I was using Arduino for logic and Vcc should have been around or under 5v.
No, did not disconnect the motors. The chip blew up when I put a load on the motors (they were rated at more than 750ma) and probably drew higher current since it happened within 1 second on putting a load on the motors. otherwise, they were operating fine.
I was just surprised that this happens since the datasheet states: "The current in each of the two output H-bridges is regulated with fixed off time pulsewidth modulated (PWM) control circuitry. The H-bridge current at each step is set by the value of an external current sense resistor (RS), a reference voltage (VREF), and the DAC’s output voltage controlled by the output of the translator." and "Adjustable current control from 150mA/phase to 750mA/phase"
So, it should not have let more than 750mA through but it burned when the current demand increased.