488

Motor driver ICs

BA6950FS

FApplication example

FOperation notes

(1)

Thermal shutdown circuit

The thermal shutdown (TSD) circuit turns off all driver

outputs when the IC junction temperature rises above

175

_C (Typ.). The temperature difference between the

activation and deactivation settings is about 20

_C.

STemperature setting of TSD

(2)

Control logic and control signal input pins

Voltage should never be applied to the control logic input

pins (pins 5 and 10) or the control signal input pin (pin 2)

the voltage on each input pin should not exceed any ap-

(3)

PCB arrangement

When changing the rotational direction of a motor, a large

current of up to a few hundred milliamperes can flow be-

tween the motor power supply (pin 6) and RNF (pin 8).

Depending on the application, this large output current

may flow back to input pins, resulting in output oscillation

or other malfunctions. Make sure that your design does

not allow a common impedance between the large cur-

rent output lines and the input section. Suppress the

power supply impedance to low levels, otherwise output

oscillation may occur.

(4)

Package power

The power dissipated by the IC varies widely with the

supply voltage and the output current. Give full consider-

ation to the package power dissipation rating when set-

ting the supply voltage and the output current.

(5)

The input pins (pins 5 and 10) have temperature-

dependent characteristics. Take the temperature effect

into consideration when using the IC.

(6)

To eliminate motor noise, connect a capacitor be-

tween M1 (pin 7) and GND and between M2 (pin 9) and

GND.

Fig.4