LB11852FV

No.A1112-7/12

Description of Pre-driver Bock

*1 : Power-GND wiring

The SGND is connected to the control circuit power supply system.

*2 : Power stabilization capacitor

For the power stabilization capacitor on the signal side, use a capacitor of 0.1

μF or more. Connect the capacitor

between VCC and GND with a thick and along the shortest possible route.

*3 : Power-side power stabilization capacitor

For the power-side power stabilization capacitor, use a capacitor of 1

μF or more. Connect the capacitor between the

power-side power supply and GND with a thick and along the shortest possible route.

*4 : IN+, IN- pins

Hall signal input pins

Wiring should be short to prevent noise from being carried.

If noise is carried, insert a capacitor between the IN+ and IN- pins.

The Hall input circuit functions as a comparator with hysteresis (15mV).

It also has a soft switch zone with

±30mV (input signal difference voltage).

It is also recommended that the Hall input level should be a minimum of 100mV (p-p).

*5 : CPWM pin

Pin to connect the capacitor used to generate the PWM basic frequency

Use of CP = 200pF causes oscillation at f = 30kHz, which is the basic frequency of PWM.

As this is also used for the current limiter reset signal, a capacitor must be connected even if the speed is not going to

be controlled.

*6 : CT pin

Pin to connect the capacitor used for lock detection

The constant-current charging and constant-current discharging circuits incorporated cause locking when the pin

voltage reaches 3.0V, and releasing the lock protection when it drops to 1.0V.

Connect this pin to the GND when it is not to be used (locking not necessary).

*7 : SENSE pin

Current limiter detection pin

When the pin voltage exceeds 0.21V, the current limiter is activated, and operation enters lower regeneration mode.

Connect this pin to the GND when it is not to be used.

*8 : FG pin

Rotational speed detection pin

This is an open collector output that can detect the rotational speed using the FG output corresponding to the phase

changeover.

Keep this pin open when it is not to be used.