500mA Low-Noise LDO Voltage Regulator
500mA Low-
Noise LDO Voltage Regulator
August 2016
Rev. 2.0.3
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 O utput 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
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 2/12 Rev. 2.0.3
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
Stor age Temperature .............................. -65°C to 150°C
Junction Temperature .......................................... 150°C
Power Dissipation ................................ Inter nally Limite d
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 all owable power limit w ill result in exc essiv e
die temperature; thus, the regulator will go into thermal
shutdown
ELECTRICAL SP ECIFICATIONS
Spec ificatio ns with standard typ e are for an Operating Junction Te mperature 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,
desig n, or statis tic a l c or relation. Typ ic al values re pr ese nt the most likely parame tric nor m at TJ = 25°C, and are provided for
reference purposes only . Unless o therwise indic ated, VIN = VOUT + 1V (VIN = VOUT + 1.2 V for 1.2V o ption), IL = 100µA, CL =
1µF, VEN ≥ 2.5V, TA= TJ = 25°C.
Parameter Min. Typ. Max. Units Conditions
Output Voltag e Tole rance
-1
+1
%
-2
+2
•
Output Voltag e Temperature
Coefficient
57 ppm/°C
Line Regulatio n
0.04
0.1
%/V
VIN = VOUT +1 to 16V and VEN ≤ 6V
0.2
•
VIN = VEN = VOUT +1 ≤ 8V
0.2
V
IN
= V
EN
= V
OUT
+1 ≤16V
TA = 25°C to 85°C
Load Regulation
0.05
0.4
%
IL = 0.1mA t o 50 0mA
Dropout Vo lta g e (VIN-VOUT) 2
10
60
mV
IL = 100µA
80
•
125
175
IL = 50mA
250
•
180
350
IL = 1 50mA
450
•
340
550
IL = 5 00mA
700
•
Quiescent Current (IGND)
0.05
3
µA
VENABLE ≤ 0.4V
8
•
VENABLE = 0.25V
Ground Pin C urrent (IGND)
90
150
µA
IL = 100µA
190
•
250
650
IL = 50mA
900
•
1.0
2.0
mA
IL = 1 50mA
2.5
•
6.5
25.0
IL = 5 00mA
30.0
•
Ripp le Reje c tion (PSRR)
70
dB
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 3/12 Rev. 2.0.3
Parameter Min. Typ. Max. Units Conditions
Current Limit (ILIMIT)
800
mA
VOUT=0V
950
•
Output No ise (e NO) 300 µVRMS IL = 10m A, CL = 1.0µF, CIN = 1µF,
(10Hz – 100kHz)
40 µVRMS IL = 10m A, CL = 1.0µF, CBYP = 1µF,
CIN = 1µF, (10Hz – 100kHz)
Input Vo ltag e Leve l Log ic Low
(V
IL
)
0.4 V OFF
Input Vo ltag e Leve l Log ic High
(VIH) 2 V ON
ENABLE Input Current
0.01
2
µA
VIL ≤ 0.4V
VIH ≥ 2.0V
3
20
Note 2: Not applica b le to output voltage 2V or less.
PIN ASSIGNMENT
Fig. 2: SPX3819 Pin Ass ignment
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(inp ut). C MO S co mp a tible co ntr ol input. Logic high –
enable;
logic low or ope n = shutdown
ADJ/BYP 4 8 4 Adjust(input). Fee db ac k input. Connect to resistive voltage-divider
network
NC
-
2, 4, 6
-
No Connect
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 4/12 Rev. 2.0.3
ORDERING INFORMATION
Part Number Temperature
Range Marking Package Packaging
Method Note 1 Note 2
SPX3819M5-L
-40°C≤TJ≤+125°C G1WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L/TR
Tape & Reel
SPX3819M5-L-1-2
-40°C≤TJ≤+125°C A4WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L-1-2/TR
Tape & Reel
SPX3819M5-L-1-5
-40°C≤TJ≤+125°C W3WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L-1-5/TR
Tape & Reel
SPX3819M5-L-1-8
-40°C≤TJ≤+125°C G3WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L-1-8/TR
Tape & Reel
SPX3819M5-L-2-5 -40°C≤TJ≤+125°C H3WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L-2-5/TR
Tape & Reel
SPX3819M5-L-3-0
-40°C≤TJ≤+125°C J3WW SOT-23-5 Bulk Halogen free
SPX3819M5-L-3-0/TR
Tape & Reel
SPX3819M5-L-3-3
-40°C≤TJ≤+125°C L3WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L-3-3/TR
Tape & Reel
SPX3819M5-L-5-0
-40°C≤TJ≤+125°C M3WW SOT-23-5
Bulk
Halogen free
SPX3819M5-L-5-0/TR
Tape & Reel
SPX3819R2-L -40°C≤TJ≤+125°C
L0L
YWW
XX
DFN-8 Bulk Halogen free
SPX3819R2-L/TR Tape & Reel
SPX3819R2-L-1-2 -40°C≤TJ≤+125°C
M0L
YWW
XX
DFN-8 Bulk Halogen free
SPX3819R2-L-1-2/TR
Tape & Reel
SPX3819R2-L-1-8
-40°C≤TJ≤+125°C
N0L
YWW
XX
DFN-8
Bulk
Halogen free
SPX3819R2-L-1-8/TR
Tape & Reel
SPX3819S-L -40°C≤TJ≤+125°C
SPX3819
YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L/TR Tape & Reel
SPX3819S-L-1-2 -40°C≤TJ≤+125°C
SPX3819
12YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L-1-2/TR Tape & Reel
SPX3819S-L-1-5 -40°C≤TJ≤+125°C
SPX3819
15YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L-1-5/TR Tape & Reel
SPX3819S-L-1-8 -40°C≤TJ≤+125°C
SPX3819
18YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L-1-8/TR Tape & Reel
SPX3819S-L-2-5 -40°C≤TJ≤+125°C
SPX3819
25YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L-2-5/TR Tape & Reel
SPX3819S-L-3-3 -40°C≤TJ≤+125°C
SPX3819
33YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L-3-3/TR Tape & Reel
SPX3819S-L-5-0 -40°C≤TJ≤+125°C
SPX3819
50YYWWL
XXX
NSOIC-8 Bulk Halogen free
SPX3819S-L-5-0/TR Tape & Reel
Refer to www.exar.com/SPX3819 f or m ost up-to-date Ordering Information
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 5/12 Rev. 2.0.3
TYPICA L P ERFORMANCE CHARACTERISTICS
Fig. 3: Gro und Curre nt vs Load C urrent
Fig. 4: Ground Current vs Input Voltage
Fig. 5 Ground Current vs Load Current in Dropout
Fig. 6 Outp ut Volta g e vs Inp ut Voltage
Fig. 7 Dropo ut Vo ltage vs Load Current
Fig. 8 Outp ut Volta g e vs Lo ad Curre nt
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 6/12 Rev. 2.0.3
Fig. 9 Ground Current vs Temperature with 100μA Load
Fig. 10 Ground Current vs Tempe rature with 50mA Load
Fig. 11 Ground Current vs Tempe rature with 500mA Load
Fig. 12 Ground Current vs Tempe rature in Dropout
Fig. 13 ENABLE Voltage, ON threshold, vs Input Voltage
Fig. 14 Output Voltage vs Temperature
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 7/12 Rev. 2.0.3
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 decre ases with higher output curre nts.
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 o n type and manufactur er. 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 r ampup
of the output voltage should use a larger CBYP.
However, if a rapid turn-on is necessary, the
BYP capacitor can be omitted.
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 8/12 Rev. 2.0.3
The SPX3819’s internal reference is available
throug h t he BYP pin.
Figure 18 represents a SPX3819 standard
application circu it. The EN (e nable) pin is pulled
high (>2.0V) to enable the regulator. To disable
the regulator, EN < 0.4V.
Fig. 18: Standard Applic ation 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: Typic a l Adj us table Output Voltag e Conf iguration
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 9/12 Rev. 2.0.3
PACKAGE SPECIFICATION 8-PIN SOICN
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 10/12 Rev. 2.0.3
8-PIN 2X3 DFN
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 11/12 Rev. 2.0.3
5-PIN SOT-23
SPX3819
500mA Low-Noise LDO Voltage Regulat
or
© 2013-2016 Exar Corpor a tion 12/12 Rev. 2.0.3
REVISION HISTORY
Revision Date Description
2.0.0 08/23/12 Reformat of Datasheet
Addition of SPX3819R2-L and SPX3819R2-L/TR part numbers
2.0.1
12/02/13
Added Stora ge Te mper atur e Rang e and Junctio n Temperature in ABS MAX Ratings.
2.0.2 05/20/14
Updated package dra wi n gs and corrected DFN-8 package marking information
[ECN 142 3-03 6/3/14]
2.0.3
08/31/16
Updated log o and Ordering Information table.
FOR FURTHER ASSISTANCE
Email: customersupport@exar.com
powertechsupport@exar.com
Exar Technical Do cumentation: https://www.exar.com/technical-documentation
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,
perfor mance or reliability. EXAR Corp oration assumes no respons ibility for the use of any circuits des cribed 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 herein are only for illustration purposes and may vary depending upon a user’s specific
applica tion. While the inform ation in this publicatio n has been carefully c hecked; 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
malfunctio n of the pro d uc t c an re as onably be exp ected to cause failure of the life support sy s te m or to s ig ni f ic a ntly affect its
safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing,
assurances to its sa tisfa c tio n that: (a) the r is k of injur y or damage has bee n minimized; (b) the use r as s um es all s uc h risks ;
(c) pote ntial li ab ility of EXAR Corpor ation is adequately pro tecte d und e r the cir c umstances.
Reprod uc tio n, in part or whole, without the prior wr itte n consent of EXAR Corpo ration is prohibite d .
