Dedicated debouncer IC...

[server]

On Wed, 12 Aug 2020 11:15:33 +0100, Andy Bennet <andyb@andy.com>
wrote:

On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal 6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

Change the switch to SPDT, earth the centre and use 2 pullups with
cross coupled nands as a set reset FF. Instant action, no bounce.

Some flops can be forced at their outputs, so just ground Q or Qbar
with an SPDT switch.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[Joe Chisolm]

On Wed, 12 Aug 2020 08:43:47 -0700, jlarkin wrote:

On Wed, 12 Aug 2020 15:54:16 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 2:53 PM, TTman wrote:
On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal
6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

I used a maxim reset chip.... if you can live with the 140mS odd
delay..
No doubt Microchip do something similar....

Examples?

The MAX809 series has all sorts of uses. The best part is that you don\'t
have to buy them from Maxim.

But as a debouncer, you\'d need more parts. Some other POR chips might
not.

A Schmitt gate would need an RC per switch, which could be in quad
packs.

Why do you need to debounce?

Thanks for the 809. I\'ve used TI and ST parts as debounce but
both needed a pull down from vcc to be reliable.

--
Chisolm
Texas-American

 

[bitrex]

On 8/12/2020 6:50 AM, Jan Panteltje wrote:

On a sunny day (Wed, 12 Aug 2020 10:27:31 +0100) it happened Tom Gardner
spamjunk@blueyonder.co.uk> wrote in <7COYG.919245$wVe.260011@fx47.ams4>:

On 12/08/20 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite pricey at
$1 for the single MAX6816 and several $$ for the octal 6818. Are there any
cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally simple
devices that have pins for each mechanical switch and for the debounced output.
Nothing else apart from Vcc and ground. The 40ms debouncing is done internally
without any external component.

It pains me to note...
https://cpldcpu.wordpress.com/2019/08/12/the-terrible-3-cent-mcu/


https://cpldcpu.files.wordpress.com/2019/08/3-cent-mcu-1.png
Nice
I like the Padauk.

If it\'s got an 8 bit ADC you can debounce 5 or 6 button per port with
some averaging and a state machine.

 

[Pimpom]

On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:

On Wed, 12 Aug 2020 15:54:16 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 2:53 PM, TTman wrote:
On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal 6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

I used a maxim reset chip.... if you can live with the 140mS odd delay..
No doubt Microchip do something similar....

Examples?

The MAX809 series has all sorts of uses. The best part is that you
don\'t have to buy them from Maxim.

But as a debouncer, you\'d need more parts.

Exactly, and that\'s what I want to avoid. Otherwise there are a
number of ways to debounce using general-purpose parts.

Some other POR chips might not.

A Schmitt gate would need an RC per switch, which could be in quad
packs.

I\'ve used that and other techniques before.

Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock
standalone solution for future applications.

 

[Don Y]

On 8/12/2020 11:22 PM, Pimpom wrote:

On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock standalone solution
for future applications.

So, you\'re going to FIX the cost and capabilities of that \"solution\"
without concern for the needs of those \"future applications\"???

<shakes head>

 

[Klaus Kragelund]

On Thursday, August 13, 2020 at 8:22:30 AM UTC+2, Pimpom wrote:

On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
On Wed, 12 Aug 2020 15:54:16 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 2:53 PM, TTman wrote:
On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal 6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

I used a maxim reset chip.... if you can live with the 140mS odd delay..
No doubt Microchip do something similar....

Examples?

The MAX809 series has all sorts of uses. The best part is that you
don\'t have to buy them from Maxim.

But as a debouncer, you\'d need more parts.

Exactly, and that\'s what I want to avoid. Otherwise there are a
number of ways to debounce using general-purpose parts.

Some other POR chips might not.

A Schmitt gate would need an RC per switch, which could be in quad
packs.

I\'ve used that and other techniques before.

Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock
standalone solution for future applications.

Place the cheap micro, you will be able to use it for other stuff also

 

[Ricketty C]

On Wednesday, August 12, 2020 at 6:15:39 AM UTC-4, Andy Bennet wrote:

On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal 6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

Change the switch to SPDT, earth the centre and use 2 pullups with
cross coupled nands as a set reset FF. Instant action, no bounce.

What debounce doesn\'t have instant action? I guess there are some where the switch opens allowing an RC to rise which continues to get reset until it is done bouncing. The circuits I prefer follow the initial transition of the switch but lock out subsequent transitions until a time out. Best when done digitally in a single part of course. Analog solutions tend to be messy and have wide variations.

Heck, the switches themselves are best replaced with something else. Switches suck!

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[whit3rd]

On Wednesday, August 12, 2020 at 1:56:41 AM UTC-7, Pimpom wrote:

The MAX681* series of switch debouncers look useful but they\'re
quite pricey at >$1 for the single MAX6816 and several $$ for the
octal 6818. Are there any cheaper, easily available alternatives?

It\'s possible to get resistor arrays for pullups, so the main \'debounce\'
requirement is just a bit of latching. Octal edge-triggered latches,
with a 440 Hz (concert A pitch) clock, will get you eight debounced
outputs with one 10-pin SIP pullup and a 74xC573, for under $0.10
per circuit. The clock, though, is an extra overhead.

 

[Michael Kellett]

On 13/08/2020 08:30, Klaus Kragelund wrote:

On Thursday, August 13, 2020 at 8:22:30 AM UTC+2, Pimpom wrote:
On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
On Wed, 12 Aug 2020 15:54:16 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 2:53 PM, TTman wrote:
On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal 6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

I used a maxim reset chip.... if you can live with the 140mS odd delay..
No doubt Microchip do something similar....

Examples?

The MAX809 series has all sorts of uses. The best part is that you
don\'t have to buy them from Maxim.

But as a debouncer, you\'d need more parts.

Exactly, and that\'s what I want to avoid. Otherwise there are a
number of ways to debounce using general-purpose parts.

Some other POR chips might not.

A Schmitt gate would need an RC per switch, which could be in quad
packs.

I\'ve used that and other techniques before.

Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock
standalone solution for future applications.

Place the cheap micro, you will be able to use it for other stuff also

Agreed, unless its for quite high volumes there is no point arguing a $1
micro against a free chip with extra parts for a \"stock\" solution.

There are 8 bit PICs and AVRs at under £0.5 and ARMs at under £0.75 in
small numbers from Farnell.

MK

 

[Phil Hobbs]

On 2020-08-13 03:48, Michael Kellett wrote:

On 13/08/2020 08:30, Klaus Kragelund wrote:
On Thursday, August 13, 2020 at 8:22:30 AM UTC+2, Pimpom wrote:
On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
On Wed, 12 Aug 2020 15:54:16 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 2:53 PM, TTman wrote:
On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re
quite
pricey at >$1 for the single MAX6816 and several $$ for the octal
6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

I used a maxim reset chip.... if you can live with the 140mS odd
delay..
No doubt Microchip do something similar....

Examples?

The MAX809 series has all sorts of uses. The best part is that you
don\'t have to buy them from Maxim.

But as a debouncer, you\'d need more parts.

Exactly, and that\'s what I want to avoid. Otherwise there are a
number of ways to debounce using general-purpose parts.

Some other POR chips might not.

A Schmitt gate would need an RC per switch, which could be in quad
packs.

I\'ve used that and other techniques before.

Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock
standalone solution for future applications.

Place the cheap micro, you will be able to use it for other stuff also

Agreed, unless its for quite high volumes there is no point arguing a $1
micro against a free chip with extra parts for a \"stock\" solution.

There are 8 bit PICs and AVRs at under £0.5 and ARMs at under £0.75 in
small numbers from Farnell.

MK

For hobby-style products, there\'s a certain beauty in the three-cent
Padauk gizmo, particularly since it\'s from Taiwan, which (so far) is
outside the grasp of the CCP.

Squeaky Dave has a series of videos about how to get the open-source
hardware and SDCC (\"small device C compiler\") toolchain working with the
Padauk micros. A nice example of a community effort, for sure.

https://www.youtube.com/watch?v=4fvFLSeDc4M

(Dave is a lot easier to take when run at 1.75x speed on Youtube.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Mike Coon]

In article <f4777b32-bd27-4de9-a193-33e548fb3b9do@googlegroups.com>,
gnuarm.deletethisbit@gmail.com says...

Heck, the switches themselves are best replaced with something else.
Switches suck!

I bet you prefer on-(touch)-screen keyboards for typing...

Mike.

 

[Tom Gardner]

On 13/08/20 08:59, Phil Hobbs wrote:
> (Dave is a lot easier to take when run at 1.75x speed on Youtube.)

2x, closed captions, speakers off

But then I dislike 99.9% of the electronics videos since
I can read articles much faster than they can speak.

 

[Pimpom]

On 8/13/2020 12:18 PM, Don Y wrote:

On 8/12/2020 11:22 PM, Pimpom wrote:
On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock standalone solution
for future applications.

So, you\'re going to FIX the cost and capabilities of that \"solution\"
without concern for the needs of those \"future applications\"???

shakes head

I don\'t understand the head shaking. Anyone who designs circuits
regularly will have their favourite solution for a common task.
I\'ve used various debouncing techniques but they all require
passive components, a particular type of switch, and in some
cases another active device to complement the main active devices.

If there\'s an inexpensive standalone part that needs no external
parts and can replace those techniques in most applications,
what\'s wrong with using that as a stock solution? A 2N3904/BC547
transistor can be used at the heart of a wide range of low
frequency low power applications. Why hunt for a suitable type
every time?

 

[Pimpom]

On 8/13/2020 2:42 PM, Tom Gardner wrote:

On 13/08/20 08:59, Phil Hobbs wrote:
(Dave is a lot easier to take when run at 1.75x speed on Youtube.)

2x, closed captions, speakers off

But then I dislike 99.9% of the electronics videos since
I can read articles much faster than they can speak.

+1 - as those kids in web forums are fond of saying.

 

[Don Y]

On 8/13/2020 2:43 AM, Pimpom wrote:

On 8/13/2020 12:18 PM, Don Y wrote:
On 8/12/2020 11:22 PM, Pimpom wrote:
On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock standalone solution
for future applications.

So, you\'re going to FIX the cost and capabilities of that \"solution\"
without concern for the needs of those \"future applications\"???

shakes head

I don\'t understand the head shaking. Anyone who designs circuits regularly will
have their favourite solution for a common task. I\'ve used various debouncing
techniques but they all require passive components, a particular type of
switch, and in some cases another active device to complement the main active
devices.

If there\'s an inexpensive standalone part that needs no external parts and can
replace those techniques in most applications, what\'s wrong with using that as
a stock solution? A 2N3904/BC547 transistor can be used at the heart of a wide
range of low frequency low power applications. Why hunt for a suitable type
every time?

What do you do when you need a greater Icc? Do you have your \"favorite FET\"?
\"Diode\"? \"Switch\"?

Do you use them regardless of what the *particular* requirements and
constraints of the design happen to be?

You should be reusing ideas, not implementations. So, for example, a
particular amplifier topology -- not a particular set of components to
implement that particular amplifier instance.

You develop a preference for a particular component when you find yourself
using it in many SIMILAR applications. But, that doesn\'t stop you from
reevaluating whether it is APPROPRIATE for a specific NEW application!
You risk limiting your solutions to embrace past experiences instead of
current needs.

(What do you do when you have to debounce 200 pushbuttons -- like on a
video switcher? Do you use the same components -- and techniques! -- that
you did when debouncing ONE? If so, was the \"one\" solution inefficient
as you couldn\'t gain any design economies by scaling up?? Or, if you\'re
tasked with debouncing a membrane keypad? Or, told to delay the switch
action until after a specific period?)

There are countless ways to debounce switches. Thinking that you can pick
one and be anywhere close to \"ideal\" is delusional.

(Hey, why not use mercury wetted contacts on all of your switches -- for
all eternity -- and not sweat the bounce?)

 

[Pimpom]

On 8/13/2020 3:54 PM, Don Y wrote:

On 8/13/2020 2:43 AM, Pimpom wrote:
On 8/13/2020 12:18 PM, Don Y wrote:
On 8/12/2020 11:22 PM, Pimpom wrote:
On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock standalone solution
for future applications.

So, you\'re going to FIX the cost and capabilities of that \"solution\"
without concern for the needs of those \"future applications\"???

shakes head

I don\'t understand the head shaking. Anyone who designs circuits regularly will
have their favourite solution for a common task. I\'ve used various debouncing
techniques but they all require passive components, a particular type of
switch, and in some cases another active device to complement the main active
devices.

If there\'s an inexpensive standalone part that needs no external parts and can
replace those techniques in most applications, what\'s wrong with using that as
a stock solution? A 2N3904/BC547 transistor can be used at the heart of a wide
range of low frequency low power applications. Why hunt for a suitable type
every time?

What do you do when you need a greater Icc? Do you have your \"favorite FET\"?
\"Diode\"? \"Switch\"?

Do you use them regardless of what the *particular* requirements and
constraints of the design happen to be?

You should be reusing ideas, not implementations. So, for example, a
particular amplifier topology -- not a particular set of components to
implement that particular amplifier instance.

You develop a preference for a particular component when you find yourself
using it in many SIMILAR applications. But, that doesn\'t stop you from
reevaluating whether it is APPROPRIATE for a specific NEW application!
You risk limiting your solutions to embrace past experiences instead of
current needs.

(What do you do when you have to debounce 200 pushbuttons -- like on a
video switcher? Do you use the same components -- and techniques! -- that
you did when debouncing ONE? If so, was the \"one\" solution inefficient
as you couldn\'t gain any design economies by scaling up?? Or, if you\'re
tasked with debouncing a membrane keypad? Or, told to delay the switch
action until after a specific period?)

There are countless ways to debounce switches. Thinking that you can pick
one and be anywhere close to \"ideal\" is delusional.

(Hey, why not use mercury wetted contacts on all of your switches -- for
all eternity -- and not sweat the bounce?)

I don\'t know if you\'re deliberately twisting my words or you
really don\'t understand. Having a favourite solution for a class
of applications does not mean that it will invariably be used in
*all* designs. But it\'s good to be able to cover a wide range of
applications with an inexpensive easy-to-use part - a jellybean.
Is that so hard to understand?

There\'s one particular size and pitch of screws that I use a lot.
It doesn\'t mean that I never use screws of another size - or a
different type of fastener - when they\'re called for.

 

[Ricketty C]

On Thursday, August 13, 2020 at 4:01:47 AM UTC-4, Mike Coon wrote:

In article <f4777b32-bd27-4de9-a193-33e548fb3b9do@googlegroups.com>,
gnuarm.deletethisbit@gmail.com says...

Heck, the switches themselves are best replaced with something else.
Switches suck!

I bet you prefer on-(touch)-screen keyboards for typing...

Mike.

I\'m typing on a keyboard with two broken keys. I have a new keyboard but taking a laptop apart is not always so simple.

Laptops suck!

--

Rick C.

+ Get 1,000 miles of free Supercharging
+ Tesla referral code - https://ts.la/richard11209

 

[Klaus Kragelund]

Why would you need debouncing anyway?

Feeding to a flip flop?

If feeding to a micro, then use sw solution

Anyway, a flip flop is more or less the same price as a cheap micro (western micros can be had for around 10 cent in volume)

 

[server]

On Thu, 13 Aug 2020 11:52:18 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 9:13 PM, jlarkin@highlandsniptechnology.com wrote:
On Wed, 12 Aug 2020 15:54:16 +0530, Pimpom <nobody@nowhere.com> wrote:

On 8/12/2020 2:53 PM, TTman wrote:
On 12/08/2020 09:56, Pimpom wrote:
The MAX681* series of switch debouncers look useful but they\'re quite
pricey at >$1 for the single MAX6816 and several $$ for the octal 6818.
Are there any cheaper, easily available alternatives?

For those who are not familiar with the series, these are externally
simple devices that have pins for each mechanical switch and for the
debounced output. Nothing else apart from Vcc and ground. The 40ms
debouncing is done internally without any external component.

I used a maxim reset chip.... if you can live with the 140mS odd delay..
No doubt Microchip do something similar....

Examples?

The MAX809 series has all sorts of uses. The best part is that you
don\'t have to buy them from Maxim.

But as a debouncer, you\'d need more parts.

Exactly, and that\'s what I want to avoid. Otherwise there are a
number of ways to debounce using general-purpose parts.

Some other POR chips might not.

A Schmitt gate would need an RC per switch, which could be in quad
packs.

I\'ve used that and other techniques before.

Why do you need to debounce?

Nothing specific at the moment. I just want to have a stock
standalone solution for future applications.

Going into a uP port pin, sometimes people write elaborate debounce
code. Usually, all you need to to is sample the level 10 times a
second and accept what\'s there.



--

John Larkin Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

 

[Jan Panteltje]

On a sunny day (Thu, 13 Aug 2020 04:37:21 -0700 (PDT)) it happened Ricketty C
<gnuarm.deletethisbit@gmail.com> wrote in
<91a0d592-c204-46c0-8c7f-8a18350d382do@googlegroups.com>:

I\'m typing on a keyboard with two broken keys. I have a new keyboard but taking a laptop apart is not always so simple.

Laptops suck!

Laptops are great,
for one thing those have a build in battery backup for if the mains fails.