Needed Assistance - EMI Issues with 16x2 LCD Display (Model BCB-1602-03C)

[Yogesh_D]

Hello Community,

I am Yogesh D from Trident Pneumatics Private Limited, R&D Innovation - Electronics. We are currently using a 16x2 LCD display (model BCB-1602-03C) in the controllers of our dryers. However, we are encountering significant EMI issues that are affecting the display's performance.

The specific issues we are facing include:
- Distortion of characters on the display
- Discoloration and character mismatch

We are using the PIC 16F 876A - E/S P microcontroller in our circuit. I have attached the schematic diagram of our current setup for reference.




We would greatly appreciate any guidance or suggestions from the community on how to resolve these EMI issues.
We would be very thankful if any of you resolve the issue and give the altered schematic diagram.
If anyone has encountered similar problems or has experience with EMI mitigation for LCD displays, your insights would be invaluable.

Thank you in advance for your assistance.

 

[bidrohini]

Use a metal enclosure or a shielded box around the LCD and sensitive parts of the circuit. The shield should be properly grounded.

 

[Yogesh_D]

Use a metal enclosure or a shielded box around the LCD and sensitive parts of the circuit. The shield should be properly grounded.

Thankyou @bidrohini. can you send us the schematic diagram apart from the conductive shielding.
As we are bulk manufactures of Dryers, we need to undergo the certification, so we are more looking for the electronic circuit alteration for EMI filtration

 

[Delta Prime]

As we are bulk manufactures of Dryers, we need to undergo the certification, so we are more looking for the electronic circuit alteration for EMI filtration

Clarification needed! Full disclosure...
I would look for the EMI source.
Could be conductive, internal,EMC it could be radiated external RFI, that would depend on your environment.

we are encountering significant EMI issues that are affecting the display's performance.

I would have to see the PCB layout and wiring diagram.
By the way...

(model BCB-1602-03C)

Talk about the bottom of the barrel geez...
I mean come on....
Stiffen up your DC power bus by adding electrolytic capacitors in the range of 47uF
To 470uF as close as possible to the display and your Micro-P
And it wouldn't hurt if you tried this...

 

[Yogesh_D]

Clarification needed! Full disclosure...
I would look for the EMI source.
Could be conductive, internal,EMC it could be radiated external RFI, that would depend on your environment.

I would have to see the PCB layout and wiring diagram.
By the way...

Talk about the bottom of the barrel geez...
I mean come on....
Stiffen up your DC power bus by adding electrolytic capacitors in the range of 47uF
To 470uF as close as possible to the display and your Micro-P
And it wouldn't hurt if you tried this...


View attachment 63934

Thank you @Delta Prime for your valuable information