Dual-Output Power-Supply

Controller for Notebook Computers

2

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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.

ELECTRICAL CHARACTERISTICS

ABSOLUTE MAXIMUM RATINGS

V+ to GND................................................................-0.3V to 36V

PGND to GND .......................................................................±2V

VL to GND ..................................................................-0.3V to 7V

BST3, BST5 to GND .................................................-0.3V to 36V

LX3 to BST3 ...............................................................-7V to 0.3V

LX5 to BST5 ...............................................................-7V to 0.3V

Inputs/Outputs to GND

(D1, D2, SHDN, ON5, REF, SS5, CS5,

FB5, SYNC, CS3,FB3, SS3, ON3) ............-0.3V to (VL + 0.3V)

VH to GND ...............................................................-0.3V to 20V

Q1, Q2 to GND ............................................-0.3V to (VH + 0.3V)

DL3, DL5 to PGND .......................................-0.3V to (VL + 0.3V)

DH3 to LX3 ..............................................-0.3V to (BST3 + 0.3V)

DH5 to LX5 ..............................................-0.3V to (BST5 + 0.3V)

REF, VL Short to GND................................................Momentary

REF Current ........................................................................20mA

VL Current ..........................................................................50mA

SSOP (derate 9.52mW/°C above +70°C)....................762mW

Operating Temperature Ranges

MAX786CAI/MAX786_CAI .................................0°C to +70°C

MAX786EAI/MAX786_EAI ...............................-40°C to +85°C

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

MAX786S

MAX786R

MAX786

FB3 Output Voltage

3.46

3.65

3.75

V

0mV < (CS3-FB3) < 70mV, 6V < V + < 30V

(includes load and line regulation)

3.32

3.50

3.60

REF Load Regulation

30

75

mV

PARAMETER

VL Output Voltage

MIN

TYP

MAX

4.5

5.5

UNITS

Current-Limit Voltage

V

80

100

120

VL Fault Lockout Voltage

mV

Line Regulation

3.6

4.2

0.03

%/V

Load Regulation

2.5

V

%

3.17

3.35

3.46

VL/FB5 Switchover Voltage

SS3/SS5 Source Current

2.5

4.0

6.5

µA

4.2

4.7

V

REF Output Voltage

SS3/SS5 Fault Sink Current

2

3.24

3.36

mA

V

REF Fault Lockout Voltage

2.4

3.2

V

Input Supply Range

5.5

30

V

FB5 Output Voltage

4.80

5.08

5.20

V

CONDITIONS

CS3-FB3 or CS5-FB5

Falling edge, hysteresis = 1%

Either controller (V+ = 6V to 30V)

Either controller (CS_ -FB_ = 0mV to 70mV)

Rising edge of FB5, hysteresis = 1%

No external load (Note 1)

0mV < (CS5-FB5) < 70mV, 6V < V + < 30V

(includes load and line regulation)

Falling edge

V+ Shutdown Current

25

40

µA

–

S

—

H

—

D

—

N

–

= D1 = D2 = ON3 = ON5 = 0V, V+ = 30V

V+ Standby Current

70

120

µA

D1 = D2 = ON3 = ON5 = 0V, V+ = 30V

Quiescent Power Consumption

(both PWM controllers on)

5.5

8.6

mW

D1 = D2 = 0V, FB5 = CS5 = 5.25V,

FB3 = CS3 = 3.5V

V+ Off Current

30

60

µA

FB5 = CS5 = 5.25V, VL switched over to FB5

D1, D2 Trip Voltage

1.61

1.69

V

Falling edge, hysteresis = 1%

D1, D2 Input Current

±100

nA

D1 = D2 = 0V, 5V

3.3V AND 5V STEP-DOWN CONTROLLERS

INTERNAL REGULATOR AND REFERENCE

COMPARATORS