lcd and lm35 problem

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lcd and lm35 problem

Postby ZaM » Mon Feb 07, 2011 5:42 pm

my new lcd keep blinking but when i change with old lcd it alright...
at 5 second, lm35 it seen overheat when i supply 5v at 1 pin ,not connect at 2 pin and gnd at 3 pin same as in data sheet...any idea?? or it normal for lm35 but not any output at 2 pin when connect to microcontroller..
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Re: lcd and lm35 problem

Postby ABSF » Tue Feb 08, 2011 9:59 am

Did you measure the current consumed by your LM35 when overheating? If it is higher than the max current in datasheet, then it's too high.

There are op-amps inside LM35, so it is likely that the chip is oscillating. Did you try putting a 0.1uF cap across Pin 1 & 3 next to your LM35 and see if it helped ?

Allen
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Re: lcd and lm35 problem

Postby ober » Tue Feb 08, 2011 12:35 pm

LCD keep blinking, blinking referring to the LCD backlight or the message itself? What type of power source you are using? 9V battery or AC to DC adapter? Anyway, if the problem still persist, please fill in the form under support tab at Cytron website, the technical team will follow up with you.

Never tested LM35 in that condition, but pin 2 is output and even if you do not connect anything, it should not cause any extreme heat. Is the pin 1 and pin 3 is correctly connected? Because in the data sheet, the TO-92 package is bottom view, not top view. A lot of user make mistake on that, and connect the +Vs to Gnd and Gnd to 5V.
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Re: lcd and lm35 problem

Postby ZaM » Tue Feb 08, 2011 5:44 pm

ABSF: i use 5v power that i get from sk40c using Adapter Teletron TMC-500PM, i not measure the current yet but thank for help.
ober: lcd message blingking, i refer to data sheet for pin configuration
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Re: lcd and lm35 problem

Postby sich » Wed Feb 09, 2011 7:38 am

ZaM WROTE:lcd message blingking

If it's because of your program, may be the delay you use for your LCD routine is too much than what it needs.
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