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20.May.
TSZ22111・15・001
BD6964FVM
3) Problem of GND Line PWM Switching
Do not perform PWM switching of GND line because the potential of GND terminal cannot be kept at the minimum.
Figure 21. GND Line PWM Switching Prohibited
4) AL Output
AL output is an open drain and requires pull-up resistor.
The IC can be protected by adding resistor R1. An excess of absolute maximum rating, when AL output terminal is
directly connected to power supply, could damage the IC.
Fig.22 Protection of AL terminal
Thermal derating curve
Thermal derating curve indicates power that can be consumed by IC with reference to ambient temperature. Power that
can be consumed by IC begins to attenuate at certain ambient temperature. This gradient is determined by thermal
resistance θja.
Thermal resistance θja depends on chip size, power consumption, package ambient temperature, packaging condition,
wind velocity, etc., even when the same package is used. Thermal derating curve indicates a reference value measured
at a specified condition. Figure 23 shows a thermal derating curve.
* Reduce by 4.68 mW/°C over 25°C.
(70.0mm x 70.0mm x 1.6mm glass epoxy board)
Figure 23. Thermal Derating Curve
AL
Protection
Resistor R1
Pull-up
resistor
VCC
Connector
of board
PWM input
Prohibited
VCC
Motor
Driver
GND
Controller
M
Pd(W)
0.7
0.6
0.58
0.5
0.4
0.3
0.2
0.1
0 25
Ta(°C)
