5-Channel Slim DSC Power Supplies

6

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PARAMETER

CONDITIONS

MIN

MAX

UNITS

FBSD Regulation Voltage

1.225

1.275

V

FBSD to CCSD

Transconductance

FBSD = CCSD

80

185

µS

FBSD Input Leakage Current

FBSD = 1.25V

-100

+100

nA

LXSD Leakage Current

5

µA

N channel

150

Switch On-Resistance

P channel

250

m

Ω

P-Channel Current Limit

0.65

0.95

A

SDOK Output Low Voltage

0.1mA into

SDOK

0.1

V

SDOK Leakage Current

ONSU = GND

1

µA

AUX1, 2, 3 DC-DC CONTROLLERS

Maximum Duty Cycle

FB_ = 1V

80

90

%

FB1 and FB3 Regulation Voltage

FB_ = CC_

1.225

1.275

V

FB2 (MAX1584) Regulation

Voltage

FB_ = CC_

1.225

1.275

V

FB2 (MAX1585) (Inverter)

Regulation Voltage

FB_ = CC_

-0.01

+0.01

V

FB_ to CC_ Transconductance

FB_ = CC_

80

185

µS

FB_ Input Leakage Current

FB_ = 1.25V

-100

+100

nA

DL_ Driver Resistance

Output high or low

10

Ω

AUX1OK Output Low Voltage

0.1mA into

AUX1OK

0.1

V

AUX1OK Leakage Current

ONSU = GND

1

µA

OVERLOAD AND THERMAL PROTECTION

SCF Leakage Current

ONSU = PVSU, FBSU = 1.5V

1

µA

SCF Output Low Voltage

0.1mA into SCF

0.1

V

LOGIC INPUTS

1.1V < PVSU < 1.8V (ONSU only)

0.2

ON_ Input Low Level

1.8V < PVSU < 5.5V

0.4

V

1.1V < PVSU < 1.8V (ONSU only)

ON_ Input High Level

1.8V < PVSU < 5.5V

1.6

V

ELECTRICAL CHARACTERISTICS (continued)

Note 2: The MAX1584/MAX1585 are powered from the step-up output (PVSU). An internal low-voltage startup oscillator drives the

step-up starting at about 0.9V until PVSU reaches approximately 2.5V. When PVSU reaches 2.5V, the main control circuitry

takes over. Once the step-up is up and running, it can maintain operation with very low input voltages; however, output cur-

rent is limited.

Note 3: Since the device is powered from PVSU, a Schottky rectifier, connected from the input battery to PVSU, is required for low-

Note 4: The step-up regulator is in startup mode until this voltage is reached. Do not apply full load current during startup. A power-

OK output can be used with an external PFET to gate the load until the step-up is in regulation. See the Applications

Information section.