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August 2012
Rev. 2.0.0
Exar Corporation www.exar.com
48720 Kato Road, Fremont CA 94538, USA Tel. +1 510 668-7000 – Fax. +1 510 668-7001
GENERAL DESCRIPTION
The SPX3819 is a positive voltage regulator
with a low dropout voltage and low noise
output. In addition, this device offers a very
low ground current of 800μA at 100mA output.
The SPX3819 has an initial tolerance of less
than 1% max and a logic compatible ON/OFF
switched input. When disabled, power
consumption drops to nearly zero. Other key
features include reverse battery protection,
current limit, and thermal shutdown. The
SPX3819 includes a reference bypass pin for
optimal low noise output performance. With its
very low output temperature coefficient, this
device also makes a superior low power
voltage reference.
The SPX3819 is an excellent choice for use in
battery-powered applications such as cordless
telephones, radio control systems, and
portable computers. It is available in several
fixed output voltage options or with an
adjustable output voltage.
This device is offered in 8 pin NSOIC, 8 pin
DFN and 5-pin SOT-23 packages.
APPLICATIONS
Portable Consumer Equipment
Portable Instrumentation
Industrial Equipment
SMPS Post Regulators
FEATURES
Low Noise: 40μV Possible
High Accuracy: 1%
Reverse Battery Protection
Low Dropout: 340mV at Full Load
Low Quiescent Current: 90μA
Zero Off-Mode Current
Fixed & Adjustable Output Voltages:
1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.3V & 5.0V
Fixed Output Voltages
≥1.235V Adjustable Output Voltages
Available in RoHS Compliant, Lead Free
Packages:
5-pin SOT-23, 8-pin SOIC and 8-pin DFN
TYPICAL APPLICATION DIAGRAM
Fig. 1: SPX3819 Application Circuit
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© 2012 Exar Corporation 2/12 Rev. 2.0.0
ABSOLUTE MAXIMUM RATINGS
These are stress ratings only and functional operation of
the device at these ratings or any other above those
indicated in the operation sections of the specifications
below is not implied. Exposure to absolute maximum
rating conditions for extended periods of time may affect
reliability.
VIN, EN ..................................................... -20V to +20V
Power Dissipation ................................ Internally Limited
Lead Temperature (Soldering, 5 sec) ..................... 260°C
ESD Rating (HBM - Human Body Model) .................... 2kV
OPERATING RATINGS
Input Voltage Range VIN ................................ 2.5V to 16V
Enable Pin EN ............................................... 0.0V to VIN
Junction Temperature Range ................. -40°C to +125°C
Thermal Resistance1 .....................................................
θJA (SOT23-5) ...............................................191°C/W
θJA (NSOIC-8) ............................................ 128.4°C/W
θJA (DFN-8) ................................................... 59°C/W
Note 1: The maximum allowable power dissipation is a
function of maximum operating junction temperature,
TJ(max) the junction to ambient thermal resistance, and the
ambient θJA, and the ambient temperature TA. The
maximum allowable power dissipation at any ambient
temperature is given: PD(max) = (TJ(max)-TA)/θJA, exceeding
the maximum allowable power limit will result in excessive
die temperature; thus, the regulator will go into thermal
shutdown
ELECTRICAL SPECIFICATIONS
Specifications with standard type are for an Operating Junction Temperature of TJ = 25°C only; limits applying over the full
Operating Junction Temperature range are denoted by a “•”. Minimum and Maximum limits are guaranteed through test,
design, or statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for
reference purposes only. Unless otherwise indicated, VIN = VOUT + 1V (VIN = VOUT + 1.2V for 1.2V option), IL = 100µA, CL =
1µF, VEN ≥ 2.5V, TA= TJ = 25°C.
Parameter
Min.
Typ.
Max.
Units
Conditions
Output Voltage Tolerance
-1
+1
%
-2
+2
•
Output Voltage Temperature
Coefficient
57
ppm/°C
Line Regulation
0.04
0.1
%/V
VIN = VOUT +1 to 16V and VEN ≤ 6V
0.2
•
VIN = VEN = VOUT +1 ≤ 8V
0.2
VIN = VEN = VOUT +1 ≤16V
TA = 25°C to 85°C
Load Regulation
0.05
0.4
%
IL = 0.1mA to 500mA
Dropout Voltage (VIN-VOUT) 2
10
60
mV
IL = 100µA
80
•
125
175
IL = 50mA
250
•
180
350
IL = 150mA
450
•
340
550
IL = 500mA
700
•
Quiescent Current (IGND)
0.05
3
µA
VENABLE ≤ 0.4V
8
•
VENABLE = 0.25V
Ground Pin Current (IGND)
90
150
µA
IL = 100µA
190
•
250
650
IL = 50mA
900
•
1.0
2.0
mA
IL = 150mA
2.5
•
6.5
25.0
IL = 500mA
30.0
•
Ripple Rejection (PSRR)
70
dB
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© 2012 Exar Corporation 3/12 Rev. 2.0.0
Parameter
Min.
Typ.
Max.
Units
Conditions
Current Limit (ILIMIT)
800
mA
VOUT=0V
950
•
Output Noise (eNO)
300
µVRMS
IL = 10mA, CL = 1.0µF, CIN = 1µF,
(10Hz – 100kHz)
40
µVRMS
IL = 10mA, CL = 1.0µF, CBYP = 1µF,
CIN = 1µF, (10Hz – 100kHz)
Input Voltage Level Logic Low
(VIL)
0.4
V
OFF
Input Voltage Level Logic High
(VIH)
2
V
ON
ENABLE Input Current
0.01
2
µA
VIL ≤ 0.4V
VIH ≥ 2.0V
3
20
Note 2: Not applicable to output voltage 2V or less.
PIN ASSIGNMENT
Fig. 2: SPX3819 Pin Assignment
PIN DESCRIPTION
Name
Pin #
nSOIC
Pin #
DFN
Pin #
SOT-23
Description
VIN
2
3
1
Supply Input
GND
5, 6, 7, 8
7
2
Ground
VOUT
3
5
5
Regulator Output
EN
1
1
3
Enable(input). CMOS compatible control input. Logic high – enable;
logic low or open = shutdown
ADJ/BYP
4
8
4
Adjust(input). Feedback input. Connect to resistive voltage-divider
network
NC
-
2, 4, 6
-
No Connect
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© 2012 Exar Corporation 4/12 Rev. 2.0.0
ORDERING INFORMATION
Part Number
Temperature
Range
Marking
Package
Packing
Quantity
Note 1
Note 2
SPX3819M5-L
-40°C≤TJ≤+125°C
G1WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L/TR
2.5K/Tape & Reel
SPX3819M5-L-1-2
-40°C≤TJ≤+125°C
A4WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-1-2/TR
2.5K/Tape & Reel
SPX3819M5-L-1-5
-40°C≤TJ≤+125°C
W3WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-1-5/TR
2.5K/Tape & Reel
SPX3819M5-L-1-8
-40°C≤TJ≤+125°C
G3WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-1-8/TR
2.5K/Tape & Reel
SPX3819M5-L-2-5
-40°C≤TJ≤+125°C
H3WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-2-5/TR
2.5K/Tape & Reel
SPX3819M5-L-3-0
-40°C≤TJ≤+125°C
J3WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-3-0/TR
2.5K/Tape & Reel
SPX3819M5-L-3-3
-40°C≤TJ≤+125°C
L3WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-3-3/TR
2.5K/Tape & Reel
SPX3819M5-L-5-0
-40°C≤TJ≤+125°C
M3WW
SOT-23-5
Bulk
Halogen free
SPX3819M5-L-5-0/TR
2.5K/Tape & Reel
SPX3819R2-L
-40°C≤TJ≤+125°C
L0
YWW
XXX
DFN-8
Bulk
Halogen free
SPX3819R2-L/TR
3.0K/Tape & Reel
SPX3819R2-L-1-2
-40°C≤TJ≤+125°C
M0
YWW
XXX
DFN-8
Bulk
Halogen free
SPX3819R2-L-1-5/TR
3.0K/Tape & Reel
SPX3819R2-L-1-8
-40°C≤TJ≤+125°C
N0
YWW
XXX
DFN-8
Bulk
Halogen free
SPX3819R2-L-1-8/TR
3.0K/Tape & Reel
SPX3819S-L
-40°C≤TJ≤+125°C
SPX3819
YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L/TR
2.5K/Tape & Reel
SPX3819S-L-1-2
-40°C≤TJ≤+125°C
SPX3819
12YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L-1-2/TR
2.5K/Tape & Reel
SPX3819S-L-1-5
-40°C≤TJ≤+125°C
SPX3819
15YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L-1-5/TR
2.5K/Tape & Reel
SPX3819S-L-1-8
-40°C≤TJ≤+125°C
SPX3819
18YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L-1-8/TR
2.5K/Tape & Reel
SPX3819S-L-2-5
-40°C≤TJ≤+125°C
SPX3819
25YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L-2-5/TR
2.5K/Tape & Reel
SPX3819S-L-3-3
-40°C≤TJ≤+125°C
SPX3819
33YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L-3-3/TR
2.5K/Tape & Reel
SPX3819S-L-5-0
-40°C≤TJ≤+125°C
SPX3819
50YYWWL
XXX
NSOIC-8
Bulk
Halogen free
SPX3819S-L-5-0/TR
2.5K/Tape & Reel
“YY” = Year – “WW” = Work Week – “X” = Lot Number; when applicable.
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© 2012 Exar Corporation 5/12 Rev. 2.0.0
TYPICAL PERFORMANCE CHARACTERISTICS
Fig. 3: Ground Current vs Load Current
Fig. 4: Ground Current vs Input Voltage
Fig. 5 Ground Current vs Load Current in Dropout
Fig. 6 Output Voltage vs Input Voltage
Fig. 7 Dropout Voltage vs Load Current
Fig. 8 Output Voltage vs Load Current
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© 2012 Exar Corporation 6/12 Rev. 2.0.0
Fig. 9 Ground Current vs Temperature with 100μA Load
Fig. 10 Ground Current vs Temperature with 50mA Load
Fig. 11 Ground Current vs Temperature with 500mA Load
Fig. 12 Ground Current vs Temperature in Dropout
Fig. 13 ENABLE Voltage, ON threshold, vs Input Voltage
Fig. 14 Output Voltage vs Temperature
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© 2012 Exar Corporation 7/12 Rev. 2.0.0
Fig. 15 Output Noise vs Bypass Capacitor Value IL = 10mA,
10Hz - 100kHz
Fig. 16 Line Transient Response for 3.3V Device
Fig. 17 Load Transient Response for 3.3V Device
APPLICATION INFORMATION
The SPX3819 requires an output capacitor for
device stability. Its value depends upon the
application circuit. In general, linear regulator
stability decreases with higher output
currents. In applications where the SPX3819 is
sourcing less current, a lower output
capacitance may be sufficient. For example, a
regulator outputting only 10mA, requires
approximately half the capacitance as the
same regulator sourcing 150mA.
Bench testing is the best method for
determining the proper type and value of the
capacitor since the high frequency
characteristics of electrolytic capacitors vary
widely, depending on type and manufacturer.
A high quality 2.2μF aluminum electrolytic
capacitor works in most application circuits,
but the same stability often can be obtained
with a 1μF tantalum electrolytic.
With the SPX3819 adjustable version, the
minimum value of output capacitance is a
function of the output voltage. The value
decreases with higher output voltages, since
closed loop gain is increased.
TYPICAL APPLICATIONS CIRCUITS
A 10nF capacitor on the BYP pin will
significantly reduce output noise, but it may
be left unconnected if the output noise is not a
major concern. The SPX3819 start-up speed is
inversely proportional to the size of the BYP
capacitor. Applications requiring a slow
rampup of the output voltage should use a
larger CBYP. However, if a rapid turn-on is
necessary, the BYP capacitor can be omitted.
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© 2012 Exar Corporation 8/12 Rev. 2.0.0
The SPX3819’s internal reference is available
through the BYP pin.
Figure 18 represents a SPX3819 standard
application circuit. The EN (enable) pin is
pulled high (>2.0V) to enable the regulator.
To disable the regulator, EN < 0.4V.
Fig. 18: Standard Application Circuit
The SPX3819 in Figure 19 illustrates a typical
adjustable output voltage configuration. Two
resistors (R1 and R2) set the output voltage.
The output voltage is calculated using the
formula:
VOUT = 1.235V x [1 + R1/R2]
R2 must be >10kΩ and for best results, R2
should be between 22kΩ and 47kΩ.
Fig. 19: Typical Adjustable Output Voltage Configuration
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© 2012 Exar Corporation 9/12 Rev. 2.0.0
PACKAGE SPECIFICATION
8-PIN SOICN
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© 2012 Exar Corporation 10/12 Rev. 2.0.0
8-PIN 2X3 DFN
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© 2012 Exar Corporation 11/12 Rev. 2.0.0
5-PIN SOT-23
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© 2012 Exar Corporation 12/12 Rev. 2.0.0
REVISION HISTORY
Revision
Date
Description
2.0.0
08/23/12
Reformat of Datasheet
Addition of SPX3819R2-L and SPX3819R2-L/TR part numbers
FOR FURTHER ASSISTANCE
Email: customersupport@exar.com
Exar Technical Documentation: http://www.exar.com/TechDoc/default.aspx?
EXAR CORPORATION
HEADQUARTERS AND SALES OFFICES
48720 Kato Road
Fremont, CA 94538 – USA
Tel.: +1 (510) 668-7000
Fax: +1 (510) 668-7030
www.exar.com
NOTICE
EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve
design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein,
conveys no license under any patent or other right, and makes no representation that the circuits are free of patent
infringement. Charts and schedules contained here in are only for illustration purposes and may vary depending upon a
user’s specific application. While the information in this publication has been carefully checked; no responsibility, however,
is assumed for inaccuracies.
EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or
malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its
safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in
writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all
such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances.
Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited.
