®
SPX2808
300mA Low Dropout Voltage Regulator
FEATURES
■
3.3V and 3.5V Versions
■
Input-Output Differential is 0.35V at 200mA
■
Input-Output Differential is 0.45V at 300mA
■
Mirror-Image Insertion Protection
■
Internal Thermal Protection
■
Available in SOT-223 and SOT-89
Packages
■
Short Circuit Protection
■
2% Output Accurancy, SPX2808A
APPLICATIONS
■
CD-ROMs
■
Scanners
■
Radio Control Systems
■
■
■
■
SOT-89 (M1)
SOT-223 (M3)
1
2
3
1
2
3
V
IN
GND V
OUT
V
IN
GND V
OUT
Top View
Now Available in Lead Free Packaging
Portable Instrumentation
Cordless Telephones
USBs
Toys
DESCRIPTION
The SPX2808 is a low power, positive voltage regulator. This device is an excellent choice for
use in battery-powered applications such as cordless telephones, radio control systems, and
portable computers. The SPX2808 features offers very low quiescent currents (0.4mA), and very
low drop output voltage (50mV at light load and 450mV at 300mA). The SPX2808 is offered in
a 3-pin SOT-223 and SOT-89 package.
TYPICAL APPLICATIONS CIRCUIT
V
IN
V
OUT
SPX2808
100µF,
1µF
C
1
Gnd
ESR 0.05 to 0.6
ohms
Date: 5/25/04
SPX2808 300mA Low Dropout Voltage Regulator
© Copyright 2004 Sipex Corporation
1
ABSOLUTE MAXIMUM RATINGS
Power Dissipation (note 3) ........................................ Internally limited
Lead Temp (soldering, 5 seconds) ............................................ 260°C
Storage Temperature Range ..................................... -65°C to +150°C
Input Supply Voltage Range .......................................... -0.3V to +30V
ESD Rating (note 4) ...................................................................... 2kV
RECOMMENDED OPERATING CONSITIONS
Input Supply Voltage Range ............................................. 3.0V to 26V
Operating Junction Temperature Range ....................... -40°C to 85°C
SOT-89
Θ
JA
............................................................................. 90°C/W
SOT-223 ................................................................................. 60°C/W
ELECTRICAL CHARACTERISTICS
at T
A
=25°C, unless otherwise specified. (Note 1)
PARAMETER
3.3V Version
Quiescent Current (I
Q
)
Output Voltage (V
OUT
)
Line Regulation
Load Regulation
Dropout Voltage (V
DROP
)
I
OUT
= 0mA, Except I
CONT
I
OUT
= 50mA, Except I
CONT
V
IN
= 8V, at Output Off
I
OUT
= 40mA,
5
≤
V
IN
≤
10V
I
OUT
= 1mA
→
60mA
I
OUT
= 1mA
→
100mA
I
OUT
= 60mA
I
OUT
= 200mA
I
OUT
= 300mA
I
OUT
when V
OUT
drops 0.3V
from V
O
(typ)(Note 3)
5 ms pulse, 12.5% duty cycle
I
OUT
= 0mA, Except I
CONT
I
OUT
= 50mA, Except I
CONT
V
IN
= 8V, at Output Off
I
OUT
= 40mA,
5
≤
V
IN
≤
10V
I
OUT
= 1mA
→
60mA
I
OUT
= 1mA
→
100mA
I
OUT
= 60mA
I
OUT
= 200mA
I
OUT
= 300mA
I
OUT
when V
OUT
drops 0.3V
from V
O
(typ)(Note 3)
5 ms pulse, 12.5% duty cycle
3.43
100
3.5
0.3
10
30
0.2
0.35
0.45
400
100
300
3.24
CONDITIONS
Min
Typ
SP2808A
100
3.3
0.3
10
30
0.2
0.35
0.45
400
100
300
200
3.57
0.4
40
80
0.3
0.7
3.40
100
3.5
0.3
10
30
0.2
0.35
0.45
400
100
300
200
3.36
0.4
40
80
0.3
0.7
3.20
Max
Min
Typ
SP2808
100
3.3
0.3
10
30
0.2
0.35
0.45
400
100
300
200
3.60
0.4
40
80
0.3
0.7
200
3.40
0.4
40
80
0.3
0.7
µA
V
%/V
mV
mV
V
V
V
mA
ppm/°C
mA
µA
V
%/V
mV
mV
V
V
V
mA
ppm/°C
mA
Max
Units
Continuous Output
Current (I
OUT
)
Temperature Coefficient
Pulse Output Current
3.5V Version
Quiescent Current (I
Q
)
Output Voltage (V
OUT
)
Line Regulation
Load Regulation
Dropout Voltage (V
DROP
)
Continuous Output
Current (I
OUT
)
Temperature Coefficient
Pulse Output Current
NOTES:
Note 1: When mounted as recommended. Derate 11mW/°C for SOT-89 packages when ambient temperatures are over 25°C.
Note 2: See TYPICAL APPLICATIONS notes to ensure constant junction temperature, low duty cycle pulse testing used.
Note 3: All limits are at 25°C; Boldface limits are over the full operating junction temperature range of -40°C to +85°C.
Note 4: The maximum power dissipation is a function of maximum junction temperature, total thermal resistance, and ambient temperature.
Note 5: Human body model, 100pF discharged through 1.5kΩ.
Date: 5/25/04
SPX2808 300mA Low Dropout Voltage Regulator
© Copyright 2004 Sipex Corporation
2
TYPICAL PERFORMANCE CHARACTERISTICS
800
2.0
500
OUTPUT CURRENT (mA)
T
J
= 25ºC
1.6
POWER DISSIPATION (W)
400
300
200
100
0
0
10
T
J
= 85ºC
T
J
= -40ºC
1.2
0.8
0.4
0.0
20
30
0 10 20 30 40 50 60 70 80 90
AMBIENT TEMPERATURE (ºC)
INPUT VOLTAGE (V)
Figure 1. Peak Output Current
Figure 2. Minimum Power Dissipation (SOT-89)
APPLICATION INFORMATION
The SPX2808 requires an output capacitor for
device stability. The value required varies greatly
depending upon the application circuit and other
factors. The high frequency characteristics of
electrolytic capacitors depend greatly on the
type and also on the manufacturer. Sometimes
only bench testing is the only means to deter-
mine the proper capacitor type and value. The
high quality 100µF aluminum electrolytic cov-
ers all general application circuits, this stability
can be obtained with a tantalum electrolytic
value of 47µF.
Another critical point of electrolytic character-
istics is its performance over temperature. The
SPX2808 is designed to operate starting at -
40°C which may not be true in the case of
electrolytic. Higher temperatures generally no
problem. The electrolytic. type in aluminum
will freeze around -30°C. This could cause an
oscillation at output of regulator. At a lower
temperature requirement by many applications
the capacitor should maintain its performance.
So as a result, for an application which regulator
junction temperature does not exceed 25°C, the
output capacitor can be reduced by the factor of
two over the value needed for the entire tem-
perature range.
In most applications the SPX2808 is operating
at few milliamps. In these applications the out-
put capacitance can be further reduced. For
example, when the regulator is running at 10mA
output current the output capacitance value is
half compared to the same regulator that is
running at 100mA. The value decreases with
higher output voltages, since the internal loop
gain is reduced.
The worst case occurs at the lower temperature
and maximum operating currents, the entire
circuit and the electrolytic, should be cooled
down to the minimum temperature. The mini-
mum of 0.6 volts required at the input of regula-
tor above the output to keep the power dissipa-
tion and die heating to its minimum. After the
value for the capacitor has been determined for
actual use, the value should be doubled.
Date: 5/25/04
SPX2808 300mA Low Dropout Voltage Regulator
© Copyright 2004 Sipex Corporation
3
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