Hello All
I am trying to make some stuff on LCD , I have purchase new LCD JND162A and write one simple code and burn it on Atmega32A.
I found this is not working , LCD not showing any thing ,no any box structure only green light turn on. I had check my connection several times.
I had check this on Proteus simulation software, code and LCD works properly.

Connection method I had follow
1) VSS=gnd ,VCC-5v, VEE-5v directly ,LED+ -5v, LED- - gnd directly and data pins respectively .
2)VSS=gnd ,VCC-5v ,VEE- 10k POT ,LED+- 5v through 330OHM ,LED- - gnd directly and data pins respectively.

Is my LCD is damage with this first method of connection ?
Is any proper way to check or test LCD with out connecting to Micro controller ?
Is any way to repair LCD JHD162A ?

 

I have just found one method
https://protostack.com.au/2010/03/character-lcd-displays-part-1/

 

Apply power and adjust contrast setting until you see rectangular boxes.

 

Apply power and adjust contrast setting until you see rectangular boxes.

I have applied both .but directly from 5v and gnd respectively as i mention in method

 

Connect 1kΩ resistor from pin-1 (Vss) to pin-3 (VEE).

 

Vee (pin 3) is your contrast voltage. you need to use a potentiometer (5K, 10K, 20K will work) as a voltage divider (one end to Vss, other end to Vdd and the wiper to Vee). Adjust until you see blocks and then tweak it for the best display.

 

Vee (pin 3) is your contrast voltage. you need to use a potentiopalso ot meter (5K, 10K, 20K will work) as a voltage divider (one end to Vss, other end to Vdd and the wiper to Vee). Adjust until you see blocks and then tweak it for the best display.

I use 4.7k ohm directely and then after that i check with 10k pot also ..but i wont see any blocks.
So is my LCD is damage ?

 

It could be but it could also be any number of issues. Have you verified the voltages Vss - Vdd and Vss - Vee with a DMM? What voltage are you seeing?

 

It could be but it could also be any number of issues. Have you verified the voltages Vss - Vdd and Vss - Vee with a DMM? What voltage are you seeing?

VSS to VCC and VSS to VEE both are at 5 volt .

 

OK, VEE should be somewhere between 0 and 5V - it needs to be adjustable.

 

Try a small diode, 1N914 or 1N4148 for example, anode to VEE and cathode to VSS. In most cases that will work ok in place of a pot. Then the screen should show blocks when it powers up.
But yes, if the VEE is at 5V, it will not work.

 

Try a small diode, 1N914 or 1N4148 for example, anode to VEE and cathode to VSS. In most cases that will work ok in place of a pot. Then the screen should show blocks when it powers up.
But yes, if the VEE is at 5V, it will not work.

thank you dendad i will check this today and make you inform.