Dear Please help me, I have a problem with your chips L297 and L 298
I made a mini stepper driver for CNC 3-axis and the one we could not work, working chips that are produced around 2006 and are doing well and that this does not work I bought 3 weeks ago.
When you connect electronics to the output between the D (pinout 2) and for all other outputs (pinout 3, 13 and 14) has a voltage of 9.3V, 1.4V and 0.250 V, as soon as I connect the engine and if there is no signal on the control action between 2 and pinout 3 (1 coil motor) is now live and if you are not supposed to be.
I changed the chips for 5 and 7 L297 L298 chips, but the same thing happens all the time, I ask you for help, the scheme can send you if you are interested in is connected.
Theat is my mail , I send theat mail to ST , please if someone know what is problem , I need help.