LB1980H

No.5974-6/7

VLIM=5V

CTLREF: OPEN

Gm1=0.58A / V typ

2.10V typ

Control Characteristics

VCTL

0

123

4

5

VCTL=5V

CTLREF: OPEN

Control Limiter Characteristics

VLIM

01

2

3

4

200mA / V typ

Slope: 0.50A / V typ

Continued from preceding page.

Pin No.

Pin Name

Function

Equivalent circuit

11

CTL

Speed control input. The control implemented is fixed

current drive controlled by current feedback from Rf.

Gm=0.58 / V (typical) when Rf=0.5W

12

CTLREF

Control reference voltage. While this pin is set to about

0.43

×VCC internally, this voltage can be modified by

applying a voltage from a low-impedance circuit.

(The input impedance is about 4.3k

Ω).

13

LIM

Current limiter function control. The output current can be

varied linearly by applying a voltage to this pin.

The slope is 0.5A / V (typical) when Rf=0.5

Ω.

CTL

CTLREF

VCC

VCC

VCC

7.5k

Ω

10k

Ω

200

Ω

200

Ω

LIM

200

Ω

100

µA

200

µA

max

11

13

12

15

16

17

18

19

20

UIN+

UIN-

VIN+

VIN-

WIN+

WIN-

U phase Hall element inputs.

Logic high is defined as states where IN+>IN-.

V phase Hall element inputs.

Logic high is defined as states where IN+>IN-.

W phase Hall element inputs.

Logic high is defined as states where IN+>IN-.

200

Ω

100

µA

200

Ω

(+) input

19

17

15

(--) input

20

18

16

21

VCC

Power supply for all internal blocks other than the output

block. This voltage must be stabilized so that noise and

ripple do not enter the IC.

Truth Table and Control Functions

Hall input

Source

→ Sink

U

V

W

FR

Phase V

→ Phase W

H

1

Phase W

→ Phase V

H

H

L

L

Phase U

→ Phase W

H

2

Phase W

→ Phase U

H

L

L

L

Phase U

→ Phase V

H

3

Phase V

→ Phase U

H

L

H

L

Phase W

→ Phase V

H

4

Phase V

→ Phase W

L

L

H

L

Phase W

→ Phase U

H

5

Phase U

→ Phase W

L

H

H

L

Phase V

→ Phase U

H

6

Phase U

→ Phase V

L

H

L

L

Note: Since the drive technique adopted is a 180

° technique, phases other than the sink and source phase do not turn off.

Control Function and Current Limiter Function

Note: In the FR column, “H” refers to a voltage of

2.75V or higher, and “L” refers to 2.25V or

lower (when VCC=5V.)

Note: In the Hall input column, “H” refers to the state

in the corresponding phase where the +input is

at a potential at least 0.01V higher than the

-input, and “L” refers to the state where the

-input is at a potential at least 0.01V higher than

the +input.