LCD Display Us very dim

Other Hardware Displays
1

My new LCD (16 x2) display is very dim. I have checked my circuit and code. All seems ok. The original LCD that came with an Elego LCD displayed got fried (due to my wiring error). Two new units I purchased off of the internet, didn't work (no illumination at all) right off the bat. Elego sent this new one and I can hardly ready it? I even replaced the rheostat with a 10K resistor, still dim. Ideas?

2

Hello

Post some good picture to see more details.

3

Not sure what you did.

A 10 potentiometer between GND and VO is needed so you can adjust for best visibility.

EDIT
i.e. 10k

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I:\DCIM\100NCD40\DSC_0326.JPG
Picture doesn't show characters, but it is displaying temperature and humidity

5

10 ohm or 10K?

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Paste the image to your post.

10k potentiometer.

7

Post an annotated schematic as to how you have it wired, be sure to include all power, ground, and power supply connections. Links to technical information on the hardware parts will help a lot.

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Here is my schematic>
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DSC_0330
DSC_03301920×2888 196 KB

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Here is my schematic

DSC_0330.JPG
DSC_0330.JPG2000×3008 652 KB

10

Please confirm LCD V0 is connected to the potentiometer wiper.

Terminal A on the potentiometer does not need to be connected to 5v.

Does the LCD back-light come on ?

Let’s see a good image of the actual wiring.

11

Why not @LarryD ? I thought this was pretty normal for the voltage divider circuit to work to generate the contrast voltage?

image
image1280×796 63.9 KB

12

You can connect it to 5v, however, it’s not needed.

13

I learned something new today. :slight_smile:

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Back light is on. V0 is connected to wiper. I'll try to disconnect the one end of the rheostat from +5v, but I can see that it is not needed.

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Here is another thread that is similar to the OP.

My suggestion:

Connect pin 3 of the LCD to ground through a resistor 1K to 330 or install a potentiometer to adjust contrast. Or you can, for testing, connect pin 3 of the LCD directly to ground.

image

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How is this powered?Very nice hand drawn schematic:-)

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Powered from PC

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How do I close this posting

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What do you mean by close? You've flagged a message as being the 'solution'. That's good. In six months or so, with no activity, the topic is automatically closed. Says that right at the bottom of the topic.

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Larry D. was right>When I removed the wire from potentiometer to +5V , the display worked just fine.

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