LTC1516 Datasheet, PDF (1/8 Pages) Linear Technology – Micropower, Regulated 5V Charge Pump DC/DC Converter

FEATURES
s _{Ultralow Power: Typical Operating ICC = 12µA}
s _{Short Circuit/Thermal Protection}
s _{Regulated 5V ±4% Output}
s _{2V to 5V Input Range}
s _{No Inductors}
s _{ICC in Shutdown: < 1µA}
s _{Output Current: 20mA (VIN > 2V)}
50mA (V_IN > 3V)
s _{Shutdown Disconnects Load from VIN}
s _{Internal Oscillator: 600kHz}
s _{Compact Application Circuit (0.1 in}²₎
s _{8-Pin SO Package}
U
APPLICATIONS
s _{2-Cell to 5V Conversion}
s _{Li-Ion Battery Backup Supplies}
s _{Local 3V to 5V Conversion}
s _{5V Flash Memory Programmer}
s _{Smart Card Readers}
LTC1516
Micropower, Regulated
5V Charge Pump
DC/DC Converter
DESCRIPTION
The LTC^®1516 is a micropower charge pump DC/DC
converter that produces a regulated 5V output from a 2V
to 5V supply. Extremely low supply current (12µA typical
with no load, < 1µA in shutdown) and low external parts
count (two 0.22µF flying capacitors and two 10µF capaci-
tors at V_IN and V_OUT) make the LTC1516 ideally suited for
small, light load battery-powered applications. Typical
efficiency (V_IN = 3V) exceeds 70% with load currents
between 50µA and 50mA. Modulating the SHDN pin keeps
the typical efficiency above 70% with load currents all the
way down to 10µA.
The LTC1516 operates as either a doubler or a tripler
depending on V_IN and output load conditions to improve
overall efficiency. The part has thermal shutdown and can
survive a continuous short from V_OUT to GND. In shut-
down the load is disconnected from V_IN.
The LTC1516 is available in an 8-pin SO package in both
commercial and industrial temperature grades.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATION
0.22µF
1 _C1+
C1^{– 8}
V_IN = 2V TO 5V ₊
10µF
+
2 _VIN
SHDN ⁷
LTC1516
3 _VOUT
GND ⁶
10µF _{4 C2+}
C2^{– 5}
0.22µF
ON/OFF
V_OUT = 5V ±4%
I_OUT = 0mA TO 20mA, V_IN ≥ 2V
I_OUT = 0mA TO 50mA, V_IN ≥ 3V
1516 • F01
Figure 1. Regulated 5V Output from a 2V to 5V Input
Efficiency vs Output Current
90
V_IN = 3V
80
LOW I_Q MODE
70
(SEE FIGURE 3)
SHDN = 0V
60
50
0.01
0.1
1
10
OUTPUT CURRENT (mA)
100
1516 • TA01
1