unknown electrical symbol
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Posts: 46,084
Hi:
I have a question for everyone; I am looking at a functional block digram for a
mosfet driver and I notice they use a symbol that I am not familliar with. The
symbol looks like an opamp (triangle with a "+" and "-" on its input) but on the
lower side of the triangle there is a little dot which touches but does not go
into the triangle of the opamp. A wire is connecting this dot to a NAND gate I
was wondering what this means?
Thanks!
-=Randy Knutson
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[noparse][[/noparse]Non-text portions of this message have been removed]
I have a question for everyone; I am looking at a functional block digram for a
mosfet driver and I notice they use a symbol that I am not familliar with. The
symbol looks like an opamp (triangle with a "+" and "-" on its input) but on the
lower side of the triangle there is a little dot which touches but does not go
into the triangle of the opamp. A wire is connecting this dot to a NAND gate I
was wondering what this means?
Thanks!
-=Randy Knutson
Do You Yahoo!?
Sign-up for Video Highlights of 2002 FIFA World Cup
[noparse][[/noparse]Non-text portions of this message have been removed]
Comments
My guess is that it's an input that, when brought low will put the OP-amps
outputstage in high impedance. Almost like shutting it down.
/Henrik Olsson.
Original Message
From: "Randy Knutson" <ken_ryder@y...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, June 20, 2002 6:59 PM
Subject: [noparse][[/noparse]basicstamps] unknown electrical symbol
>
> Hi:
> I have a question for everyone; I am looking at a functional block digram
for a mosfet driver and I notice they use a symbol that I am not familliar
with. The symbol looks like an opamp (triangle with a "+" and "-" on its
input) but on the lower side of the triangle there is a little dot which
touches but does not go into the triangle of the opamp. A wire is connecting
this dot to a NAND gate I was wondering what this means?
> Thanks!
> -=Randy Knutson
>
>
>
>
> Do You Yahoo!?
> Sign-up for Video Highlights of 2002 FIFA World Cup
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
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>
>I have a question for everyone; I am looking at a functional block
>digram for a mosfet driver and I notice they use a symbol that I am
>not familliar with. The symbol looks like an opamp (triangle with a
>"+" and "-" on its input) but on the lower side of the triangle
>there is a little dot which touches but does not go into the
>triangle of the opamp. A wire is connecting this dot to a NAND gate
>I was wondering what this means?
>Thanks!
>-=Randy Knutson
That may mean "tri-state". The chip is probably a comparator, not an
op-amp. The output is then high when (+) input > (-) input, or low
when (-) input > (+) input, or the output can be in a third state, an
open circuit essentially disconnected when the tri-state input (the
dot connected to the NAND gate) is asserted.
Logic high, logic low, and Hi-Z (impedence) which is the logic level the dot
is in reference to. In this state the device is effectively "detached" from
the circuit bus.