Ghani Lawal- Nominal value for pin 7 (Ref) is ~1.2V relative to pin 8 (Adj)
- The LM3915 model in LTSpice significantly breaks down when the current from pin 7 is greater than 2mA
- In the region of interest, current from pin 7 =[0:2mA] resulting in an LED current of [0:20mA], pin 8 can be shorted to ground to enable desired operation
- Iref = 1.1928/Resistance
- Final Design:
- LED's are rated for 20 mA, will cap the max current at 17-18mA
- Pin 7 of each LM3915 IC will be connected to a 680 ohm resistor rated at 0.5W, all of the resistors will be connected to an audio (logarithmic) 10k potentiometer.
Controlling Current Through LED's
A project log for Music Spectrum and dB Visualizer
Receive input from a 3.5mm jack, divides the music into 7 frequency bands, shows the loudness of each frequency band in DB using LEDS.
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