View Full Version : headphone jack digital out load capacity

2005-12-02, 13:28
from the thread on "options for remote power-on", Dean says:

I'm not Sean, but I do have answer from him.

The IR blaster dongles are just infrared LEDs at the end of a long
cable and are available from a number of sources, including us:


The output is from a CMOS driver going through CMOS switch and so it
has a bit of inherent resistance and is current limited and will
drive the LED directly, but will also work as a logic level output.

I would like to drive a solid state relay from the logic level out (it's essentially the same as an IR LED, except using less power but continuously while signalling "power on"). I don't know the specs on the CMOS driver, (or what other loads it has) so I'm not sure if it would be considered an unreasonable load (I need about 8ma at > 1.2V). It would not normally be considered excess, but... If possible, could someone with the appropriate knowledge indicate if it's reasonable to source 8 to 10ma from the output continuously?

Also, I'm presuming that the load would be between the tip (L channel) and ring (R channel), rather than between L or R and ground. Would that be correct?