Can anyone help me with my digital readout thermometer???

[craigarro]

16f91x a/d

hi, im looking to make a temperature sensor with lcd output display just to display current temp.

i would also like to have a high level alarm with either an l.e.d or piezo sound buzzer.

ive had a search about and from what ive gathered i will be using an lm35 some sort of pic microcontroller and a l.c.d display,

can someone tell me what components i need as far as the micro and do i need an ad converter and amp after my lm35!!!!

just like a little help on this if someone is able, cheers!!!!!

 

[ndru_w]

16f627 thermometer

Hi,
If you'll take a microcontroller with ADC built-in you won't need such sort of thing. LCD with built-in driver (Hitachi's are very popular).

 

[craigarro]

Re: Can anyone help me with my digital readout thermometer??

hmm very interesting so what your saying is i can get away with an lm35/micro with built in adc/l.c.d with driver then all i then need is the c code and other circuit components such as resistors etc!!!

thanx bud i really appreciate the reply!!!!

 

[blueroomelectronics]

Easy with the PIC16F917 with built in LCD controller.
Here's a partial prototype of a future kit thermostat.
I'm currently considering a 4.096V reference (it's a common value for a shunt diode)
**broken link removed**
the display shows the raw A/D value in hex

 

[craigarro]

Re: Can anyone help me with my digital readout thermometer??

Bummer ive just ordered a tlc549 and PIC16F627-04/P to go with an lcd 2x16 display!!! will this work?

 

[blueroomelectronics]

Re: Can anyone help me with my digital readout thermometer??

Bummer ive just ordered a tlc549 and PIC16F627-04/P to go with an lcd 2x16 display!!! will this work?

Sure but you should have picked a PIC with an A/D

 

[craigarro]

Re: Can anyone help me with my digital readout thermometer??

yeah learning curve i suppose!!! ill know for next time!! thanx a lot tho bud much appreciated!!!

 

[blueroomelectronics]

You could use a 16F88 instead of the 16F627

 

[craigarro]

Re: Can anyone help me with my digital readout thermometer??

cool i think ill try that because my A/D converter thats come is too small for my breadboard, i think i should of ordered an in-line?? is that correct?? and my pic hasn't been dipatched yet so ill ring em and tell em to change it for the pic16f88 that you suggested!!! i presume that has an inbuilt A/D converter??

also could you suggest to me an LCD with built in driver or you reckon i should just get a driver ic??? cheers bud.

 

[blueroomelectronics]

The 16F88 has the A/D, nice chip has pretty much everything the 16F877A has but with only 15.5 I/O pins. It has the internal OSC and goes right up to 8MHz. Download the Firefly manual on my site for more info on the 16F88
As for LCD you can hook any standard character LCD with as few as 6 I/O pins. Lots of info on the web, check my links section for a good LCD site.
The built in LCD driver PICs are 16F91x, they come in 28 & 40 pin versions and can directly drive a cheap simple LCD no problem. Takes more pins than a character LCD though.