28V, Low-Power, High-Voltage,

Boost or Inverting DC-DC Converter

2

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ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

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.

SHDN to GND...........................................................-0.3V to +6V

LX to GND ..............................................................-0.3V to +30V

SO (derate 5.88mW/°C above +70°C) ..........................471mW

Operating Temperature Range ...........................-40°C to +85°C

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

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

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

CONDITIONS

V

2.7

5.5

UNITS

MIN

TYP

MAX

PARAMETER

µA

80

120

100mV hysteresis

V

2.3

2.5

2.65

SHDN = GND

µA

0.04

1

A

0.39

0.45

0.51

Circuit of Figure 2

µA

0.05

2.5

LX Leakage Current

POL = GND

µs

0.7

1.0

1.3

Minimum LX Off-Time

µs

6.5

8.5

10.0

Maximum LX On-Time

0.20

0.25

0.33

LX Switch-Current Limit

V

28

Positive Output Voltage

3.0

4.5

6.0

2.0

3.2

3.8

POL = GND

(positive output)

V

1.218

1.282

1.225

1.250

1.275

nA

5

50

FB Input Bias Current

1.225

1.250

1.275

Ω

0.6

1.2

0.7

1.4

LX On-Resistance

(negative output)

mV

-25

25

FB Set Point

-15

0

15

no load on REF

V

1.218

1.282

REF Output Voltage

V

2.4

SHDN, POL, ISET Logic Levels

0.4

V

0.8

Input Supply Voltage (Note 2)

Circuit of Figure 3

V

-

-28

Negative Output Voltage

ISET = GND

3.0

4.5

6.0