M54640P
Application Example
Stepper motor
1Ω
820pF
1kΩ
16 15 14 13 12 11 10 9
M54640P
1 2 3 45 67 8
820pF
56kΩ
1Ω
1kΩ
820pF
16 15 14 13 12 11 10 9
M54640P
1 234 567 8
820pF
56kΩ
5V
Phase A
I0A
I1A
24V
47µF
Phase B
I0B
I1B
Precautions for use
(1) When the whole output current changes by a large margin (for example, when overheat protection operation causes
intermittent flow of output current), the supply voltage may undergo a change. Therefore, selection and wiring of power
supply should be conducted cautiously to avoid such a situation that the supply voltage exceeds the absolute maximum
ratings.
(2) When the supply voltage changes by a large margin, the operation of this IC may become unstable. In this case, the
change of supply voltage can be controlled by connecting a capacitor at the point near to IC pin between Vcc pin and
GND pin. (See above application example.)
(3) Thermal shutdown function
• The state of thermal shutdown operation may differ according to the way of wiring within a board. Therefore,
sufficient board evaluation should be conducted before use. When the board is changed, operation on the replacing
board should be evaluated.
• The circuit board on which this IC is mounted is designed to realize low impedance between power supply and
output pin.
Therefore, it is desirable to take a safe measure such as fixing a fuse to avoid such a situation that the board is
damaged by a fire when output pin is internally short-circuited by excessively applied surge voltage by accident.
Rev.1.0, Sep.19.2003, page 8 of 9