ABSOLUTE MAXIMUM RATINGS

Symbol

Parameter

Value

Unit

selflimit

V

Output Peak Pulse Current

1.5

A

Analog Inputs & Outputs (6,7)

-0.3 to 8

V

Analog Inputs & Outputs (1,2,3,4,5,15,14, 13, 16)

-0.3 to 6

V

°C (DIP16)

°C (SO16)

1

0.83

W

W

Junction Temperature, Operating Range

-40 to 150

°C

Storage Temperature, Operating Range

-55 to 150

°C

(*) maximum package power dissipation limits must be observed

THERMAL DATA

Symbol

Parameter

Value

Unit

Thermal Resistance Junction -Ambient (DIP16)

80

°C/W

Thermal Resistance Junction -Ambient (SO16)

120

°C/W

PIN FUNCTIONS

N.

Name

Fun ction

1

SYNC

Synchronization. A synchronization pulse terminates the PWM cycle and discharges Ct

2

RCT

3

DC

Duty Cycle control

4

VREF

5.0V +/-1.5% reference voltage @ 25

°C

5

VFB

Error Amplifier Inverting input

6

COMP

Error Amplifier Output

7

SS

Soft start pin for external capacitor Css

Supply for internal ”Signal” circuitry

Supply for Power section

10

OUT

High current totem pole output

11

PGND

Power ground

12

SGND

Signal ground

13

ISEN

Current sense

14

DIS

Disable. It must never be left floating. TIE to SGND if not used.

15

DC-LIM

Connecting this pin to Vref, DC is limited to 50%. If it is left floating or grounded no limitation is

imposed

16

ST-BY

Standby. Connect a resistor to RCT. Connect to VREF or floating if not used.

SYNC

RCT

DC

VREF

VFB

SS

COMP

1

3

2

4

5

6

7

OUT

SGND

PGND

ISEN

DIS

DC-LIM

ST-BY

16

15

14

13

12

10

11

9

PIN CONNECTION

L5991 - L5991A

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