Datasheet

1
LTC1517-5
TYPICAL APPLICATION
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Micropower, Regulated
5V Charge Pump in a
5-Pin SOT-23 Package
■
Ultralow Power: I
CC
= 6 µ A Typ
■
Short-Circuit/Thermal Protected
■
5V ±4% Regulated Output
■
V
IN
Range: 2.7V to 5V
■
Output Current: 10mA (V
IN
≥ 2.7V)
20mA (V
IN
≥ 3V)
■
No Inductors
■
Ultrasmall Application Circuit (0.045in
2
)
■
800kHz Switching Frequency
■
Available in 5-Pin SOT-23
FEATURES
DESCRIPTION
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The LTC
®
1517-5 is a micropower charge pump DC/DC
converter that produces a regulated 5V output. The input
voltage range is 2.7V to 5V. Extremely low operating current
(typically 6µA with no load) and low external parts count (one
0.1µF flying capacitor and two small bypass capacitors at V
IN
and V
OUT
) make the part ideally suited for small, light load
battery-powered applications. The total printed circuit board
area of the application circuit shown below is only 0.045in
2
.
The part operates as a Burst Mode
TM
switched-capacitor
voltage doubler to produce a regulated output. The part has
thermal shutdown capability and can survive a continuous
short circuit from V
OUT
to GND. The device is available in a
5-pin SOT-23 package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Burst Mode is a trademark of Linear Technology Corporation.
OUTPUT CURRENT (mA)
0
OUTPUT VOLTAGE (V)
5.0
5.1
80
1517 TA02
4.9
4.8
20
40
60
5.2
V
IN
= 3.3V
V
IN
= 3V
V
IN
= 2.7V
T
A
= 25°C
C1 = 0.1µF
C
OUT
= 6.8µF
Typical Output Voltage vs Output Current
3.3µF
1517 TA01
123
4
5
0.1µF
6.8µF
V
OUT
= 5V ± 4%
I
OUT
= 10mA (V
IN
≥ 2.7V)
I
OUT
= 20mA (V
IN
≥ 3V)
V
IN
2.7V TO 5V
V
IN
GND
LTC1517-5
V
OUT
C1
+
C1
–
■
Cellular Telephones
■
Battery-Operated Equipment
■
Local Power Supplies
■
Handheld Instruments
■
PCMCIA Supplies
APPLICATIONS
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