Ifthe low side emitter is not connected to the motor power return, at least not according to the data sheet. Pin #8 is shown as a "ground" while the motor current is shown using pins #1 and #15. Further on, in the applications segment, the connections are confusing.

Pins 1 and 15 allow the insertion of a current sense resistor between the bridge negative and ground. If the TS is running it without pins 1,4 and 15 connected, I'm not sure how it can be working - the current must be finding a way through the substrate diode

 

https://www.avaq.com/technology/l29...qERm8SEFnCaNt2jY0uJ4gx-4TlZGIVF9zkFpa5fV9fnle

There are so many errors and mis-mashes in different areas of that article that it's not worth using. Go straight to the ST Microelectronics datasheet if using the bare I.C.