biboymusic
Member
I can't seem to make my project work the way I want it to. Im using an LM3914 IC for the LED Bar gauge. Please help me... Here are the points of my project:
1.) My motorcycle is running on 12Volts
2.) The fuel sender have 2 wires and only 1 wire goes to the analog gauge (Resistance: 100 Ohms empty & 8 Ohms full).
3.) The circuit I used was the one on the Datasheet (Page 11). I used variable resistors for adjustments and calibration.
4.) I cannot determine the voltage from the sender because it reads 12v being it as a ground. But testing it disconnected reads the resistance range mentioned in #2.
5.) The senders output has a smooth resistance variation (e.g. Potentiometer type I guess)
Can anyone give me an idea on what resistor combination to use or a schematic that will make the above given values function? Do I need to step down the voltage? Do I need a regulator?
I badly need help on this.
@12v power, the gauge should light full on full tank (8 Ohms) and no lights at empty (100 Ohms).
Thanks and more power.
P.S. I'm good at PIC's (a programmer by nature) but not on this traditional circuit logic.
1.) My motorcycle is running on 12Volts
2.) The fuel sender have 2 wires and only 1 wire goes to the analog gauge (Resistance: 100 Ohms empty & 8 Ohms full).
3.) The circuit I used was the one on the Datasheet (Page 11). I used variable resistors for adjustments and calibration.
4.) I cannot determine the voltage from the sender because it reads 12v being it as a ground. But testing it disconnected reads the resistance range mentioned in #2.
5.) The senders output has a smooth resistance variation (e.g. Potentiometer type I guess)
Can anyone give me an idea on what resistor combination to use or a schematic that will make the above given values function? Do I need to step down the voltage? Do I need a regulator?
I badly need help on this.
@12v power, the gauge should light full on full tank (8 Ohms) and no lights at empty (100 Ohms).
Thanks and more power.
P.S. I'm good at PIC's (a programmer by nature) but not on this traditional circuit logic.
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