LK112Sxx
Low noise low drop voltage regulator with shutdown function
Features
■
■
■
Output current up to 200 mA
Low dropout voltage (500 mV max at
I
OUT
= 200 mA)
Very low quiescent current: 0.1 µA in OFF
mode and max 250 µA in ON mode at
I
OUT
= 0 mA
Low output noise: typ. 30 µV at I
OUT
= 60 mA
and 10 Hz < f < 80 kHz
Wide range of output voltages
Internal current and thermal limit
V
OUT
tolerance ± 2% (at 25 °C)
Operative input voltage from:
V
OUT
+ 0.5 to 14 V (for V
OUT
> 2 V)
or from 2.5 V to 14 V (for V
OUT
< 2 V)
µVrms. An internal PNP pass transistor is used to
achieve a low dropout voltage.
The LK112Sxx has a very low quiescent current
in ON MODE while in OFF MODE the Iq is
reduced down to 100 nA max. The internal
thermal shutdown circuitry limits the junction
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.
SOT23-5L
■
■
■
■
■
Description
The LK112Sxx 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 30
Table 1.
Device summary
Part numbers
LK112SXX13
LK112SXX14
LK112SXX18
LK112SXX19
LK112SXX20
LK112SXX21
LK112SXX22
LK112SXX23
July 2008
LK112SXX24
LK112SXX26
LK112SXX28
LK112SXX29
LK112SXX31
LK112SXX33
LK112SXX34
LK112SXX35
Rev 11
LK112SXX36
LK112SXX37
LK112SXX38
LK112SXX39
LK112SXX41
LK112SXX42
LK112SXX43
LK112SXX44
LK112SXX45
LK112SXX46
LK112SXX47
LK112SXX48
LK112SXX49
LK112SXX50
1/17
www.st.com
17
Contents
LK112Sxx
Contents
1
2
3
4
5
6
7
8
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Order codes
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2/17
Pin configuration
LK112Sxx
2
Figure 2.
Pin configuration
Pin connection (top view)
Table 2.
Pin n°
1
2
3
4
5
Pin description
Symbol
SHDN
GND
Bypass
OUT
IN
Note
Shutdown Input: Disables the regulator when is connected to GND or to positive
voltage less than 0.6 V
Ground Pin: Internally connected to the die attach flag to decrease the total thermal
resistance and increase the package ability to dissipate power.
Bypass Pin: Bypass with 0.1 µF to improve the V
REF
thermal noise performances.
Output port
Input port
4/17
LK112Sxx
Maximum ratings
3
Table 3.
Maximum ratings
Absolute maximum ratings
Parameter
DC input voltage
DC input voltage
Output current
Storage temperature range
Operating junction temperature range
Value
16
16
Internally limited
-55 to 150
-40 to 125
°C
°C
Unit
V
V
Symbol
V
I
V
SHDN
I
O
T
STG
T
OP
Table 4.
Symbol
R
thJC
R
thJA
Thermal data
Parameter
Thermal resistance junction-case
Thermal resistance junction-ambient
SOT23-5L
81
255
Unit
°C/W
°C/W
5/17