FEATURES
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LTC3261
High Voltage,
Low Quiescent Current
Inverting Charge Pump
DESCRIPTION
The LTC
®
3261 is a high voltage inverting charge pump
that operates over a wide 4.5V to 32V input range and
is capable of delivering up to 100mA of output current.
The charge pump employs either low quiescent current
Burst Mode operation or low noise constant frequency
mode. In Burst Mode operation the charge pump V
OUT
regulates to –0.94 • V
IN
and the LTC3261 draws only 60μA
of quiescent current. In constant frequency mode the charge
pump produces an output equal to –V
IN
and operates at
a fixed 500kHz or to a programmed frequency between
50kHz to 500kHz using an external resistor. The LTC3261
is available in a thermally enhanced 12-pin MSOP package.
L,
LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
4.5V to 32V V
IN
Range
Inverting Charge Pump Generates –V
IN
60μA Quiescent Current in Burst Mode
®
Operation
Charge Pump Output Current Up to 100mA
50kHz to 500kHz Programmable Oscillator
Frequency
Short-Circuit/Thermal Protection
Low Profile Thermally Enhanced 12-Pin MSOP
Package
APPLICATIONS
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Bipolar/Inverting Supplies
Industrial/Instrumentation Bias Generators
Portable Medical Equipment
Portable Instruments
TYPICAL APPLICATION
15V to –15V Inverter
1μF
V
OUT
Ripple
C
+
15V
10μF
LTC3261
EN
MODE
GND
100μs/DIV
3261 TA01
C
–
V
OUT
10μF
–15V
V
OUT
10mV/DIV
AC-COUPLED
MODE = L
V
OUT
= –14.8V
V
IN
RT
V
OUT
200mV/DIV
AC-COUPLED
MODE = H
V
OUT
= –14.1V
3261 TA01a
V
IN
= 15V
f
OSC
= 500kHz
I
OUT
= 5mA
3261f
1
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
