I have one of those LCD 0-200mV panel meters that I want to boost its sensitivity to 0-50mV. Absolute accuracy is not important, more of an 'indication'. Any suggestions how to best do this?
JERD
- posted
16 years ago
Boosting LCD panel meter sensitivity
Loading thread data ...
- Vote on answer
- posted
16 years ago
Add a non-inverting gain 4 pre-amplifier, say using a low power single opamp chip. Choice of chip depends on power supply alternatives.
HTH, Glenn.
- Vote on answer
- posted
16 years ago
Hi Glenn and thanks for this info. Power supply is 12v DC. Can you give me a pointer to suitable IC please? I'll have a friend make it up for me
Ta! JERD
- Vote on answer
- posted
16 years ago
"JERD"
** It don't make sense to even try.A 3.5 digit display has 2000 counts so cannot show " 50.00 mV " - it can only show " 050.0 mV " which it will do as it is right now.
....... Phil
- Vote on answer
- posted
16 years ago
The easy way out, near the trimpot there's a resistor R2 ~ 27K -30k that controls the ref voltage to100mv for 200mV FS. Half that resistor by placing another 27K in parralel, to give you 50mv ref adjust the trimpot if needed. the result will be 0 to100mv meter. see ICL7106 data sheet for more info.
Cd954