LB1991V

No.5792-5/7

Pin Function

Pin No.

Pin name

Pin function

Equivalent circuit

1

VCC1

Supply voltage for all circuits other than the IC internal

output block and the amplitude control block.

2

VCC2

Supply voltage for the IC internal output control block and

the amplitude control block.

3

VS

Motor drive power supply. The voltage applied to this pin

must not exceed VCC2.

5

UOUT

U phase output.

7

VOUT

V phase output.

9

WOUT

W phase output.

(These outputs include built-in spark killer diodes.)

6,8

RF

Ground for the output power transistors.

3

5

6

(8)

2

(7,9)

VCC2

VS

RF

10k

Ω

5k

Ω

5k

Ω

1/2

×VS

1/4

×VS

Each

OUT

10

VH+

11

VH−

Hall element bias voltage supply.

A voltage that is typically 0.95V is generated between the

VH+ and VH− pins (When IH is 5mA).

11

1 VCC1

VH−

10

VH+

20k

Ω

About

1.9V

About

0.9V

13

GND

Ground for circuits other than the output transistor.

The RF pin potential is the lowest output transistor potential.

14

FRC

Forward/reverse selection. Applications can select motor

forward or reverse direction rotation using this pin. (This pin

has hysteresis characteristics.)

15

STBY

Selects the bias supply for all circuits other than the FG

comparators.

The bias supply is cut when this pin is set to the low level.

14

VCC1

FRC

50k

Ω

15

VCC1

STBY

100k

Ω

16

17

UIN1

UIN2

U phase Hall element input.

The logic high level is the state where the IN+ voltage is

greater than the IN− voltage.

18

19

VIN1

VIN2

V phase Hall element input.

The logic high level is the state where the IN+ voltage is

greater than the IN− voltage.

20

21

WIN1

WIN2

W phase Hall element input.

The logic high level is the state where the IN+ voltage is

greater than the IN− voltage.

12

ANGLE

Hall input/output gain control. The gain is controlled by the

resistor connected between this pin and ground.

16

VCC1

4k

Ω

17

400

Ω 400Ω

200

Ω

4k

Ω

200

Ω

(18,20)

(19,21)

0.3V

1

17

VCC1

ANGLE

1.2V typ

Each

input of 1

Each

input of 2

22

FGIN+

FG comparator non-inverting inputs.

There is no internally applied bias.

23

FGIN−

FG comparator inverting inputs.

There is no internally applied bias.

24

FGOUT

FG comparator outputs.

There is an internal 20k

Ω resistor load.

1

VCC1

24

200

Ω

23

200

Ω

22

FGIN−

FGIN+

FGOUTN