527

Motor driver ICs

BA6840BFS / BA6840BFP-Y / BA6840BFP / BA6842BFS

FCircuit operation

(1)

Hall input

Xoutput

The 3-phase Hall signal is amplified in the hall amplifiers

and sent to the matrix section, where the signal is further

amplified and combined. After the signal is converted to

a current in the amplitude control circuit, the current is

supplied to the output driver, which then provides a motor

drive current. The phases of the Hall input signal, output

voltage, and output current are shown in Fig. 5.

(2)

Torque control pin

voltage (EC) as shown in Fig. 6.

(3)

Start / stop pin

The motor is in the run mode when the pin input voltage

is 3.5V or more, and in the idle mode (all output transis-

tors are off) when the voltage is 1.5V or less.

(4)

sistor (0.5

Ω recommended) between this pin and the

ground to monitor the output current.

(5)

Connect and adjust a capacitor between this pin and the

ground if the output tends to oscillate.