One output to many output?

Projects General Guidance
1

Hi everyone,
Is it possible to use one pin output and depending on the analogWrite() intensity, have it decide which led to light up?

Thanks

2

Yes, you can use the LM3914 LED driver
http://www.biltek.tubitak.gov.tr/gelisim/elektronik/dosyalar/21/LM3914.pdf
Using circuit some thing like this

800×532 9.3 KB

and your PWM pin signal pass thru low pass filter to get the DC voltage to drive the LM3914 input.

3

Hello there BillHo,
Are there any that you can get from a local RadioShack? What I'm trying to do is light up some LED but I only have 2 available pins left. Do you have any recommendations if you are running out of pins to light up your LED?

Thanks

4

SeanD:
What I'm trying to do is light up some LED but I only have 2 available pins left. Do you have any recommendations if you are running out of pins to light up your LED?

How many LED? you can try this
http://arduino.cc/en/Tutorial/ShiftOut

5

Sure, use your 2 pins control aregister. Clock & Data.

Here's an example using a similar part. Data is clocked thru, and shows up on the output with each clock (vs a 74HC595, where an extra clock signal latches the output register).

shift_register_74F374.jpg
shift_register_74F374.jpg960×720 51.4 KB

6

Thanks guys! I think I will be ordering a few shift registers. it seems to fit my purpose.