Datasheet
1
LTC1754-3.3/LTC1754-5
Micropower, Regulated
3.3V/5V Charge Pump with
Shutdown in SOT-23
■
Ultralow Power: I
IN
= 13
µ
A
■
Regulated Output Voltage: 3.3V
±
4%, 5V
±
4%
■
5V Output Current: 50mA (V
IN
≥
3.0V)
■
3.3V Output Current: 40mA (V
IN
≥
2.5V)
■
No Inductors Needed
■
Very Low Shutdown Current: <1µA
■
Shutdown Disconnects Load from V
IN
■
Internal Oscillator: 600kHz
■
Short-Circuit and Overtemperature Protected
■
Ultrasmall Application Circuit: (0.052 Inch
2
)
■
6-Pin SOT-23 Package
■
SIM Interface Supplies for GSM Cellular Telephones
■
White LED Power Supplies
■
Li-Ion Battery Backup Supplies
■
Handheld Computers
■
Smart Card Readers
■
PCMCIA Local 5V Supplies
The LTC
®
1754 is a micropower charge pump DC/DC
converter that produces a regulated output. The input
voltage range is 2V to 4.4V for 3.3V output and 2.7V to
5.5V for 5V output. Extremely low operating current and a
low external parts count (one flying capacitor and two
small bypass capacitors at V
IN
and V
OUT
) make the LTC1754
ideally suited for small, battery-powered applications. The
total component area of the application circuit shown
below is only 0.052 inch
2
.
The LTC1754 operates as a Burst Mode
TM
switched capaci-
tor voltage doubler to produce a regulated output. It has
thermal shutdown capability and can survive a continuous
short circuit from V
OUT
to GND.
The LTC1754 is available in a 6-pin SOT-23 package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Burst Mode is a trademark of Linear Technology Corporation.
LTC1754-5
Output Voltage vs Supply Voltage
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
SUPPLY VOLTAGE (V)
2.5
4.85
OUTPUT VOLTAGE (V)
4.90
4.95
5.00
5.05
5.15
3.0
3.5 4.0 4.5
1574 TA03
5.0 5.5
5.10
T
A
= –40°C
T
A
= 85°C
I
OUT
= 25mA
C
OUT
= 10µF
C
FLY
= 1µF
T
A
= 25°C
SUPPLY VOLTAGE (V)
2.0
OUTPUT VOLTAGE (V)
3.30
3.35
4.0
1754 TA02
3.25
3.20
2.5
3.0
3.5
4.5
3.40
I
OUT
= 20mA
C
OUT
= 10µf
C
FLY
= 1µF
T
A
= 85°C
T
A
= 25°C
T
A
= –40°C
LTC1754-3.3
Output Voltage vs Supply Voltage
1
LTC1754-X
Regulated 3.3V Output from 2V to 4.4V Input
Regulated 5V Output from 2.7V to 5.5V Input
2
3
6
5
4
ON/OFF
V
OUT
1754 TA01
V
IN
V
OUT
V
OUT
= 5V ±4%
I
OUT
= 0mA TO 25mA, V
IN
> 2.7V
I
OUT
= 0mA TO 50mA, V
IN
> 3.0V
10µF
1µF
10µF
GND
SHDN
C
+
V
IN
C
–
V
OUT
= 3.3V ±4%
I
OUT
= 0mA TO 20mA, V
IN
> 2.0V
I
OUT
= 0mA TO 40mA, V
IN
> 2.5V