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icl7106 + LCD (help this amateur girl)


zeeq

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Hello guys.

I am doing digital voltmeter with icl 7106 and with lcd. I have schematic of that voltmeter from icl 7106 pdf (intersil ). So I have two or three questions.
I have lcd ( i think its 3.5 digits), and theres 20 pins above, and 20 below. So, I am looking the schematic now and dont know where to connect pins of icl (2-20, and 21-25) ? I mean, which pin of the lcd should I connect with lets say pin5 ?

second.. If I measure 200V voltage, how will it shows on display : 200 or 200.0 ? I am asking this because I will put voltage divider, so i dont know can it shows voltage on lcd higher than 999 ( because of dot . ) If it is showing 200.5 , and than i want to measure over 1000 (very unlikely i am going to measure that high) , do I have to move dot (.) manually or it will do automaticly (sory if it is silly question) .

Thanks a lot even if you only read this stupid very amateur questions.. ;D

scheme 

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Here are the complete instructions from a kit based on this chip:
http://kitsrus.com/projects/k127.pdf
Your LCD display should have corresponding pins with the same markings. This instruction set is much more complete than the Intersil data sheet, and explains the voltage divider as well.
Hope it helps.

MP

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Thank you for LCD display pins sceme. It helped.
I was doing this scheme in attach. and I know everything how to connect, and I connect well. But it doesnt work  ??? .
I calibrated first. The output is 200mV, and between pins ( i think 35 and 36) must be half of it (100mv) and it is (measured with voltmeter from store).
So I measured battery ( 130mv with voltmeter from store) and voltage is on mine about 340mv (weird).  So I connect voltage divider, paralel on input I put 100 Kohm , and in serial (dont know is this proper english word) 1 Mohm.

That voltage divider its OK, it have to works.
I tried to calibrate, so between pins must be 10V because this is for 20V. But  voltmeter from store shows about 1 V .  ???  When on my voltmeter is this 20V range, the LCD doesnt shows only dot (what it shoud), it shows number 13.5  but nothing is connected on input, no baterry, none voltage.

So I dont know whats going on. And everything is connected perfectly like on this scheme.

I will try tomorow, when I get 820 ohm resistor, to do the scheme that  MP /thank you again/ gave me. 

my scheme:

if you cant see values of resistors and other stuff :

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