1

LTC1144

Switched-Capacitor

Wide Input Range

Voltage Converter

with Shutdown

APPLICATI

TYPICAL

S

FEATURE

DESCRIPTIO

s

Wide Operating Supply Voltage Range: 2V to 18V

s

Boost Pin (Pin 1) for Higher Switching Frequency

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Simple Conversion of 15V to –15V Supply

s

Low Output Resistance: 120

Ω Maximum

s

Power Shutdown to 8

µA with SHDN Pin

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Open Circuit Voltage Conversion Efficiency:

99.9% Typical

s

Power Conversion Efficiency: 93% Typical

s

Easy to Use

The LTC1144 is a monolithic CMOS switched-capacitor

voltage converter. It performs supply voltage conversion

from positive to negative from an input range of 2V to 18V,

resulting in complementary output voltages of –2V to

–18V. Only two noncritical external capacitors are needed

for the charge pump and charge reservoir functions.

The converter has an internal oscillator that can be

overdriven by an external clock or slowed down when

connected to a capacitor. The oscillator runs at a 10kHz

frequency when unloaded. A higher frequency outside the

audio band can also be obtained if the Boost Pin is tied to

µA and can

be used to save power when the converter is not in use.

The LTC1144 contains an internal oscillator, divide-by-

two, voltage level shifter, and four power MOSFETs. A

special logic circuit will prevent the power N-channel

switch substrate from turning on.

S

APPLICATI

s

Conversion of 15V to

±15V Supplies

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Inexpensive Negative Supplies

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Data Acquisition Systems

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High Voltage Upgrade to LTC1044 or 7660

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Voltage Division and Multiplications

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Automotive Applications

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Battery Systems with Wall Adapter/Charger

LOAD CURRENT (mA)

010

–15

–14

–13

–12

–11

–10

40

1144 TA02

20

30

50

1

2

3

4

8

7

6

5

BOOST

GND

OSC

SHDN

+

10

µF

–15V OUTPUT

15V INPUT

LTC1144

10

µF

1144 TA01

Generating –15V from 15V