Cytron Technical Forum

Hi....i try to used the 40X2 LCD with SK40C...but the backlight not working because the polarity of the backlight din fit with SK40C (VDD & B/L). So i tried change it with cable connection.........it works but the regulator at SK40C became HOT. What's the problem???? tHANKS.....

nik_kktm WROTE:Hi....i try to used the 40X2 LCD with SK40C...but the backlight not working because the polarity of the backlight din fit with SK40C (VDD & B/L). So i tried change it with cable connection.........it works but the regulator at SK40C became HOT. What's the problem???? tHANKS.....

Change R8 10ohm to a higher value to reduce current to the backlite should slove the problem. I'll try 50 ohm as a start.

Allen

hi...Thanks for reply......it R8 at back of the LCD right? or at SK40C??

Oops, it is right under the 40 pin ic socket on the RHS. And worst is it is a SMD resistor. One way you can do is put another resistor in series with it on JP8 (LCD B/L). Just remove the jumper and solder another resistor of 33 ohm across it.

Look at P5 and P45 of the SK-40C user manual.SK40C

Allen

Haaa thanks a lot Allen.... already done thanks for helping.