®
SPX2954
250mA Low Dropout Voltage Regulator
FEATURES
■
5.0V and 3.3V Versions at 250mA
Output
■
Accurate 0.5% for SPX2954A
■
Very Low Quiescent Current
■
Low Dropout: 310mV at 250mA
■
Extremely Tight Load and Line Regulation
■
Very Low Temperature Coefficient
■
Current and Thermal Limiting
■
Need only 1µF for Stability
■
Direct Replacement for LP2954
■
Offered in TO-92, TO-263, SOT-223, &
TO-220; also SOIC--8
Pin Versions Only
■
Error Flag Warns of Output Dropout
■
Logic-Controlled Electronic Shutdown
■
Programmable Output from 1.24V to 30V
+V
IN
100K
ERROR
OUTPUT
5
8
______
ERROR
+V
IN
V
OUT
1
1.2 to 30V
SPX2954
SHUTDOWN
INPUT
3
SD
GND
4
R
1
FB
7
+
3.3µF
.01µF
1.23V
V
REF
R
2
DESCRIPTION
The SPX2954 and SPX2954A are low power voltage regulators. These devices are an excellent
choice for use in battery-powered applications such as cordless telephones, radio control
systems, and portable computers. The SPX2954 and SPX2954A feature low quiescent current
and low dropout voltage (typ. 20mV at 100µA and 310mV at 250mA). This includes a tight initial
tolerance (0.5% for SPX2954A), extremely good load and line regulation (0.05% typ.), and very
low output temperature coefficient (20 ppm/°C typ.), making the SPX2954/SPX2954A useful as
a low-power voltage reference.
The error flag output feature is used as a power-on reset for warning of a low output voltage, due
to a falling input voltage. The logic-compatible shutdown feature enables the regulator to be
switched ON and OFF. The SPX2954/SPX2954A is offered in 3-pin TO-92, TO-263, SOT-223
and TO-220 packages, and 8 pin SOIC package.
Note:: Tab is internally connected to GND on T0-263, SOT-223, and TO-220-3.
TO-263-3 Package (T)
TO-263-5 Package (T5)
8-Pin Surface Mount (S)
1
2
SPX2954
8
7
6
5
INPUT
FEEDBACK
5V, 3.3V TAP
OUTPUT
TO-92 (N)
1
2
3
SOT-223 Package (M3)
TO-220-3 Package (U) TO-220-5 Package (U5)
OUTPUT
SPX2954
1
2
3
1
SPX2954
SENSE
SPX2954
1
INPUT
GND
2
3
SHUTDOWN
1) INPUT
3
2 3 4 5
2) OUTPUT
GND
3) GND
4
4) SHUTDOWN
5) ERROR
Top View
SPX2954
SPX2954
1) INPUT
2) OUTPUT
ERROR
Bottom View
V
IN
GND
V
OUT
Front View
1 2 3
V
IN
GND V
OUT
1 2 3 4 5
3) GND
4) SHUTDOWN
5) ERROR
V
IN
GND
V
OUT
Top View
Top View
Front View
Front View
Pin Connections
Date: 12/9/05
SPX2954, 250mA Low Dropout Voltage Regulator
© Copyright 2005 Sipex Corporation
1
ABSOLUTE MAXIMUM RATINGS
Power Dissipation........................................Internally Limited
Lead Temperature (soldering, 5 seconds) ................260°C
Storage Temperature Range........................-65°C to +150°C
Operating Junction Temperature Range......-40°C to +125°C
Input Supply Voltage...........................................-0.3V to +30V
Feedback Input Voltage....................................-1.5V to +30V
Shutdown Input Voltage .................................-0.3V to +30V
Error Comparator Output...................................-0.3V to +30V
ESD Rating................................................................2kV Min
ELECTRICAL CHARACTERISTICS
PARAMETER
3.3 V Versions
Output Voltage
CONDITIONS
V
IN
=V
O
+ 1V, I
L
=100µA, C
L
=1µF (
NOTE
2), T
A
= 25°C, unless otherwise specified.
SPX2954A
MIN.
3.284
3.267
3.260
3.251
TYP.
3.3
3.3
3.3
3.3
MAX
3.317
3.333
3.340
3.350
SPX2954
MIN. TYP. MAX.
3.267
3.251
3.234
3.201
3.3
3.3
3.3
3.3
3.333
3.350
3.366
3.399
UNIT
V
T
J
=25°C
-25°C≤T
J
≤85°C
Full Operating Temp.
100µA
≤I
L
≤250
mA
T
J
≤T
JMAX
T
J
= 25°C
-25°C
≤T
J
≤85°C
Full Operating Temp.
100µA
≤I
L
≤250
mA
T
J
≤T
JMAX
(N
OTE
1)
Output Voltage
5 V Versions
Output Voltage
V
4.975
4.950
4.940
4.925
5.0
5.0
5.0
5.0
5.025
5.050
5.060
5.075
4.950
4.925
4.900
4.850
5.0
5.0
5.0
5.0
5.050
5.075
5.100
5.150
V
Output Voltage
All Voltage Options
Output Voltage
Temperature Coefficient
V
20
0.03
0.04
60
290
310
150
3
10
270
0.05
430
160
100
100
0.10
0.20
100
450
500
170
6
14
550
0.2
50
0.04
0.10
60
290
310
150
3
10
270
0.05
430
160
100
150
0.20
0.30
100
450
500
170
6
14
550
0.2
ppm/°C
%
%
mV
Line Regulation (N
OTE
3) V
O
+1V≤V
IN
≤30V
|
(N
OTE
4)
Load Regulation (N
OTE
3) 100
µA≤I
L
≤250
mA
Dropout Voltage
(N
OTE
5)
Ground Current
I
L
= 1mA
I
L
= 100 mA
I
L
= 250 mA
I
L
= 1mA
I
L
= 100 mA
I
L
= 250 mA
V
OUT
= 0
C
L
= 1µF
C
L
= 200
µF
C
L
= 3.3
µF,
Bypass=
0.01µF from Pin 7 to
Pin 1 (8 pin Versions)
8-Pin Versions only
Reference Voltage
Reference Voltage
Feedback Pin
Bias Current
Vref Temperature
Coefficient
Feedback I
BIAS
Temperature Coefficient
Over Temp (N
OTE
6)
1.220
1.190
µA
mA
mA
mA
%/W
µV
rms
µV
rms
µV
rms
Current Limit
Thermal Regulation
Output Noise,
10Hz to 100kHz
1.235
40
20
0.1
1.250
1.270
60
1.210 1.235 1.260
1.185
40
50
0.1
1.285
60
V
V
nA
ppm/°C
nA/°C
Date: 12/9/05
SPX2954, 250mA Low Dropout Voltage Regulator
© Copyright 2005 Sipex Corporation
2
ELECTRICAL CHARACTERISTICS (Cont.)
PARAMETER
Error Comparator
Output Leakage Current
Output Low Voltage
Upper Threshold Voltage
Lower Threshold Voltage
Hysteresis
Shutdown
Input logic Voltage
Shutdown Input Current
Low (Regulator ON)
High (Regulator OFF)
VS = 2.4V
VS= 30V
V
OH
= 30V
V
IN
= V
O
-0.5V,
I
OL
= 400µA
(N
OTE
7)
(N
OTE
7)
(N
OTE
7)
CONDITIONS
V
IN
=V
O
+1V, I
L
=100µA, C
L
=1µF (
NOTE
2), T
A
= 25°C, unless otherwise specified.
SPX2954A
MIN. TYP.
0.01
150
40
60
75
15
1.3
2.0
30
400
3
50
800
10
0.7
2.0
95
MAX
1
250
40
SPX2954
MIN. TYP. MAX.
0.01
150
60
75
15
1.3
30
400
3
0.7
50
800
10
95
1
250
UNIT
µA
mV
mV
mV
mV
V
µA
µA
Regulator Output Current (N
OTE
8)
in Shutdown
Thermal Resistance
Θ
JA
TO-263-3
SOIC-8
TO-92-3
SOT-223
TO-220-3
31.4
128.4
131.9
62.3
29.4
°C/W
°C/W
°C/W
°C/W
°C/W
N
OTE
1: Output or reference voltage temperature coefficients defined as the worst case voltage change divided
by the total temperature range.
N
OTE
2: Unless otherwise specified all limits guaranteed for T
J
= 25°C, V
IN
= 6V, I
L
= 100µA and C
L
= 1µF.
Additional conditions for the 8-pin versions are feedback tied to 5V tap and output tied to output sense
(V
OUT
= 5V) and V
SHUTDOWN
≤
0.8V.
N
OTE
3: 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.
N
OTE
4: Line regulation for the SPX2954 is tested at I
L
= 1mA.
N
OTE
5: Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV
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.
N
OTE
6: V
REF
≤V
OUT
≤
(V
IN
- 1V), 2.3
≤V
IN
≤30V,
100µA≤I
L
≤
250mA, T
J
≤
T
JMAX
.
N
OTE
7: Comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below
the nominal reference voltage measured at 6V input. To express these thresholds in terms of output
voltage change, multiply by the error amplifier gain = V
OUT
/V
REF
= (R
1
+ R
2
)/R
2
. 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.
N
OTE
8: V
SHUTDOWN
≥
2V, V
IN
≤
30V, V
OUT
=0, Feedback pin tied to 5V/3.3V Tap.
Date: 12/9/05
SPX2954, 250mA Low Dropout Voltage Regulator
© Copyright 2005 Sipex Corporation
3
UNREGULATED DC
5V
7
FEEDBACK
+
8
INPUT
1
OUTPUT
2
SENSE
+
_
FROM
CMOS OR
TTL
180kΩ
6
ERROR
AMPLIFIER
5V TAP
3
SHUTDOWN
60 mV
330kΩ
+
60kΩ
+
5
______
ERROR
+
_
ERROR DETECTION
COMPARATOR
1µF
.
.
TO CMOS OR
TTL
+
1.23V
4
REFERENCE
GROUND
SPX2954 Block Diagram, 8 Lead 5V Version
TYPICAL PERFORMANCE CHARACTERISTICS
1.8
SHUTDOWN THRESHOLD VOLTAGE (V)
OUTPUT VOLTAGE
CHANGE (mV)
5
VOLTAGE NOISE
SPECTRAL DENSITY (µV/Hz)
3.5
3.0
I
L
= 100mA
C
L
= 1µF
1.6
1.4
1.2
1.0
0.8
0.6
-75 -50 -25
0
25
50
75 100 125 150
TEMPERATURE (ºC)
4
2
0
-2
2.5
C
L
= 220µF
2.0
1.5
1.0
0.5
0.0
C
L
= 3.3µF
C
BYP
= 0.1µF
POWER
DISSIPATION (W)
~
~
1
1.25W
0
-1
0
10
20
30
40
50
TIME (µs)
10
2
10
3
10
4
10
5
FREQUENCY (Hz), C
BYP
=0.1uF
Shutdown Threshold Voltage
Thermal Response
Output Noise
30
OUTPUT VOLTAGE CHANGE (mV)
80
= 50µA
I
L
=50mA
I
L
= 100µA
RIPPLE REJECTION (dB)
25
20
15
10
5
0
~
~
10
5
0
-5
-10
5
10
15
20
T
J
= 125 ºC
T
J
= 150 ºC
70
60
50
40
30
20
10
C
L
= 1µF
V
IN
= 6V
V
OUT
= 5V
I
L
= 100mA
I
L
= 1mA
I
L
= 100µA
25
30
10
1
10
2
10
3
10
4
10
5
10
6
INPUT VOLTAGE (V)
FREQUENCY (Hz)
Line Regulation
Date: 12/9/05
Ripple Rejection
SPX2954, 250mA Low Dropout Voltage Regulator
© Copyright 2005 Sipex Corporation
4
TYPICAL PERFORMANCE CHARACTERISTICS
6
5
OUTPUT VOLTAGE (VOLTS)
INPUT CURRENT (µA)
250
225
R
L
= 50kΩ
10
4
R
L
=50kΩ
175
150
125
100
75
50
25
0
GROUND PIN CURRENT (mA)
200
1
3
R
L
=50kΩ
2
1
0
0
1
2
3
4
5
6
INPUT VOLTAGE (VOLTS)
R
L
=
8
0.1
0
1
2
3
4
5
6
7
8
9 10
0.01
0.1
1
10
100
INPUT VOLTAGE (VOLTS)
LOAD CURRENT (mA)
Dropout Characteristics
Input Current
Quiescent Current
320
280
GROUND CURRENT (µA)
INPUT CURRENT (mA)
240
200
160
I
L
= 0
I
L
= 1mA
120
80
40
0
0
1
2
3
4
5
6
7
8
160
150
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
0
1
2
3
4
5
6
6
GROUND CURRENT (mA)
R
L
=50
Ω
V
OUT
= 5V
5
V
IN
= 6V
I
L
= 100mA
4
3
7
8
9 10
-75 -50 -25
0
25 50
75 100 125 150
TEMPERATURE (ºC)
INPUT VOLTAGE (VOLTS)
INPUT VOLTAGE (VOLTS)
Ground Current
8
7
Input Current
190
Ground Current
QUIESCENT CURRENT (µA)
GROUND CURRENT (mA)
6
I
L
=100mA
170
V
IN
=6V
I
L
=100uA
5
4
3
2
1
0
0
1
2
3
4
5
6
7
8
150
130
-75 -50 -25
0
25 50
75 100 125 150
INPUT VOLTAGE
TEMPERATURE (ºC)
Ground Current
Quiescent Current
Date: 12/9/05
SPX2954, 250mA Low Dropout Voltage Regulator
© Copyright 2005 Sipex Corporation
5
