > low current signal to it. IIRC, the outputs on the 2e are not higher
    > > current than the BS2, If I am wrong, I certanily will hear about it !
    > >
    > > If you wanted to use a couple dozen outputs you have lots of
    > > choices. the 74hc595 can use 4 pins of the Stamp and control 8
    > > output channels. or 2 595's can use still only 4 stamp pins and 16
    > > outputs.. or ten 595's will only use the same 4 pins and handle 80
    > > outputs.
    > >
    > > Just wanted to make sure I answered the subject line in all the ways
    > > it might be read.
    > >
    > > Dave
    > >
    > >
    > >
    > >
    > >
    > > 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.
    > >
    > > Yahoo! Groups Links
    > >
    > >
    > >
    > >
    > >
    >
    >
    >
    >
    > 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.
    >
    > Yahoo! Groups Links
    >
    >
    >
    >
    >
    > __________________________________________________
    > Do You Yahoo!?
    > Tired of spam? Yahoo! Mail has the best spam protection around
    > http://mail.yahoo.com
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
    >
    >
    >
    > To UNSUBSCRIBE, just send mail to:
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