Iv'e been working on an A3987 Stepper Motor Controller Breakout board (50v, 1.5A) and working on PCB prototyping techniques. I designed this board to allow me to test all the settings and capabilities of this board, and test a method for setting it into what I call Half Sleep mode. This is all working fine, and I like the A3987 alot.
BTW: to enable half sleep mode I switch a resistor into the voltage divider that feeds the reference voltage to the chip using a small solid state relay. When the voltage drops, the A3987 drops the current in half so the motors will stay cool, but still keep their positions.
Having made many test boards and ironed out the wrinkles: I have written an article on paulwanamaker.wordpress.com - Making Perfect PCBs with the Toner Transfer Method.
Last edited by Paul_W1; 03-13-2012 at 04:05 PM.
That article's address is paulwanamaker.wordpress.com (It originally didn't let me add the link to the first post)
Last edited by Paul_W1; 03-13-2012 at 04:06 PM.