LMS5258
150mA, Cap, Low Dropout Voltage Regulator with
Power Good
General Description
The LMS5258 is a Cap, precise CMOS voltage regulator
with power good output.
It provides up to 150mA and consumes a typical of 10nA in
shutdown mode. The LMS5258 output stage is designed
with a push pull output for faster transient response.
The LMS5258 is optimized to work with low value, low cost
ceramic capacitors. The output typically require only 1F of
output capacitance for stability. The enable pin can be tied to
V
IN
for easy device layout.
The LMS5258 is designed for portable, battery powered
equipment applications with small space requirements.
The LMS5258 is available in a 5-pin SOT-23 package. Per-
formance is specified for the -40C to +125C temperature
range and is available in a fixed 1.2V. For other output
voltage options, please contact National Semiconductor.
Features
n
Power good indicator
n
Stability with low ESR capacitors
n
Low ground current: 120A
n
150mA output current
n
"Zero" shutdown mode current
n
Fast transient response
n
Auto Discharge
n
Thermal shutdown
n
Current limiting
n
TTL-Logic-controlled enable input
n
Pin-to-pin replacement for Mic
TM
5258
Applications
n
Processor power-up sequencing
n
Laptop, notebook and palm top computer
n
PCMCIA V
CC
and V
PP
regulation switching
Typical Application
20042419
Pin Description
Pin Number
Pin Name
Pin Function
1
V
IN
Input Voltage
2
GND
Ground
3
EN
Enable Input Logic,
Logic High = Enabled
Logic Low = Shutdown
(Do not leave open)
4
PG
Power Good Output
5
V
OUT
Output Voltage
February 2003
LMS5258
150mA,
Cap,
Low
Dropout
V
oltage
Regulator
with
Power
Good
2003 National Semiconductor Corporation
DS200424
www.national.com
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
ESD Tolerance (Note 2)
Human Body Model
2000V
Junction Temperature
150C
V
IN
, V
OUT
, V
EN
-0.3 TO 6.5V
Soldering Information
Infrared or Convection (20 sec)
235C
Wave Soldering (10 sec)
260C (lead temp)
Operating Ratings
Supply Voltages
V
IN
2.7V to 6V
V
EN
0V to V
IN
Junction Temp. Range (Note 3)
-40C to +125C
Storage Temperature Range
-65C to 150C
Package Themal Resistance
SOT23-5
235C/W
Electrical Characteristics
Unless otherwise specified, all limits guaranteed for T
J
= 25C, V
IN
= 2.7V, I
L
= 100A, C
OUT
= 1F, V
EN
2.0V. Boldface
limits apply over the entire operating temperature range, -40C to 125C.
Symbol
Parameter
Conditions
Min
(Note 5)
Typ
(Note 4)
Max
(Note 5)
Units
V
O
Output Voltage Accuracy
-3
-4
3
4
%
V
O
/V
O
Line Regulation
V
IN
= 2.7V to 6V
-0.3
0.3
%
V
O
/V
O
Load Regulation
I
L
= 0.1mA to 150mA (Note 6)
1
4
%
I
Q
Quiescent Current
V
EN
0.4V (Shutdown), PG = NC
.01
1
A
I
GND
Ground Pin Current (Note 5)
V
EN
2.0V (active),
V
IN
= 6V, I
L
= 0mA
120
180
A
I
L
= 150mA, V
EN
2.0V (active),
V
IN
= 6V
160
225
PSRR
Power Supply Rejection
f = 120H
Z
, C
OUT
= 4.7F,
I
L
= 150mA
62
dB
I
LIMIT
Current Limit
V
OUT
= 0V
160
350
mA
Thermal Protection
Thermal Shutdown
Temperature
150
C
Enable Input
V
IL
Enable Input Voltage Level
Logic Low (off), V
IN
= 5.5V
0.4
V
V
IH
Logic High (on), V
IN
= 5.5V
2
V
I
IL
Enable Input Current
V
IL
0.4V, V
IN
= 5.5V
0.01
A
I
IH
V
IH
2.0V, V
IN
= 5.5V
0.01
A
Power Good
V
PG
Low Threshold
% of V
OUT
(PG ON)
89
%
High Threshold
% of V
OUT
(PG OFF)
97
V
OL
PG Output Logic-Low
Voltage
Ipowergood = 100A, Fault
Condition
0.02
0.1
V
I
PG
Power Good Leakage
Current
Power Good Off, V
PG
= 5.5V
0.01
A
V
PG
Delay
Delay Time to Power Good
See Timing Diagram
1
5
ms
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 2: Human body model, 1.5k
in series with 100pF.
Note 3: The maximum power dissipation is a function of T
J(MAX)
,
JA
, and T
A
. The maximum allowable power dissipation at any ambient temperature
is P
D
= (T
J(MAX)
T
A
)/
JA
. All numbers apply for packages soldered directly into a PC board.
Note 4: Typical Values represent the most likely parametric norm.
Note 5: All limits are guaranteed by testing or statistical analysis.
Note 6: Regulation is measured at constant junction temperature using low duty cycle pulse testing.
Note 7: Ground pin current is the regulator quiescent current. The total current drawn from the supply is the sum of the load current plus the ground pin current.
LMS5258
www.national.com
3
Typical Performance Characteristics
Unless otherwise specified, V
IN
= 3.3V, C
OUT
= 1F, T
A
=
25C and powergood pull up resistor = 47k
.
Ground Current vs. Output Current
Ground Current vs. Input Voltage
20042401
20042402
Ground Current vs. Temperature
Short Circuit Current vs. Temperature (V
IN
= 3.3V)
20042403
20042404
Short Circuit Current vs. Input Voltage
Power Good Delay vs. Input Voltage (I
L
= 100A)
20042405
20042406
LMS5258
www.national.com
5
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