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STMicroelectronics |
LK112
SERIES
LOW NOISE LOW DROP VOLTAGE REGULATOR
WITH SHUTDOWN FUNCTION
s OUTPUT CURRENT UP TO 150mA
s LOW DROPOUT VOLTAGE (350mV AT
IOUT=150mA)
s VERY LOW QUIESCENT CURRENT: 0.1µA
IN OFF MODE AND MAX 250µA IN ON
MODE AT IOUT=0mA
s LOW OUTPUT NOISE: TYP 30µV AT
IOUT=60mA AND 10Hz<f<80KHz
s WIDE RANGE OF OUTPUT VOLTGAES
s INTERNAL CURRENT AND THERMAL LIMIT
DESCRIPTION
The LK112 is a low dropout linear regulator with a
built in electronic switch. The internal switch can
be controlled by TTL or CMOS logic levels. The
device is ON state when the control pin is pulled to
a logic high level. An external capacitor can be
used connected to the noise bypass pin to lower
the output noise level to 30µVrms. An internal PNP
pass transistor is used to achieve a low dropout
voltage.
SOT23-5L
The LK112 has a very low quiescent current in ON
MODE while in OFF MODE the Iq is reduced
down to 100nA max. The internal thermal
shutdown circuitry limits the juntion temperature to
below 150°C. The load current is internally
monitored and the device will shutdown in the
presence of a short circuit or overcurrent condition
at the output.
SCHEMATIC DIAGRAM
June 2003
1/12
LK112 SERIES
ABSOLUTE MAXIMUM RATINGS
Symbol
VI
VSHDN
IO
Tstg
Top
Parameter²
DC Input Voltage
Shutdown Input Voltage
Output Current
Storage Temperature Range
Operating Junction Temperature Range
THERMAL DATA
Symbol
Parameter
Rthj-case Thermal Resistance Junction-case
Rthj-amb Thermal Resistance Junction-ambient
CONNECTION DIAGRAM (top view)
SOT23-5L
Value
16
16
Internally limited
-55 to +150
-30 to +125
Unit
V
V
°C
°C
SOT23-5L
81
255
Unit
°C/W
°C/W
PIN DESCRIPTION
Pin N° Symbol
Name and Function
1 SHDN Shutdown Input: Disables the
regulator when is connected to GND
or to positive voltage less than 0.6V
2 GND Ground Pin: Internally connected to
the die attach flag to decrease the
total thermal resistance and increase
the package ability to dissipate
power.
3 Bypass Bypass Pin: Bypass with 0.1µF to
improve the Vref thermal noise
performances.
4 OUT Output Port
5 IN Input Port
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