SC1402

© 2000 SEMTECH CORP.

652 MITCHELL ROAD

NEWBURY PARK CA 91320

Multi-Output, Low-Noise Power Supply

Controller for Notebook Computers

December 15, 2000

2

ABSOLUTE MAXIMUM RATINGS

PARAMETERS

MAXIMUM

UNITS

V+, BST3, BST5 to GND

-0.3, +36

V

PGND to GND

± 0.3

V

PHASE3 to BST3, and PHASE5 to BST5

-6 to +0.3

V

VL to GND

-0.3 to 6

V

REF,SYNC,SEQ,PSAVE,TIME_ON5,RESET to GND

-0.3 to (VL+.3V)

V

RUN/ON3, SHDN to GND

-0.3 to (V+ + 0.3V)

V

VDD to GND

-0.3 to +30V

V

12 Out to GND

-0.3 to (VDD + 0.3V)

V

VL, REF Short to GND

Continuous

sec.

12 Out Short to GND

Continuous

sec.

REF Current

+5

mA

VL Current

+50

mA

12 Out Current

+200

mA

VDD Shunt Current

+15

mA

T

-65 to +150

°C

T

+300, 10 seconds

°C

ELECTRICAL CHARACTERISTICS

(1)

(Unless otherwise noted: V+ = 15V, both PWMs on, SYNC = VL, VL load = 0mA, REF load = 0mA, PSAVE = 0V, T

Typical values are at T

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

MAIN SMPS CONTROLLERS

Input Voltage Range

6.0

30.0

V

3V Output Voltage in

Adjustable Mode

V+ = 6V to 30V, CSH3-CSL3 = 0V,

CSL3 tied to FB3

2.45

2.5

2.55

V

3V Output Voltage in Fixed Mode V+ = 6V to 30V, 0mV < CSH3-CSL3 < 80mV,

FB3 = 0V

3.17

3.3

3.43

V

5V Output Voltage in Adjustable

Mode

V+ = 6V to 30V, CSH5-CSL5 = 0V,

CSL5 tied to FB5

2.45

2.5

2.55

V

5V Output Voltage in Fixed Mode V+ = 6V to 30V, 0mV < CSH5-CSL5 < 80mV,

FB5 = 0V

4.82

5.0

5.18

V

Output Voltage Adjust Range

Either SMPS

REF

5.5

V

Adjustable-Mode Threshold

Voltage

Dual Mode comparator

0.5

1.3

V

Load Regulation

Either SMPS, 0V < CSH_-CSL_ < 80mV

-0.8

%

Line Regulation

Either SMPS, 6V < V+ < 30V

0.03

%/V

Current-Limit Threshold

CSH3-CSL3 or CSH5-CSL5

PSAVE = VL or V12OUT < 11.9V

80

-50

100

-100

120

-150

mV

PSAVE Mode Threshold

PSAVE = 0V, not tested

10

25

40

mV

Soft-Start Ramp Time

From enable to 95% full current limit with

respect to f

512

clks

Oscillator Frequency

SYNC = VL

SYNC = 0V

270

170

300

200

330

235

kHz

Maximum Duty Factor

SYNC = VL

SYNC = 0V

94

96

%