Hi guys

What's is the minimum pins I need to drive 4 bi-color leds? I have some d-latchs, inverters. But I don't have shift register. The bi-color leds are common ground/cathode.

Thanks guys!

NOTE: the least I can come up with is 6 pins, in a multiplexing arrangement.

 

Hi guys

What's is the minimum pins I need to drive 4 bi-color leds? I have some d-latchs, inverters. But I don't have shift register. The bi-color leds are common ground/cathode.

Thanks guys!

NOTE: the least I can come up with is 6 pins, in a multiplexing arrangement.

No transistors?

 

Each LED can be turned on individually so you can have red, green, yellow or off.

Hi guys

What's is the minimum pins I need to drive 4 bi-color leds? I have some d-latchs, inverters. But I don't have shift register. The bi-color leds are common ground/cathode.

Thanks guys!

NOTE: the least I can come up with is 6 pins, in a multiplexing arrangement.

 

You have latches? You can have red or green but not yellow or off.
Use the current limiting of the high side driver as the LEDs resistor.

No transistors?

 

Hi guys

What's is the minimum pins I need to drive 4 bi-color leds? I have some d-latchs, inverters. But I don't have shift register. The bi-color leds are common ground/cathode.

Thanks guys!

NOTE: the least I can come up with is 6 pins, in a multiplexing arrangement.

All the same color? Red, green, yellow or off.

 

Thank you all!!

And yes, I can use transistors diode and something like that.

 

depending on the led used but 3 pins (two drive pins and 1 ground/rail) will produce (theoretically) unlimited colors.

 

depending on the led used but 3 pins (two drive pins and 1 ground/rail) will produce (theoretically) unlimited colors.

What kind of LEDs do you have? 3-pin with a common cathode can only get two LEDs. The "any color" LEDs I have seen have 3 LEDs and 4 leads. Do you want "off" to be an option?

 

What kind of LEDs do you have? 3-pin with a common cathode can only get two LEDs. The "any color" LEDs I have seen have 3 LEDs and 4 leads. Do you want "off" to be an option?

I will need 3 states:
Green
Red
Off

 

I will need 3 states:
Green
Red
Off

Individually controlled? I suggest the 74259 version unless you need high brightness. There is a CMOS version of the chip but I don't think the high side driver would drive them.