500kHz Multi-Output, Low-Noise Power-Supply

Controllers for Notebook Computers

6

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ELECTRICAL CHARACTERISTICS (continued)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

V+ Standby Supply Current

V+ = 5.5V to 30V, both SMPSs off, includes

current into

SHDN

60

µA

V+ Standby Supply Current in Dropout

V+ = 4.2V to 5.5V, both SMPSs off, includes

current into

SHDN

200

µA

V+ Shutdown Supply Current

V+ = 4.0V to 30V,

SHDN = 0

10

µA

(Note 3)

4

Quiescent Power Consumption

Both SMPSs enabled,

FB3 = FB5 = 0,

CSL3 = CSH3 = 3.5V,

CSL5 = CSH5 = 5.3V

MAX1901/MAX1904

4

mW

FAULT DETECTION (MAX1901/MAX1902)

Overvoltage Trip Threshold

With respect to unloaded output voltage

4

10

%

Output Undervoltage Threshold

With respect to unloaded output voltage

60

80

%

Output Undervoltage Lockout Time

From each SMPS enabled, with respect to

5,000

7,000

clks

RESET

RESET Trip Threshold

With respect to unloaded output voltage,

falling edge; typical hysteresis = 1%

-7

-4

RESET Delay Time

27,000

37,000

%

clks

INPUTS AND OUTPUTS

Feedback-Input Leakage Current

FB3, FB5; SECFB = 2.6V

50

nA

Logic Input-Low Voltage

RUN/ON3,

SKIP, TIME/ON5 (SEQ = REF),

SHDN, STEER, SYNC

0.6

V

Logic Input-High Voltage

RUN/ON3,

SKIP, TIME/ON5 (SEQ = REF),

SHDN, STEER, SYNC

2.4

V

Logic Output-Low Voltage

0.4

V

Logic Output-High Current

RESET = 3.5V

1

mA

TIME/ON5 Input Trip Level

2.4

2.6

V

TIME/ON5 Source Current

2.5

3.5

µA

TIME/ON5 On-Resistance

80

Ω

SSOP package

7

Gate-Driver On-Resistance

High or low (Note 6)

QFN package

8

Ω

Note 1: Each of the four digital soft-start levels is tested for functionality; the steps are typically in 20mV increments.

Note 2: High duty-factor operation supports low input-to-output differential voltages, and is achieved at a lowered operating frequency

(see the Dropout Operation section).

Note 3: MAX1902 only.

tions where the main outputs are being held up by external keep-alive supplies, turning off the 12OUT regulator prevents a leak-

Note 6: Production testing limitations due to package handing require relaxed maximum on-resistance specifications for the thin

QFN package. The SSOP and thin QFN package contain the same die, and the thin QFN package imposes no additional

resistance incircuit.

Note 7: Specifications from to 0°C to -40°C are guaranteed by design, not production tested.