Hello to all from a newbie member.
I have a circuit dilema that I am hoping a thousand minds are better than one.
I have put together an LED driver circuit to show voltage from 0 - 4V using the LM3914 (Please see attached for schematic)
I have made a prototype on breadboard and the thing just does not work corrrectly. I get all the LED's lit up all the time, without ANY I/P on pin 5
Just to make sure I have costructed this correctly can you peeps please confirm my pin outs & cct please
Pin 1 to LED #1
Pin 2 to 0V (V-)
Pin 3 to 8V supply from LM317T (V+)
Pin 4 to 0V (Reference Low)
Pin 5 I/P (Signal)
Pin 6 10K pot divider to give 4V FSD (Reference Hi)
Pin 7 1K2 to 0V for If of LED's (Reference Out)
Pin 8 to 0V (Reference Adjust)
Pin 9 to 8V supply for 'Bar' mode (Mode)
I have redone this circuit at least ten times and it is the same every time.
Please can someone help me as it is driving me mental
Thanks everyone
Transducer
I have a circuit dilema that I am hoping a thousand minds are better than one.
I have put together an LED driver circuit to show voltage from 0 - 4V using the LM3914 (Please see attached for schematic)
I have made a prototype on breadboard and the thing just does not work corrrectly. I get all the LED's lit up all the time, without ANY I/P on pin 5
Just to make sure I have costructed this correctly can you peeps please confirm my pin outs & cct please
Pin 1 to LED #1
Pin 2 to 0V (V-)
Pin 3 to 8V supply from LM317T (V+)
Pin 4 to 0V (Reference Low)
Pin 5 I/P (Signal)
Pin 6 10K pot divider to give 4V FSD (Reference Hi)
Pin 7 1K2 to 0V for If of LED's (Reference Out)
Pin 8 to 0V (Reference Adjust)
Pin 9 to 8V supply for 'Bar' mode (Mode)
I have redone this circuit at least ten times and it is the same every time.
Please can someone help me as it is driving me mental
Thanks everyone
Transducer
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