High-Efficiency, Step-Up

DC-DC Converters for 1V Inputs

2

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ABSOLUTE MAXIMUM RATINGS

BATT to GND ...........................................................-0.3V to 6.0V

BATT Forward Current ..........................................................0.5A

OUT to GND.............................................................-0.3V to 6.0V

OUT, LX Current.......................................................................1A

LX to GND................................................................-0.3V to 6.0V

SHDN, FB, BATTLO, PFO to GND ...........................-0.3V to 6.0V

Continuous Power Dissipation

µMAX (derate 4.1mW/°C above 70°C)..........................330mW

Operating Temperature Range

MAX1642EUA/MAX1643EUA ............................-40°C to +85°C

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

Storage Temperature Range .............................-65°C to +165°C

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

External feedback

External feedback

CONDITIONS

nA

10

FB Input Current

%

80

η

Efficiency

µA

2

3.5

Shutdown Current into BATT

µA

0.1

1

Shutdown Current into OUT

µA

4

6.5

Quiescent Current into BATT

µA

11

18

Quiescent Current into OUT

1

1.5

RATIO

Off-Time Tracking Ratio (Note 3)

mV/°C

-2

Start-Up Voltage Tempco

V

0.88

V

0.7

Minimum Operating Input Voltage

Start-Up Voltage (Note 2)

V-µs

17

25

35

K

On-Time Constant

V

0.8

P-Channel Catch-Diode Voltage

Ω

1.5

2.2

P-Channel On-Resistance

V

3.16

3.30

3.44

Output Voltage

V

2.0

5.2

Output Voltage Range

V

1.18

1.225

1.27

FB Set Voltage

Ω

1

1.5

N-Channel On-Resistance

UNITS

MIN

TYP

MAX

SYMBOL

PARAMETER

ELECTRICAL CHARACTERISTICS

Note 1: The reverse battery current is measured from the

Typical Operating Circuit’s input terminal to GND when the battery is con-

nected backward. A reverse current of 220mA will not exceed package dissipation limits but, if left for an extended time

(more than 10 minutes), may degrade performance.

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

1.65

Maximum Operating Input Voltage

Falling PFI, hysteresis = 1%

mV

590

614

632

PFI Trip Voltage

V

0.4

PFO, BATTLO Low Output Voltage

nA

10

PFI Input Current

V

0.96

1.0

1.04

BATTLO Trip Voltage

µA

1

PFO, BATTLO Leakage Current

%

80

SHDN Input High Voltage

%

20

SHDN Input Low Voltage

(MAX1642)

nA

10

SHDN Input Current