Does this work?
i added a resistor and a switch to the circuit of the datasheet... LM3915 (page 11, Pin9 internal circuit on page 9)
VCC 12V
V LED PWM 5V
while in dot mode
pin 9 is reverenced to LED9 minus 600mV and if below that threshold LED10 is switched off, this should work since the...
I'm planning on building a VU-Meter/Spectrum Analyzer for a car stereo. The case it is to fit into is a standard DIN chassis(50mm tall & 180mm wide). That's the WINDOW, the actual case is a little bigger. There's room to stack 5 rows high, and 34 LEDs across using 3mm LEDs. Each "row" will be a...
Just started with electronics a few days ago. I decided to build a microphone based VU meter using LM3915 and NE5532 for my first project.
I wired the LM3915 according to the datasheet for a scale between 4.5 V and 7.5V together with some preamp schematic I found on Google.
I really should have...
After searching the internet, I got a lot of clues but no answer. Here is the answer.
The LM3915 bar / dot display driver wants an analog input up to 1.25 volts where the tenth LED comes on.
Arduino analog output is actually PWM at 5 volts, using a 5 volt supply.
This gets a smooth voltage...