Ultra-High Efficiency, Dual Step-Down

Controller for Notebook Computers

2

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ABSOLUTE MAXIMUM RATINGS

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional

operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

V+ to AGND..............................................................-0.3 to +30V

PGOOD, OUT_ to AGND..........................................-0.3V to +6V

ILIM_, FB_, REF, SKIP, TON,

BST_ to AGND........................................................-0.3V to +36V

DH1 to LX1 ...............................................-0.3V to (BST1 + 0.3V)

DH2 to LX2 ...............................................-0.3V to (BST2 + 0.3V)

LX1 to BST1..............................................................-6V to +0.3V

LX2 to BST2..............................................................-6V to +0.3V

REF Short Circuit to AGND.........................................Continuous

28-Pin QSOP (derate 8.0mW/°C above +70°C).....640mW/°C

Operating Temperature Range ..........................-40°C to +85°C

Junction Temperature ......................................................+150°C

Storage Temperature Range ............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

ELECTRICAL CHARACTERISTICS

noted.) (Note 1)

%

0.4

FB2 = GND

Battery voltage, V+

Input Voltage Range

V+ = 24V, OUT2 = 2V

Load Regulation Error

V+ = 24V, OUT1 = 2V

Adjustable mode, each output

Output 2 Error Comparator

Threshold (DC Output Voltage

Accuracy) (Note 2)

TON = GND

FB_ Input Bias Current

TON = GND

TON = open

210

247

280

CONDITIONS

V

TON = REF

142

173

205

ms

OUT_ Input Resistance

µA

Soft-Start Ramp Time

Ω

FB_ = AGND

Rising edge of ON_ to full current limit

2.475

2.5

2.525

V+ = 2V to 28V,

V+ = 2V to 28V,

ns

154

182

215

V

On-Time (PWM2)

ns

112

136

160

0.99

1.00

1.01

On-Time (PWM1)

V

1.7

0.99

1.00

1.01

300

353

407

1.782

1.8

1.818

-0.1

0.1

TON = open

292

336

380

TON = REF

75k

3.267

3.3

3.333

FB1 = AGND

FB1 = OUT1

228

FB2 = OUT2

V

1

5.5

Output Voltage Range

%

0.2

198

234

270

Line Regulation Error

420

484

550

UNITS

MIN

TYP

MAX

PARAMETER

Output 1 Error Comparator

Threshold (DC Output Voltage

Accuracy) (Note 2)

4.5

5.5

Output 1 Error Comparator

Threshold (DC Output Voltage

Accuracy) (Note 2)

V+ = 2V to 28V,

V

0.985

1.00

1.105

1.773

1.8

1.827

3.250

3.3

3.350

FB1 = AGND

FB1 = OUT1

FB2 = GND

Output 2 Error Comparator

Threshold (DC Output Voltage

Accuracy) (Note 2)

2.463

2.5

2.538

V+ = 2V to 28V,

V

0.985

1.00

1.105

FB2 = OUT2