Datasheet SPX2810AM3, SPX2810AM3-1.5, SPX2810AM3-2.5, SPX2810AM3-3.0, SPX2810AM3-3.3 Datasheet (Sipex Corporation)

Rev. 10/30/00

SPX2810

1A Low Dropout Voltage Regulator

Adjustable & Fixed Output,

Fast Response

FEATURES

APPLICATIONS

•

Adjustable Output Down To 1.2V

•

Portable Palmtop/Notebook Computer

•

Fixed Output Voltages 1.5V, 2.5V, 3.0V, 3.3V, 5.0V

•

SMPS Post-Regulator

•

Output Current Of 1A

•

Disk Drives

•

Low Dropout Voltage 1.2V Typ.

•

Portable Consumer Equipment

•

Extremely Tight Load And Line Regulation

•

Portable Instrumentation

•

Current & Thermal Limiting

•

Battery charger

•

Standard 3-Terminal Low Cost TO-220, TO-263, TO-252 & SOT-223

PRODUCT DESCRIPTION

The SPX2810 is a low power positive voltage regulator designed to source 1A output current. This device is an excellent choice for
use in battery-powered applications and portable computers. The SPX2810 features very low quiescent current and very low dropout
voltage of 1.2V at a full load and lower as output current decreases. This product is available as adjustable or fixed 1.5V, 2.5V, 3.0V,

3.3V, and 5V output voltages.

The SPX2810 is offered in a 3-pin surface mount packages SOT-223, TO-220, TO-252 & DD package. The output capacitor of 10µF
or larger is needed for the output stability of SPX2810 as required by most other regulator circuits

PIN CONNECTIONS

Front View

TO-220-3 (U)

SPX2810

1

23

ADJ/GND

V

OUT

V

IN

Top View

TO-263-3 (T)

1

SPX2810

2

3

ADJ/GND

V

OUT

V

IN

Front View

TO-252 (R)

ADJ/GND VINV

OUT

3

2

1

SPX2810

Top View

SOT-223 (M3)

ADJ/ GND

V

OUT

V

IN

SPX2810

132

Rev. 10/30/00

SPX2810

ABSOLUTE MAXIMUM RATINGS

Lead Temp. (Soldering, 10 Seconds) ..............................300°C Input Voltage........................................................ 10V

Storage Temperature Range ............................ -65° to +150°C Input to Output Voltage Differential .................... 10V

Operating Junction Temperature Range ......................

SPX2810 Control Section.......................... -45°C +125°C

SPX2810 Power Transistor.........................-45°C +150°C

ELECTRICAL CHARACTERISTICS

(NOTE 1) at I

OUT

= 10mA, TA=25°C, unless otherwise specified.

PARAMETER CONDITIONS Typ SPX2810A SPX2810 UNITS

Min Max Min Max

1.5V Version

1.485 1.515 1.470 1.530 Output Voltage (Note 2) SPX2810-1.5V, 0 < I

OUT

< 1A, 3.3V<VIN<10V 1.5

1.47 1.53 1.455 1.545

V

2.5V Version

2.475 2.525 2.450 2.550 Output Voltage (Note 2) SPX2810-2.5V, 0 < I

OUT

< 1A, 4.0V<VIN<10V 2.5

2.45 2.55 2.425 2.575

V

2.85V Version

2.822 2.879 2.793 2.907 Output Voltage (Note 2)

SPX2810-2.85V, 0 ≤ I

OUT

≤ 1A,

4.5V≤V

IN

≤

10V

2.85

2.793 2.907 2.650 2.936

V

3.0V Version

2.970 3.030 2.94 3.06 Output Voltage (Note 2)

SPX2810-3.0V, 0 ≤ I

OUT

≤ 1A, 4.5V≤V

IN

≤

10V

3

2.940 3.060 2.79 3.09

V

3.3V Version

3.267 3.333 3.234 3.366 Output Voltage (Note 2)

SPX2810-3.3V, 0 ≤ I

OUT

≤ 1A, 4.8V≤V

IN

≤

10V

3.3

3.234 3.366 3.069 3.399

V

5.0V Version

4.950 5.050 4.9 5.1 Output Voltage (Note 2)

SPX2810-5.0V, 0 ≤ I

OUT

≤ 1A, 6.5V≤V

IN

≤

12V

5

4.900 5.100 4.65 5.15

V

All Voltage Options

1.250 Reference Voltage (V

REF

)

V

IN

≤

7V, P≤ Pmax

1.5V≤ (V

IN

-V

OUT

)≤5.75V, 10mA≤I

OUT

≤

1A

1.225

1.263

1.270

1.225

1.225

1.212

1.270

1.288

V

Min. Load Current (Note 3)

1.5V≤ (V

IN

–V

OUT

)≤5.75V

5 10 10

mA

Line Regulation (∆V

REF(Vin

)) 2.75V≤VIN ≤7V, I

OUT

=10mA, TJ=25ºC (Note 3)

0.005 0.2 0.2

V

IN

≤

7V, I

OUT

=0mA, TJ=25ºC (Note 2)

0.005 0.2 0.2

%

10mA≤I

OUT

≤1A, (VIN-V

OUT

)=3V, TJ=25ºC

(Note 3)

0.05 0.3 0.3

Load Regulation(∆V

REF(IOUT

))

0≤I

OUT

≤1A, VIN=7V, TJ=25ºC (Note 2)

0.05 0.3 0.3

%

Dropout Voltage

∆

V

REF

=1% I

OUT

= 1A (Note 3)

I

OUT

≤ 1A (Note 2)

1.1 1.2 1.2

VIN=7V Current Limit

I

OUT

(MAX)

1.4V ≤ (V

IN

- V

OUT

) (Note3)

2 1.2 1.2 A

Rev. 10/30/00

SPX2810

ELECTRICAL CHARACTERISTICS (Cont.)

Long Term Stability T

A

=125ºC, 1000 Hrs. 0.3

(Note 2)

1 1 %

Thermal Regulation (∆V

OUT

(Pwr))

T

A

=25ºC, 20 ms pulse 0.01 0.020 0.020 %/W

Temperature Stability (∆V

OUT

(T))

0.25 %

Output Noise, RMS 10Hz to 10kHz TA=25ºC 0.003 % Vo

3.0 3.0 TO-220 Junction to Tab

Junction to Ambient

60 60

3.0 3.0 DD Package Junction to Tab

Junction to Ambient

60 60

15 15

Thermal Resistance

SOT-223 Package Junction to Tab
Junction to Ambient

156 156

The Bold specifications apply to the full operating temperature range.
Note 1: Changes in output voltage due to heating effects are covered under the specification for thermal regulation.
Note 2: Fixed Version Only
Note 3: Adjustable Version Only

ºC/W

Rev. 10/30/00

SPX2810

APPLICATION HINTS

The SPX2810 incorporates protection against over-current
faults, reversed load insertion, over temperature operation, and
positive and negative transient voltage. However, the use of
an output capacitor is required in order to improve the stability
and the performances.

Stability

The output capacitor is part of the regulator’s frequency
compensation system. Either a 22µF aluminum electrolytic
capacitor or a 10µF solid tantalum capacitor between the
output terminal and ground guarantees stable operation for all
operating conditions.
However, in order to minimize overshoot and undershoot, and
therefore optimize the design, please refer to the section
‘Ripple Rejection’.

Ripple Rejection

Ripple rejection can be improved by adding a capacitor
between the ADJ pin and ground as shown in figure 6. When
ADJ pin bypassing is used, the value of the output capacitor
required increases to its maximum (22µF for an aluminum
electrolytic capacitor, or 10µF for a solid tantalum capacitor).
If the ADJ pin is not bypass, the value of the output capacitor
can be lowered to 10µF for an electrolytic aluminum capacitor
or 4.7µF for a solid tantalum capacitor.
However the value of the ADJ-bypass capacitor should be
chosen with respect to the following equation:
C = 1 / ( 6.28 * F

R

* R1 )

Where C = value of the capacitor in Farads (select an
equal or larger standard value),
F

R

= ripple frequency in Hz,

R

1

= value of resistor R1 in Ohms.

If an ADJ-bypass capacitor is use, the amplitude of the output
ripple will be independent of the output voltage. If an ADJ­bypass capacitor is not used, the output ripple will be
proportional to the ratio of the output voltage to the reference
voltage:
M = V

OUT

/ V

REF

Where M = multiplier for the ripple seen when the ADJ pin
is optimally bypassed.
V

REF

= Reference Voltage

Reducing parasitic resistance and inductance

One solution to minimize parasitic resistance and inductance is
to connect in parallel capacitors. This arrangement will
improve the transient response of the power supply if your
system requires rapidly changing current load condition.

Thermal Consideration

Although the SPX2810 offers some limiting circuitry for
overload conditions, it is necessary not to exceed the
maximum junction temperature, and therefore to be careful
about thermal resistance. The heat flow will follow the lowest
resistance path, which is the Junction-to-case thermal
resistance. In order to insure the best thermal flow of the
component, a proper mounting is required. Note that the case
of the device is electrically connected to the output. In case
the case has to be electrically isolated, a thermally conductive
spacer can be used. However do not forget to consider its
contribution to thermal resistance.

Assuming:
V

IN

= 10V, V

OUT

= 5V, I

OUT

= 1.5A, TA = 50°C/W,

θ

Heatsink Case

= 6°C/W, θ

Heatsink Case

= 0.5°C/W, θ JC = 3°C/W

Power dissipation under this condition
P

D

= (VIN – V

OUT

) * I

OUT

= 7.5W

Junction Temperature
T

J

= TA + PD * (θ

Case - HS

+ θ

HS

+ θ JC)

For the Control Sections
T

J

= 50 + 7.5*(0.5+6=3) = 121.25°C

121.25°C < T

J (max)

for the Control & Power Sections.

In both case reliable operation is insured by adequate junction
temperature.

Rev. 10/30/00

SPX2810

Basic Adjustable Regulator

Output Voltage

Consider Figure 2. The resistance R

1

generates a constant
current flow, normally the specified load current of 10mA.
This current will go through the resistance R

2

to set the overall

output voltage. The current I

ADJ

is very small and constant.
Therefore its contribution to the overall output voltage is very
small and can generally be ignored.

Load Regulation

Parasitic line resistance can degrade load regulation. In order
not to affect the behavior of the regulator, it is best to connect
directly the R

1

resistance from the resistor divider to the case,

and not to the load. For the same reason, it is best to connect
the resistor R

2

to the Negative side of the load.

Output Voltage

The fixed voltage LDO voltage regulator are simple to use
regulators since the V

OUT

is preset to the specifications. It is
important however, to provide the proper output capacitance
for stability and improvement. For most operating conditions
a capacitance of 22uF tantalum or 100uF electrolytic will
ensure stability and prevent oscillation.

SPX2810

Fig.2 Basic Adjustable Regulator

V

IN

V

REF

V

OUT

= V

REF

* ( 1 + R2/R1) + I

ADJ

* R

2

I

ADJ

50µA

V

OUT

R

2

R

1

SPX2810

Fig.3 Basic Adjustable Regulator

V

IN

R

2

R

1

Connect R2 to Load

R

L

Connect R1 to

Case of Regulator

R

P

Parasitic Line

Resistance

SPX2810

Basic Fixed Regulator

V

IN

V

OUT

5V

C1

10uF

C2

10uF

3.3V

Rev. 10/30/00

SPX2810

TYPICAL APPLICATIONS

IN

OUT

ADJ

SPX2810

C

1

R

1

V

OUT

Fig. 5 Typical Adjustable Regulator

V

IN

LOAD

ADJ

SPX2810

Fig. 4 1A Current output Regulator

V

IN

C

1

OUT

IN

R

2

C

2

V

OUT

= V

REF

(1 + R2 ) + I

ADJ R2

R

1

R

1

Note A: V

IN(MIN)

= (Intended V

OUT

) + (V

DROPOUT (MAX)

)

SPX2810

Fig. 6 Improving Ripple Rejection

V

IN

R

1

R

2

150µF

10µF*

121Ω

1%

365Ω

1%

+

+

10µF

C

1

*C1 improves ripple rejection. Xc

should be ~ R

1

at ripple frequency.

5V

ADJ

IN OUT

(Note A)

V

OUT

SPX2810

Fig.7 5V Regulator with Shutdown

V

IN

100µF

121Ω

1%

365Ω

1%

+

+

10µF

5V

ADJ

IN OUT

(Note A)

1k

1k

TTL

Input

2N3904

Note A: V

IN(MIN)

= (Intended V

OUT

) + (V

DROPOUT (MAX)

)

Rev. 10/30/00

SPX2810

TYPICAL CHARACTERISTICS

Rev. 10/30/00

SPX2810

ORDERING INFORMATION

Ordering No Precision Output Voltage Packages

SPX2810U

2% Adj 3 Lead TO-220

SPX2810U-1.5

2% 1.5V 3 Lead TO-220

SPX2810U-2.5

2% 2.5V 3 Lead TO-220

SPX2810U-3.0

2% 3.0V 3 Lead TO-220

SPX2810U-3.3

2% 3.3V 3 Lead TO-220

SPX2810U-5.0

2% 5.0V 3 Lead TO-220

SPX2810AU

1% Adj 3 Lead TO-220

SPX2810AU-1.5

1% 1.5V 3 Lead TO-220

SPX2810AU-2.5

1% 2.5V 3 Lead TO-220

SPX2810AU-3.0

1% 3.0V 3 Lead TO-220

SPX2810AU-3.3

1% 3.3V 3 Lead TO-220

SPX2810AU-5.0

1% 5.0V 3 Lead TO-220

SPX2810T

2% Adj 3 Lead TO-263

SPX2810T-1.5

2% 1.5V 3 Lead TO-263

SPX2810T-2.5

2% 2.5V 3 Lead TO-263

SPX2810T-3.0

2% 3.0V 3 Lead TO-263

SPX2810T-3.3

2% 3.3V 3 Lead TO-263

SPX2810T-5.0

2% 5.0V 3 Lead TO-263

SPX1202AT

1% Adj 3 Lead TO-263

SPX2810AT-1.5

1% 1.5V 3 Lead TO-263

SPX2810AT-2.5

1% 2.5V 3 Lead TO-263

SPX2810AT-3.0

1% 3.0V 3 Lead TO-263

SPX2810AT-3.3

1% 3.3V 3 Lead TO-263

SPX2810AT-5.0

1% 5.0V 3 Lead TO-263

SPX2810M3

2% Adj 3 Lead TO-223

SPX2810M3-1.5

2% 1.5V 3 Lead TO-223

SPX2810M3-2.5

2% 2.5V 3 Lead TO-223

SPX2810M3-3.0

2% 3.0V 3 Lead TO-223

SPX2810M3-3.3

2% 3.3V 3 Lead TO-223

SPX2810M3-5.0

2% 5.0V 3 Lead TO-223

SPX2810AM3

1% Adj 3 Lead TO-223

SPX2810AM3-1.5

1% 1.5V 3 Lead TO-223

SPX2810AM3-2.5

1% 2.5V 3 Lead TO-223

SPX2810AM3-3.0

1% 3.0V 3 Lead TO-223

SPX2810AM3-3.3

1% 3.3V 3 Lead TO-223

SPX2810AM3-5.0

1% 5.0V 3 Lead TO-223

SPX2810R

2% Adj 3 Lead TO-252

SPX2810R-1.5

2% 1.5V 3 Lead TO-252

SPX2810R-2.5

2% 2.5V 3 Lead TO-252

SPX2810R-3.0

2% 3.0V 3 Lead TO-252

SPX2810R-3.3

2% 3.3V 3 Lead TO-252

SPX2810R-5.0

2% 5.0V 3 Lead TO-252

SPX2810AR

1% Adj 3 Lead TO-252

SPX2810AR-1.5

1% 1.5V 3 Lead TO-252

SPX2810AR-2.5

1% 2.5V 3 Lead TO-252

SPX2810AR-3.0

1% 3.0V 3 Lead TO-252

SPX2810AR-3.3

1% 3.3V 3 Lead TO-252

SPX2810AR-5.0

1% 5.0V 3 Lead TO-252

Rev. 10/30/00

SPX2810

SIGNAL PROCESSING EXCELLENCE

Sipex Corporation

Headquarters and Main Offices:

22 Linnell Circle
Billerica, MA 01821
TEL: [phone]
FAX: [phone]
e-mail: [e-mail]

233 South Hillview Drive
Milpitas, CA 95035
TEL: [phone]
FAX: [phone]

Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described
hereing; neither does it convey any license under its patent rights nor the rights of others.

Corporation