Seeking switch debouncing circuit

[Charles L]

Can someone suggest or point me to a simple switch debouncing circuit for a
Single Pole Double Throw Switch using an S-R latch? I am quite new to this
and haven't been able to find a circuit anywhere.

Thanks in advance.

Charles L

 

[amstereo - matt2]

a small value cap over the switch contacts aparently works
"Charles L" <tjf00@dodo.com.au> wrote in message
news:3fb4c9fc$1@news.comindico.com.au...

Can someone suggest or point me to a simple switch debouncing circuit for
a
Single Pole Double Throw Switch using an S-R latch? I am quite new to this
and haven't been able to find a circuit anywhere.

Thanks in advance.

Charles L

 

[Ken Taylor]

"Charles L" <tjf00@dodo.com.au> wrote in message
news:3fb4c9fc$1@news.comindico.com.au...

Can someone suggest or point me to a simple switch debouncing circuit for
a
Single Pole Double Throw Switch using an S-R latch? I am quite new to this
and haven't been able to find a circuit anywhere.

Thanks in advance.

Charles L

The common of the switch goes to ground (or pulled to Vcc, depending on the

requirements of the S-R latch). The contacts then go to the Set and Reset
inputs. The 'switch' output is then the output of the latch, either the Q or
/Q, depending on what you want. Tie the Set and Reset to the appropriate
rail so that they don't float to the 'switch' condition.

With this, when you switch to one side, you will Set the latch, and it
doesn't matter if it bounces, the output remains stable. Ditto when you
switch the other way.

Ken

 

[KLR]

On Fri, 14 Nov 2003 23:24:20 +1000, "amstereo - matt2"
<amstereo@optusINTERnetDOT.comDOT.auSTRALIA> wrote:

a small value cap over the switch contacts aparently works
"Charles L" <tjf00@dodo.com.au> wrote in message
news:3fb4c9fc$1@news.comindico.com.au...
Can someone suggest or point me to a simple switch debouncing circuit for
a
Single Pole Double Throw Switch using an S-R latch? I am quite new to this
and haven't been able to find a circuit anywhere.

Thanks in advance.

Charles L




Tried that many years ago. It doesnt.

I recall using a 555 in one-shot mode to solve this problem at the
time/

 

[bruce varley]

Charles L <tjf00@dodo.com.au> wrote in message
news:3fb4c9fc$1@news.comindico.com.au...

Can someone suggest or point me to a simple switch debouncing circuit for
a
Single Pole Double Throw Switch using an S-R latch? I am quite new to this
and haven't been able to find a circuit anywhere.

Thanks in advance.

Charles L

A common an effective aproach is to connect 2 2-input nand gates as a RS

flipflop, which is maybe what you're thinking of.....

OP1 -> IP2a
OP2 -> IP1a

IP1b, IP2b both have a pullup to Vcc (about 4K7), and each goes to one side
of the SPDT switch. The common of the switch goes to ground.

 

[Steve]

Googled "s r latch debounce" and got

http://www.ee.nmt.edu/~wamageed/EE231-Fall03/Fall-03-Lab/lab07/lab07.html