LTC1502-3.3_15 Datasheet, PDF (1/8 Pages) Linear Technology – Single Cell to 3.3V Regulated Charge Pump DC/DC Converter

FEATURES
s _{Input Voltage Range: 0.9V to 1.8V}
s _{0.9V Guaranteed Start-Up Voltage}
s _{Regulated Output Voltage: 3.3V ±4%}
s _{Output Current: 10mA (VIN ≥ 1V)}
s _{No Inductors}
s _{Shutdown Disconnects Load from VIN}
s _{Low Operating Current: 40µA}
s _{Low Shutdown Current: 5µA}
s _{Short-Circuit and Overtemperature Protected}
s _{Application Circuit Fits in < 0.125in}² _{PCB Area}
s _{Available in 8-Pin MSOP and SO Packages}
U
APPLICATIO S
s _Pagers
s _{Battery Backup Supplies}
s _{Portable Electronic Equipment}
s _{Handheld Medical Instruments}
s _{Glucose Meters}
LTC1502-3.3
Single Cell to 3.3V
Regulated Charge Pump
DC/DC Converter
DESCRIPTIO
The LTC^®1502-3.3 is a quadrupler charge pump DC/DC
converter that produces a regulated 3.3V output from a
single alkaline cell input. It requires only five small external
capacitors—no inductors are required. Low supply cur-
rent (40µA typical, 5µA in shutdown) and minimal external
components make the LTC1502-3.3 ideal for space and
power conscious single-cell applications. The total printed
circuit board area of the circuit shown below is less than
0.125in².
Forcing the C1^–/SHDN pin low through an external resis-
tive pull-down puts the part into shutdown mode. During
shutdown, the internal oscillator is stopped and the load is
disconnected from V_IN. An internal pull-up current on the
C1^–/SHDN pin forces the part back into normal operation
once the pull-down resistance is removed.
The LTC1502-3.3 is short-circuit protected and survives
an indefinite V_OUT short to ground. The LTC1502-3.3 is
available in 8-pin MSOP and SO packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
Single Cell to 3.3V DC/DC Converter
10µF
1
C2
2 _C1+
8
V_OUT
C3^{+ 7}
1µF ₃
LTC1502-3.3
C1^–/SHDN C3 ^–
6
4
GND
5
V_IN
1µF
10µF
V_OUT = 3.3V
10µF ^{IOUT = 10mA}
V_IN
SINGLE CELL
NiCd or
ALKALINE
1502-3.3 TA01
PCB LAYOUT FITS IN < 0.125IN²
Output Voltage vs Input Voltage
3.5
T_A = 25°C
3.4
3.3
3.2
I_OUT = 10mA
I_OUT = 15mA
3.1
3.0
0.8
1.0 1.2 1.4 1.6 1.8
INPUT VOLTAGE (V)
1502-3.3 TA02
1