L6219 - dead or alive?

Discussion in 'General Electronics Chat' started by quantt, Dec 29, 2012.

  1. quantt

    Thread Starter New Member

    Dec 29, 2012
    Dear All,

    I'm working on a conversion project for desktop inkjet printer into flat-bed (direct-to-garment) one. My problem is that after some changes printer started going into 'fatal error' state in the middle of the start up routine.

    My best hypothesis is that L6219 chip driving one of the stepper motors is cooked. Controller expects movement, but it doesn't happen, so it throws hands up. The chip is commodity, replacement easily obtainable, but I'd like to make sure it is really dead before I commit into daunting task of reworking the board.

    I'm suspicious about the chip because all four outputs (two per winding, it's a bipolar stepper motor) are shorted together inside the chip. To my best understanding this shouldn't happen as two windings operate in isolation. The other thing is that I can see input from the board microcontroller going into the chip, but can't sense any output.

    Do you guys know how to check if L6219 chip is in good working order? Alternatively, if you have such chip working, could you check if all individual outputs (OUT1A, OUT1B, OUT2A, OUT2B) are not shorted?

    Many thanks!