Cheapest Way to Read Temperature
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I am looking for a cheap way to read temperature of a room. The
DS1822 in on and engineering hold and they have no sub. I was
looking for something like it that doesn't cost a lot.
Troy
DS1822 in on and engineering hold and they have no sub. I was
looking for something like it that doesn't cost a lot.
Troy
Comments
wrote:
> I am looking for a cheap way to read temperature of a room. The
> DS1822 in on and engineering hold and they have no sub. I was
> looking for something like it that doesn't cost a lot.
>
> Troy
Hi Trouy,
a simple PN junction with an op-amp will offer a response with
temperature.
More parts, but should be stuff you have laying around.
a couple pots, a diode for temperature measurement and an op-amp.
Of course it needs calibration, but the cost is quite possibly less
than a quarter.
How cheap were you looking ?
Dave
stand-by DS1620 (3-Wire) or its I2C cousin the DS1621.
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: Troy Bakken [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=PVwGahBRvaH8_h_q2w1f5KRrHXaN6cDJQ7ABPC_vAtZfWJQBnaIoIDyjKPbZbYjTsxZABtH4Jkt9DDU]troybakken@y...[/url
Sent: Thursday, April 22, 2004 6:03 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Cheapest Way to Read Temperature
I am looking for a cheap way to read temperature of a room. The
DS1822 in on and engineering hold and they have no sub. I was
looking for something like it that doesn't cost a lot.
Troy
Just hooked up yesterday and it works alright.
I'm not satisfied with how it's changing temp but I'm now thinking that as
I'm programming and monitoring the debug statements....I realize it was
sitting beside my fan exhaust port on the laptop!! haha
I knew it didn't feel like 80 in the office!
LM35's are another one....but it gives an analog voltage out so you'll need
an A/D or some RCtime work!
sb
Original Message
From: "Troy Bakken" <troybakken@y...>
To: <basicstamps@yahoogroups.com>
Sent: Thursday, April 22, 2004 7:03 PM
Subject: [noparse][[/noparse]basicstamps] Cheapest Way to Read Temperature
> I am looking for a cheap way to read temperature of a room. The
> DS1822 in on and engineering hold and they have no sub. I was
> looking for something like it that doesn't cost a lot.
>
> Troy
>
>
>
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With this thermistor, and a capacitor, use the rc time constant command to
return a pulse time. Put the thermistor in water with ice floating in it
for 32 F. Put the thermistor in water with steam coming off of it (close
enough to boiling) for 220F. Read the RC time constant value for both. Use
a scale factor (with offset) to have the stamp tell you the degrees in F
from those two known values.
The thermistors are within 1% of each other, so you can use the same scaling
for all measurements (assuming your capacitors are of similar quality).
This should get you close enough.
Only 2 parts for each measurement pin.
Original Message
From: Dave Mucha [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=RxZ0DASl3T_LmpY8xkL1YxxCnwRQnv0Wcj8BHUID_0dOr0sICFLYn2VG4ppBO1Os5dxx7dAYFfiCDp_b]davemucha@j...[/url
Sent: Thursday, April 22, 2004 7:14 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Re: Cheapest Way to Read Temperature
--- In basicstamps@yahoogroups.com, "Troy Bakken" <troybakken@y...>
wrote:
> I am looking for a cheap way to read temperature of a room. The
> DS1822 in on and engineering hold and they have no sub. I was
> looking for something like it that doesn't cost a lot.
>
> Troy
Hi Trouy,
a simple PN junction with an op-amp will offer a response with
temperature.
More parts, but should be stuff you have laying around.
a couple pots, a diode for temperature measurement and an op-amp.
Of course it needs calibration, but the cost is quite possibly less
than a quarter.
How cheap were you looking ?
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
while and think they are just perfect. Costly yes, unless you may
get a few from Dallas for free.
Lars
--- In basicstamps@yahoogroups.com, "Jon Williams" <jwilliams@p...>
wrote:
> 1-Wire parts are a pain in the backside anyway ... I'd suggest the
old
> stand-by DS1620 (3-Wire) or its I2C cousin the DS1621.
>
> -- Jon Williams
> -- Applications Engineer, Parallax
> -- Dallas Office
>
>
>
Original Message
> From: Troy Bakken [noparse][[/noparse]mailto:troybakken@y...]
> Sent: Thursday, April 22, 2004 6:03 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Cheapest Way to Read Temperature
>
>
> I am looking for a cheap way to read temperature of a room. The
> DS1822 in on and engineering hold and they have no sub. I was
> looking for something like it that doesn't cost a lot.
>
> Troy