If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
V
IN
pin: Voltage to GND
EN pin: Voltage to GND
Continuous Power Dissipation
(Note 3)
Junction Temperature (T
J-MAX
)
Storage Temperature Range
Package Peak Reflow Temperature
(10-20 sec.)
Package Peak Reflow Temperature
(Pb-free, 10-20 sec.)
ESD Rating(Note 4)
Human Body Model:
Machine Model
-0.3V to 6.5V
-0.3V to (V
IN
+0.3V)
with 6.5V max
Internally Limited
150°C
-65°C to + 150°C
240°C
260°C
2.0kV
200V
Operating Ratings
(Notes 1, 2)
Input Voltage Range (V
IN
)
V
EN
Input Voltage
Junction Temperature (T
J
) Range
Ambient Temperature (T
A
) Range
1.8V to 5.5V
0 to (V
IN
+ 0.3V)
-40°C to + 125°C
(Note 5)
Thermal Properties
Junction-to-Ambient Thermal
Resistance (θ
JA
), (Note 6)
SOT23-5 Package:
SC70-5 Package:
220°C/W
415°C/W
ESD Caution Notice
National Semiconductor recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper
ESD handling techniques can result in damage.
Electrical Characteristics
(Notes 2, 7)
Typical values and limits appearing in standard typeface are for T
A
= 25°C. Limits appearing in
boldface
type apply over the full
operating temperature range: -40°C
≤
T
J
≤
+125°C. Unless otherwise noted, V
IN
= V
OUT(NOM)
+ 1V, C
IN
= 1µF, C
OUT
= 1µF, V
EN
=
0.9V.
Symbol
V
IN
Parameter
Input Voltage
Output Voltage
Tolerance
ΔV
OUT
Line Regulation Error
Load Regulation Error
V
DO
Condition
V
IN
≥
V
OUT(NOM)
+ V
DO
I
OUT
= 1mA
-30°C
≤
T
J
≤
+125°C
V
IN
= V
OUT(NOM)
+ 1V to 5.5V
I
OUT
= 1mA
I
OUT
= 1mA to 150mA
0.1
-0.01
Typ
Min
1.8
-2.0
-3.5
Limit
Max
5.5
2.0
3.5
V
%
%
%/V
%/mA
Units
Output Voltage Dropout I
OUT
= 150mA
(Note 10)
V
OUT
≥
2.5V
V
OUT
< 2.5V
Quiescent Current
V
EN
= 0.9V, I
LOAD
= 0
V
EN
= 0.9V, I
LOAD
= 150mA
V
EN
= 0V
V
IN
= V
OUT(NOM)
+ 1V
Sine modulated V
IN
f = 100Hz
f = 1kHz
f = 10kHz
BW = 10Hz - 100kHz
200
29
33
0.005
400
150
250
350
55
70
1
mV
mV
µA
µA
µA
mA
I
Q
I
SC
PSRR
Output Current
(short circuit)
Power Supply
Rejection Ratio
60
60
50
125
160
20
dB
dB
dB
µV
RMS
°C
°C
E
N
TSD
Output Noise
Thermal Shutdown
Temperature Hysteresis
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LP5951
Enable Control Characteristics
Symbol
I
EN
V
IL
V
IH
Parameter
Conditions
Typical
Min
Maximum Input Current 0V
≤
V
EN
≤
V
IN
, V
IN
= 5.5V
at V
EN
Input
Low Input Threshold
(shutdown)
High Input Threshold
(enable)
V
IN
= 1.8..5.5V
V
IN
= 1.8..5.5V
0.9
-1
Limit
Max
1
0.4
µA
V
V
Units
Transient Characteristics
Symbol
ΔV
OUT
ΔV
OUT
Parameter
Dynamic Line
Transient
Dynamic Load
Transient
Conditions
V
IN
= V
OUT(NOM)
+ 1V to
V
OUT(NOM)
+ 1V + 0.6V in 30µs, no load
I
OUT
= 0mA to 150mA in 10µs
I
OUT
= 150mA to 0mA in 10µs
I
OUT
= 1mA to 150mA in 1µs
I
OUT
= 150mA to 1mA in 1µs
I
OUT
= 1mA
Typical
Min
±2
-30
20
-50
40
10
30
Limit
Max
mV
mV
mV
mV
mV
mV
µs
Units
ΔV
OUT
T
ON
Overshoot on Startup Nominal conditions
Turn on time
Output Capacitor, Recommended Specification
Symbol
Parameter
Conditions
Capacitance (Note 9)
I
OUT
= 150mA, V
IN
= 5.0V
ESR
Value
Min
C
OUT
Output Capacitance
1.0
0.7
0.003
Limit
(Note 8)
Max
47
0.300
µF
Ω
Units
Note 1:
Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Operating Ratings are conditions under which operation
of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. For guaranteed performance limits and associated test conditions,
see the Electrical Characteristics tables.
Note 2:
All voltages are with respect to the potential at the GND pin.
Note 3:
Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at T
J
= 160°C (typ.) and disengages at T
J
= 140°C (typ.).
Note 4:
The Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin. The machine model is a 200pF capacitor discharged
directly into each pin. (MIL-STD-883 3015.7)
Note 5:
In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may have to be
derated. Maximum ambient temperature (T
A-MAX
) is dependent on the maximum operating junction temperature (T
J-MAX-OP
= 125°C), the maximum power
dissipation of the device in the application (P
D-MAX
), and the junction-to ambient thermal resistance of the part/package in the application (θ
JA
), as given by the
following equation: T
A-MAX
= T
J-MAX-OP
– (θ
JA
× P
D-MAX
).
Note 6:
Junction-to-ambient thermal resistance is highly application and board-layout dependent. In applications where high maximum power dissipation exists,
special attention must be paid to thermal dissipation issues in board design.
Note 7:
Min and Max limits are guaranteed by design, test, or statistical analysis. Typical numbers are not guaranteed, but do represent the most likely norm.
Note 8:
Min and Max limits are guaranteed by design
Note 9:
The capacitor tolerance should be 30% or better over temperature. The full operating conditions for the application should be considered when selecting
a suitable capacitor to ensure that the minimum value of capacitance is always met. Recommended capacitor type is X7R. However, dependent on application,
X5R, Y5V, and Z5U can also be used. The shown minimum limit represents real minimum capacitance, including all tolerances and must be maintained over
temperature and dc bias voltage (See capacitor section in Applications Hints)
Note 10:
Dropout voltage is defined as the input to output voltage differential at which the output voltage falls to 100mV below the nominal output voltage. This
specification does not apply for output voltages below 1.8V.
