LP2954AISX National Semiconductor, LP2954AISX Datasheet - Page 4

• Manufacturer Part Number: LP2954AISX
• Description: 5V and Adjustable Micropower Low-Dropout Voltage Regulators
• Manufacturer: National Semiconductor

V
www.national.com
V
THR
Additional Specifications for the Adjustable Device (LP2954AIM and LP2954IM)
Dropout Detection Comparator
Shutdown Input
I
THR
Symbol
O
Limits in standard typeface are for T
are guaranteed by production testing or correlation techniques using standard Statistical Quality Control (SQC) methods. Un-
less otherwise noted: V
V
Electrical Characteristics
I
HYST
HYST
Note 1: Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the de-
vice outside of its rated operating conditions.
Note 2: The maximum allowable power dissipation is a function of the maximum junction temperature, T
and the ambient temperature, T
Exceeding the maximum allowable power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown. The junction-to-ambient
thermal resistance of the TO-220 (without heatsink) is 60˚C/W, 73˚C/W for the TO-263, and 160˚C/W for the SO-8. If the TO-263 package is used, the thermal re-
sistance can be reduced by increasing the P.C. board copper area thermally connected to the package: Using 0.5 square inches of copper area,
1 square inch of copper area,
If an external heatsink is used, the effective junction-to-ambient thermal resistance is the sum of the junction-to-case resistance (3˚C/W), the specified thermal re-
sistance of the heatsink selected, and the thermal resistance of the interface between the heatsink and the LP2954. Some typical values are listed for interface ma-
terials used with TO-220:
V
V
B
(SINK)
V
I
REF
V
V
GND
I
(MAX)
(FB)
REF
REF
OH
I
(MIN)
REF
OL
OS
B
/ T
/
Reference Voltage
Reference Voltage
Line Regulation
Reference Voltage
Temperature
Coefficient
Feedback Pin Bias
Current
Ground Pin Current
at Shutdown (Note
6)
Output OFF
Pulldown Current
Output HIGH
Leakage Current
Output LOW
Voltage
Upper Threshold
Voltage
Lower Threshold
Voltage
Hysteresis
Input Offset Voltage
Hysteresis
Input Bias Current
Parameter
IN
JA
A
= 6V, I
. The maximum allowable power dissipation at any ambient temperature is calculated using:
is 37˚C/W; and with 1.6 or more square inches of copper area,
L
= 1 mA, C
(Note 10)
V
VO(NOM)+1V
V
VO(NOM)+1V to 30V
(Note 11)
(Note 3)
V
(Note 12)
V
V
I
(Note 13)
(Note 13)
(Note 13)
(Referred to V
V
O
J
IN
IN
SHUTDOWN
OH
IN
IN
(COMP) = 400µA
= 25˚C, bold typeface applies over the −40˚C to +125˚C temperature range. Limits
= 2.5V to
= 2.5V to
= V
(S/D) = 0V to 5V
= 30V
Conditions
O
(NOM)−0.5V
(Continued)
L
= 2.2 µF.
1.1V
REF
)
Typical
1.230
0.03
0.01
−60
−85
4
105
150
20
20
15
±
10
6
3
1.215
1.205
−110
−160
−7.5
Min
−80
−95
−10
−30
−50
30
20
JA
2954AI
is 32˚C/W. The junction-to-case thermal resistance is 3˚C/W.
J
(MAX), the junction-to-ambient thermal resistance,
1.245
1.255
Max
140
250
400
−35
−25
−55
−40
0.1
0.2
7.5
40
60
10
30
50
1
2
1.205
1.190
−110
−160
−7.5
Min
−80
−95
−10
−30
−50
30
20
2954I
1.255
1.270
Max
140
250
400
−35
−25
−55
−40
0.2
0.4
7.5
40
60
10
30
50
1
2
JA
is 50˚C/W; with
ppm/˚C
Units
mA
mV
mV
mV
mV
mV
mV
nA
µA
µA
nA
V
J-A
,
.