LCD backlight overheats 7805

[mvs_sarma]

Hi,

Acetronics is right in recommending 22ohms and i saw other designs (IK3OIL's frequency counter using LCD display) indicating backlit LCDs draw 60 mA and recommend 7805 but NOT 78L05. No heatsink is noticed.

Hi DynamoBen,

did you use 12V ,7805 and 11ohm resistor for Backlit? Still find No heat?

[DynamoBen]

I have since moved the backlight to my 12V source. That seems to work fine.

[mvs_sarma]

Hi

And would have increased the resistor value to say 47 ohms nearly.. it is a good idea and now even a 78L05 will do ( ofcourse in and out pins are diffrent.)
GOOD improvisation

[Acetronics2]

Hi

And would have increased the resistor value to say 47 ohms nearly.. it is a good idea and now even a 78L05 will do ( ofcourse in and out pins are diffrent.)
GOOD improvisation

Hi, Sarma

When using 78L05 ... just think to have very good decoupling caps.
the internal impedance of the L series sometimes may cause little surprises with PMW use or with outputs loaded ...

Think to the LM 317 L that has a lower output impedance !!! ... or keep the 7805.

Alain