The LP2950 and LP2951 are micropower voltage regulators ideally suited for use in battery-powered systems. These devices
feature very low quiescent current (typ.75µA), and very low dropout voltage (typ.45mV at light loads and 380mV at 100mA)
thus prolonging battery life. The quiescent current increases only slightly in dropout. The LP2950/LP2951 has positive
transient protection up to 60V and can survive unregulated input transient up to 20V below ground.
The LP2950 and LP2951 were designed to include a tight initial tolerance (typ. 0.5%), excellent load and line regulation (typ.
0.05%), and a very low output voltage temperature coefficient, making these devices useful as a low-power voltage reference.
The LP2950 is offered in the 3-pin TO-92 package. LP2951 is available in 8-pin plastic SOIC and DIP packages and offers
three major additional system features. An error flag output warns of a low output voltage, often due to failing batteries on
input. The LP2951 also features the logic-compatible shutdown input which enables the regulator to be switched on and off.
The LP2951 device may be pin-strapped for a 5V, 3.3V, or 3V output, or programmed from 1.24V to 29V with an external
pair of resistors.
ORDERING INFORMATION
PACKAGE TYPE
TO-92
8 LEAD PDIP 8 LEAD SOIC
LP2950ACN-X LP2951ACP-X LP2951ACS-X
LP2950CN-X
LP2951CP-X
LP2951CS-X
X = 3.3V, or 3V
OPERATING
TEMP. RANGE
IND.
IND
PIN CONNECTION
8L SOIC/ 8L PDIP
OUTPUT 1
SENSE 2
SHUTDOWN 3
GROUND 4
8 INPUT
7 FEEDBACK
6 V
TAP
5 ERROR
Top View
TO-92
OUTPUT
INPUT
GND
Bottom View
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
LP2950/LP2951
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Input Supply Voltage
SHUTDOWN Input Voltage,
Error Comparator Output
Voltage,(Note 9)
FEEDBACK Input Voltage
(Note 9) (Note 10)
Power Dissipation
Junction Temperature
Storage Temperature
Soldering Dwell Time, Temperature
-0.3 to +30V
Wave
Infrared
Vapor Phase
ESD
4 seconds, 260°C
4 seconds, 240°C
4 seconds, 219°C
TBD
-1.5 to +30V
OPERATING RATINGS
(Note 1)
Internally Limited
+150°C
-65°C to +150°C
Max. Input Supply Voltage
Junction Temperature Range
(T
J
) (Note 8)
LP2950AC-XX, LP2950C-XX
LP2951AC-XX, LP2951C-XX
30V
-40°C to +125°C
ELECTRICAL CHARACTERISTICS
at Vs=Vout+1V, Ta=25°C, unless otherwise noted
.
Parameter
3 V Versions
(Note 16)
Output Voltage
TJ = 25°C
-25°C
≤T
J
≤85°C
Full Operating Temperature Range
Output Voltage
3.3 V Versions
(Note 16)
Output Voltage
TJ = 25°C
-25°C
≤T
J
≤85°C
Full Operating Temperature Range
Output Voltage
5 V Versions
(Note 16)
Output Voltage
TJ = 25°C
-25°C
≤T
J
≤85°C
Full Operating Temperature Range
Output Voltage
All Voltage Options
Output Voltage
Temperature Coefficient
Line Regulation (Note 14)
Load Regulation (Note 14)
Dropout Voltage
(Note 5)
Ground Current
(Note 12) (Note 4)
6V
≤V
in
≤30V
(Note 15)
100
µA ≤I
L
≤
100 mA
IL = 100µ A
IL = 100 mA
IL = 100
µA
IL = 100 mA
Current Limit
Thermal Regulation
Vout = 0
(Note 13)
20
0.03
0.04
50
380
75
8
160
0.05
0.1
0.1
80
450
120
12
200
0.2
50
0.04
0.1
50
380
75
8
160
0.05
0.2
0.2
80
450
120
12
200
0.2
ppm/°C
%
%
mV
mV
µA
mA
mA
%/W
100
µA ≤I
L
≤100
mA
TJ
≤T
JMAX
(Note 3)
4.975
4.95
4.94
4.925
5.0
5.0
5.0
5.0
5.025
5.050
5.06
5.075
4.95
4.925
4.90
4.88
5.0
5.0
5.0
5.0
5.05
5.075
5.10
5.12
V
V
V
V
100
µA ≤I
L
≤100
mA
TJ
≤T
JMAX
(Note 3)
3.284
3.267
3.260
3.254
3.3
3.3
3.3
3.3
3.317
3.333
3.340
3.346
3.267
3.251
3.234
3.221
3.3
3.3
3.3
3.3
3.333
3.350
3.366
3.379
V
V
V
V
100
µA ≤I
L
≤100
mA
TJ
≤T
JMAX
(Note 3)
2.985
2.970
2.964
2.958
3.0
3.0
3.0
3.0
3.015
3.030
3.036
3.042
2.970
2.955
2.940
2.928
3.0
3.0
3.0
3.0
3.030
3.045
3.060
3.072
V
V
V
V
Conditions
(Note 2)
Min.
LP2950AC
LP2951AC
Typ.
Max.
Min.
LP2950C
LP2951C
Typ.
Max.
Units
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
LP2950/LP2951
ELECTRICAL CHARACTERISTICS
(Note 2) (Continued)
PARAMETER
Output Noise,
10Hz to 100KHz
CONDITIONS
(Note 2)
CL = 1µF
CL = 200
µF
CL = 13.3
µF
(Bypass = 0.01
µF
pins 7 to
1(LP2951))
Min.
LP2950AC
LP2951AC
Typ.
430
160
100
LP2951AC
1.22
1.235
1.25
1.27
40
20
60
1.21
1.185
Max.
Min.
LP2950C
LP2951C
Typ.
430
160
100
LP2951C
1.235
1.26
1.285
40
60
50
Max.
Units
µV
rms
µV
rms
µV
rms
8-Pin Versions only
Reference Voltage
Reference Voltage
Feedback Pin Bias Current
Reference Voltage Temperature
Coefficient
Feedback Pin Bias Current
Temperature Coefficient
Error Comparator
Output Leakage Current
Output Low Voltage
Upper Threshold Voltage
Lower Threshold Voltage
Hysteresis
Shutdown Input
Input logic Voltage
Shutdown Pin Input Current
(Note 3)
Regulator Output Current in
Shutdown (Note 3)
V
OH
V
V
nA
ppm/°C
Over Temperature (Note 7)
1.19
( Note 12 )
0.1
0.1
nA/°C
= 30V
0.01
150
40
60
75
15
1
250
40
95
0.01
150
60
75
15
1
250
µA
mV
mV
Vin = 4.5V
IOL = 400µA
(Note 6)
(Note 6)
(Note 6)
Low (Regulator ON)
High (Regulator OFF)
Vs = 2.4V
Vs = 30V
(Note 11)
95
mV
mV
1.3
2
30
450
3
0.7
2
50
600
10
1.3
30
450
3
0.7
50
600
10
V
V
µA
µA
µA
Note 1:
Absolute Maximum Ratings are limits beyond which damage to the device 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:
Unless otherwise specified all limits guaranteed for V
IN
= ( V
ONOM
+1)V, I
L
= 100
µA
and C
L
= 1
µF
for 5V versions and 2.2µF for 3V and 3.3V versions.
Limits appearing in
boldface
type apply over the entire junction temperature range for operation. Limits appearing in normal type apply for T
A
= T
J
= 25°C
Additional conditions for the 8-pin versions are FEEDBACK tied to V
TAP
, OUTPUT tied to SENSE and V
SHUTDOWN
≤
0.8V.
Note 3:
Guaranteed and 100% production tested.
Note 4:
Guaranteed but not 100% production tested. These limits are not used to calculate outgoing AQL levels.
Note 5:
Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below its nominal value measured at 1V differential.
At very low values of programmed output voltage, the minimum input supply voltage of 2V ( 2.3V over temperature) must be taken into account.
Note 6:
Comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below the nominal reference voltage measured at
V
IN
= ( V
ONOM
+1)V. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = Vout/Vref = (R1 + R2)/R2. For example,
at a programmed output voltage of 5V, the error output is guaranteed to go low when the output drops by 95 mV x 5V/1.235 = 384 mV. Thresholds remain constant
as a percent of V
out
as V
out
is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed.
Note 7:
V
ref
≤V
out
≤
(V
in
- 1V), 2.3
≤V
in
≤30V,
100µA≤I
L
≤
100 mA, T
J
≤
T
JMAX
.
Note 8:
The junction-to-ambient thermal resistance are as follows:180°C/W and 160°C/W for the TO-92 (N) package with 0.40 inch and 0.25 inch leads to the
printed circuit board (PCB) respectively, 105°C/W for the molded plastic DIP (P) and 160°C/W for the molded plastic SO-8 (S). The above thermal resistances for
the N, S and P packages apply when the package is soldered directly to the PCB.
Note 9:
May exceed input supply voltage.
Note 10:
When used in dual-supply systems where the output terminal sees loads returned to a negative supply, the output voltage should be diode-clamped to
ground.
Note 11:
V
shutdown
≥
2V, V
in
≤
30V, V
out
=0, Feedback pin tied to 5V
TAP
.
Note 12:
Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range.
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
LP2950/LP2951
Note 13:
Thermal regulation is defined as the change in output voltage at a time T after a change in power dissipation is applied, excluding load or line regulation
effects. Specifications are for a 50mA load pulse at V
IN
=30V (1.25W pulse) for T =10 ms.
Note 14:
Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are
covered under the specification for thermal regulation.
Note 15:
Line regulation for the LP2951 is tested at 150°C for I
L
= 1 mA. For I
L
= 100
µA
and T
J
= 125°C, line regulation is guaranteed by design to 0.2%. See
typical performance characteristics for line regulation versus temperature and load current.
Note 16:
All LP2950 devices have the nominal output voltage coded as the last two digits of the part number. In the LP2951 products, the 3.0V and 3.3V versions
are designated by the last two digits, but the 5V version is denoted with no code of the part number.
BLOCK DIAGRAM AND TYPICAL APPLICATIONS
LP2950-XX
LP2951-XX
V
OUT
I
L
≤
100mA
8
INPUT
1
OUTPUT
2
+
FROM
CMOS
OR TTL
3
SHUT-
DOWN
+
50mV
+
-
ERROR
4
GROUND
-
ERROR
AMPLIFIER
SENSE
6
V
TAP
5
TO CMOS
OR TTL
+
330kΩ
SEE APPLICATION
HINTS
UNREGULATED DC
UNREGULATED DC
+
+
INPUT
OUTPUT
+
-
ERROR
AMPLIFIER
+
SEE APPLICATION
HINTS
V
OUT
I
L
≤
100mA
7
FEED-
BACK
+
1.23V
REFERENCE
+
1.23V
REFERENCE
GROUND
ERROR DETECTION COMPARATOR
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
LP2950/LP2951
TYPICAL PERFORMANCE CHARACTERISTICS
Quiescent Current
10
GROUND CURRENT (mA)
OUTPUT VOLTAGE (V)
6
Dropout Characteristics
5V OUTPUT
Input Current
250
225
INPUT CURRENT (µA)
200
175
150
125
100
75
50
25
0
R
L
=
∞
5V OUTPUT
R
L
= 50 kΩ
5
4
3
R
L
= 50Ω
R
L
= 50 kΩ
1
0.1
2
1
0
1
2
3
4
5
INPUT VOLTAGE (V)
6
0.01
0.1
1
10
LOAD CURRENT (mA)
100
0
0
1
2 3 4 5 6 7 8
INPUT VOLTAGE (V)
9 10
Input Current
120
110
100
90
80
70
60
50
40
30
20
10
0
5.06
5V OUTPUT
Temperature Drift of 3
Representative Units
160
5V OUTPUT
Quiescent Current
140
120
100
80
I
L
= 0
I
L
= 1 mA
5V OUTPUT
OUTPUT VOLTAGE (V)
INPUT CURRENT (mA)
R
L
= 50Ω
5.04
5.02
5.0
4.98
4.96
0.2%
QUIESCENT CURRENT (µA)
60
40
20
0
0
1
2 3 4 5 6 7
INPUT VOLTAGE (V)
8
0
1
2 3 4 5 6 7 8
INPUT VOLTAGE (V)
9 10
4.94
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (° C)
Quiescent Current
120
QUIESCENT CURRENT (µA)
110
100
90
80
70
60
50
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (° C)
I
L
= 100µA
V
IN
= 6V
Quiescent Current
10
QUIESCENT CURRENT (mA)
8
QUIESCENT CURRENT (µA)
5V OUTPUT
Quiescent Current
5V OUTPUT
5V OUTPUT
7
6
5
4
3
2
1
0
0
1
2 3 4 5
6 7
INPUT VOLTAGE (V)
8
I
L
= 100mA
9
V
IN
= 6V
I
L
= 100mA
8
7
-75 -50 -25 0 25 50 75 100 125 150
TEMPERATURE (° C)
Advanced Monolithic Systems, Inc.
6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140