LB1845

No.5505-5/9

Pin Description

Pin No

Pin

Function

1, 14

VBB

Output stage power-supply voltage

2

13

SENSE1

SENSE2

Set current detection pins.

Connect these pins, fed back through noise filters, to E1 and E2.

3

12

E1

E2

The set current is controlled by the resistors Re inserted between these pins and ground.

4, 11

D-GND

Internal diode anode connection

6

7

8

9

OUT1B

OUT1A

OUT2B

OUT2A

Outputs

15

GND

Ground

27

16

RC1

RC2

Used to set the output off time for the switched output signal.

The fixed off times are set by the capacitors and resistors connected to these pins. toff = CR.

26

17

VREF1

VREF2

Output current settings

The output current is determined by the voltage (in the range 1.5 to 7.5V) input to these pins.

25

18

PHASE1

PHASE2

Output phase switching inputs.

High-level input: OUTA = high, OUTB = low

Low-level input: OUTA = low, OUTB = high

24

19

ENABLE1

ENABLE2

Output on/off settings

High-level input: output off

Low-level input: output on

22, 23

21, 20

I01, I11

I02, I12

Digital inputs that set the output current

The output currents can be set to 1/3, 2/3, or full by setting these pins to appropriate combinations of high and low levels.

28

VCC

Logic block power supply

Timing chart for pin switching operations during PWM drive

Figure 1 Switching Waveforms

toff: Output off time. Determined by external capacitor and resistor Ct and Rt. (toff ≈ Ct × Rt)

td: Delay time between the point the set current is sensed at the SENSE pin and the point the output turns off.

ILB00884

RC pin

E pin

SENSE pin

VOUT pin

td

Spike noise

toff