High-Speed Step-Down Controller with

Accurate Current Limit for Notebook Computers

4

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ELECTRICAL CHARACTERISTICS (continued)

°C to +85°C, unless otherwise noted. Typical values are at

°C.)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

MAX1844EEP

1.5

5

DH Gate-Driver On-Resistance

(Note 4)

BST - LX forced to 5V

MAX1844EGP, MAX1844ETP

1.5

6

Ω

MAX1844EEP

1.5

5

DL Gate-Driver On-Resistance

(Note 4)

DL, high state

MAX1844EGP, MAX1844ETP

1.5

6

Ω

MAX1844EEP

0.5

1.7

DL Gate-Driver On-Resistance

(Note 4)

DL, low state

MAX1844EGP, MAX1844ETP

0.5

2.7

Ω

DH Gate-Driver Source/Sink

Current

DH forced to 2.5V, BST-LX forced to 5V

1

A

DL Gate-Driver Source Current

DL forced to 2.5V

1

A

DL Gate-Driver Sink Current

DL forced to 5V

3

A

DL rising

35

Dead Time

DH rising

26

ns

Logic Input High Voltage

LATCH, SHDN, SKIP

2.4

V

Logic Input Low Voltage

LATCH, SHDN, SKIP

0.8

V

Logic Input Current

LATCH, SHDN, SKIP

-1

+1

µA

Dual Mode Threshold, Low

OVP, UVP, FB

0.15

0.20

0.25

V

OVP, UVP

Dual Mode Threshold, High

FB

1.9

2.0

2.1

V

V

TON Float Voltage

3.15

3.85

V

TON Reference Level

1.65

2.35

V

TON GND Level

0.5

V

TON Input Current

-3

+3

µA

ILIM Input Leakage Current

-100

0

+100

nA

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Battery voltage, V+

2

28

Input Voltage Range

4.5

5.5

V

FB = OUT

0.985

1.015

FB = GND

2.462

2.538

Error Comparator Threshold

(DC Output Voltage Accuracy)

(Note 1)

V+ = 4.5V to 28V,

1.773

1.827

V

TON = GND

(600kHz)

140

180

TON = REF(450kHz)

175

225

TON = Unconnected

(300kHz)

260

320

On-Time

V+ = 24V,

(Note 2)

380

470

ns

ELECTRICAL CHARACTERISTICS

°C to +85°C, unless otherwise noted.) (Note 3)