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Unread 28-01-2016, 18:23
s1900ahon s1900ahon is offline
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Re: Dynamic Brake/Coast Modes?

Quote:
Originally Posted by GeeTwo View Post
Assuming the outputs of the isolator can handle the current that passes through the jumpers, this should only need a ballast resistor for the LEDs to be enough.
Virtually no current passes through the brake/coast jumper.

On the Jaguar (I cann't speak for the design of others, but I can for Jag) the current involved is that in charging the MCU's GPIO input. The GPIO input uses an internal (to the MCU) pull up which is on the order of 50 kohms. The isolator would only have to pull the input below VIL.

Note that this opto isolator, like the one on Jaguar's PWM input, is inverting.