Sample Application Circuit Output Waveforms

No. 4943-4/5

LB1863M, 1869M

Truth Table

Design Documentation (See the application circuit diagram.)

Since these miniature flat package products supply power to the Hall amplifier block and the control block from an

internal parallel regulator, they operate with good stability with respect to kickback currents from the motor and

variations in the power-supply voltage. They also provide an adequate ability to withstand surges. The resistor R1

in the fan motor power-supply voltage range.

following formula.

R1

• Abnormal voltage considerations

up to the plus side abnormal voltage Vsurge give by formula (2).

2. Hall input pin voltages (IN– and IN+ pins)

the Hall input pins to the output pin is over 100 dB. The Hall input amplifier offset voltage is ±7 mV. This means that

the Hall element output must be set up taking this ±7 mV offset into account.

3. Output transistors (OUT1 and OUT2 pins)

Applications should adopt one of the following three output protection techniques.

Œ If a capacitor is inserted between OUT and ground, use a capacitor with a value up to C = 10 µF, and design that

 If a Zener diode is added, determine a value for the Zener voltage that is lower than V

noise is a problem, insert a capacitor between B1 and B2.

Ž If a capacitor is inserted between OUT and B1, set the capacitor value so that the kickback voltage is lower than

IN+

IN–

C

OUT1

OUT2

RD

H

L

L

H

L

L

L

H

L

L

H

L

H

L

H

H

H

H

L

H

H

H

H

H