Too much power for the ULQ2003A

[Russ7284]

Hello, I am building a motor driver circuit and the ULQ2003A works great for me.  That is until I changed the motor out, now my motor is drawing 2 amps rather that 350mA.  My question is, is there a substitute for the ULQ2003A Darlington Transistor Array that can handle 2- 4 amps at 5vdc.  I seemed to have melted the last 2, as well as ruined one of my test boards.  Thanks in advance.

-Russ

 

[ante1]

Hi Russ,

You have to "boost" the outputs of the array with power transistors for this level of current! The ruined board is probably not made for this current and you better build the “boost” circuit on a PCB.

 

[Russ7284]

So should I connect the output of the ULQ2003 to the base and the emitter to ground and the collector to the motor coil?  or is there a better method?  Would I need a pull-up resistor in this case? 

 

[ante1]

Hi Russ,

These circuits does not use the same driver circuit as you do but they might give you some idea.

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