LM8364
LM8364 Micropower Undervoltage Sensing Circuits
Literature Number: SNVS232A
LM8364
Micropower Undervoltage Sensing Circuits
General Description
The LM8364 series are micropower undervoltage sensing
circuits that are ideal for use in battery powered micropro-
cessor based systems, where extended battery life is a key
requirement.
A range of threshold voltages from 2.0V to 4.5V are available
with an active low open drain output. These devices feature
a very low quiescent current of 0.65µA typical. The LM8364
series features a highly accurate voltage reference, a com-
parator with precise thresholds and built-in hysterisis to pre-
vent erratic reset operation, and guaranteed Reset operation
down to 1.0V with extremely low standby current.
These devices are available in the space saving SOT23
5-pin surface mount package. For other undervoltage
thresholds and output options, please contact National
Semiconductor.
Features
nExtremely Low Quiescent Current: 0.65µA, at V
IN
=
2.87V
nHigh Accuracy Threshold Voltage (±2.5%)
nOpen Drain Output
nInput Voltage Range: 1V to 6V
nSurface Mount Package (5-Pin SOT23)
nPin for pin compatible with MC33464
Applications
nLow Battery Detection
nMicroprocessor reset Controller
nPower Fail Indicator
nBattery Backup Detection
Functional Block Diagram
20065907
Connection Diagram
5-Pin SOT23
20065906
Top View
March 2005
LM8364 Micropower Undervoltage Sensing Circuits
© 2005 National Semiconductor Corporation DS200659 www.national.com
Pin Description
20065908
Ordering Information
Package Part Number Package
Marking
Threshold Output Type Transport Media NSC Drawing
5-Pin
SOT23
LM8364BALMF20 F01A 2.0V Open Drain,
Active Low
1k Units Tape and Reel
MF05A
LM8364BALMFX20 3k Units Tape and Reel
LM8364BALMF27 F15A 2.7V Open Drain,
Active Low
1k Units Tape and Reel
LM8364BALMFX27 3k Units Tape and Reel
LM8364BALMF30 F05A 3.0V Open Drain,
Active Low
1k Units Tape and Reel
LM8364BALMFX30 3k Units Tape and Reel
LM8364BALMF32 F16A 3.2V Open Drain,
Active Low
1k Units Tape and Reel
LM8364BALMFX32 3k Units Tape and Reel
LM8364BALMF45 F04A 4.5V Open Drain,
Active Low
1k Units Tape and Reel
LM8364BALMFX45 3k Units Tape and Reel
LM8364
www.national.com 2
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage −0.3V to 6.5V
RESET Output Voltage −0.3V to 6.5V
RESET Output Current 70mA
Storage Temperature Range −65˚C to 150˚C
Mounting Temp.
Lead temp (Soldering, 10 sec) 260˚C
Junction Temperature 125˚
Operating Ratings (Note 1)
Temperature Range −40˚C to 85˚C
Thermal Resistance to ambient (θ
JA
) 265˚C/W
ESD Tolerance
Human Body Model 2000V
Machine Model 200V
Electrical Characteristics
Unless otherwise specified, all limits guaranteed for T
A
= 25˚C.
Symbol Parameter Conditions Min
(Note 3)
Typ
(Note 2)
Max
(Note 3)
Units
V
DET−
Detector Threshold Voltage High to Low State Output
(V
IN
Decreasing)
V
20 Suffix 1.950 2.0 2.050
27 Suffix 2.633 2.7 2.767
30 Suffix 2.925 3.0 3.075
32 Suffix 3.120 3.2 3.280
45 Suffix 4.388 4.5 4.613
V
HYS
Detector Threshold
Hysteresis
V
IN
Increasing
V
20 Suffix 0.060 0.100 0.140
27 Suffix 0.081 0.135 0.189
30 Suffix 0.090 0.150 0.210
32 Suffix 0.096 0.160 0.224
45 Suffix 0.135 0.225 0.315
∆Vdet/∆T Detector Threshold Voltage
Temperature Coefficient ±100 PPM/˚C
V
OL
RESET Output Voltage Low
State
(Open Drain Output: I
SINK
= 1mA) 0.25 0.5 V
I
OL
RESET Output Sink Current V
IN
= 1.5V, V
OL
= 0.5V 1.0 2.5 mA
V
IN
Operating Input Voltage
Range 1.0 6.0 V
I
IN
Quiescent Input Current 20 Suffix
µA
V
IN
= 1.9V 0.55 0.8
V
IN
= 4.0V 0.70 1.3
27 Suffix
V
IN
= 2.6V 0.62 0.9
V
IN
= 4.7V 0.75 1.3
30 Suffix
V
IN
= 2.87V 0.65 0.9
V
IN
= 5.0V 0.77 1.3
32 Suffix
V
IN
= 3.08V 0.66 0.9
V
IN
= 5.20V 0.79 1.3
45 Suffix
V
IN
= 4.34V 0.70 1.0
V
IN
= 6.0 0.85 1.4
t
p
Propagation Delay Time
Figure 1
60 300 µs
LM8364
www.national.com3
Electrical Characteristics (Continued)
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 2: Typical values represent the most likely parametric norm
Note 3: All limits are guaranteed by testing or statistical analysis.
LM8364
www.national.com 4
Typical Performance Characteristics
Input Current vs. Input Voltage
LM8364BALMF45
Reset Output Voltage vs. Input Voltage
LM8364BALMF45
20065901 20065902
Reset Output Sink Current vs. Input Voltage
LM8364BALMF45
Reset Output Sink Current vs. Output Voltage
LM8364BALMF45
20065903 20065904
Detector Threshold Voltage vs. Temperature
LM8364BALMF45
20065905
LM8364
www.national.com5
Application Notes
The propagation delay time for the LM8364 is measured
using a 470kΩpull-up resistor connected to from the RESET
output pin to 5V in addition to a 10pF capacitive load con-
nected from the same pin to GND. Figure 1 shows the timing
diagram for the measurement for the propagation delay.
V
DET+
is equal to the sum of the detector threshold, V
DET−
,
and the built in hysteresis, V
HYS
.
The LM8364 ultra-low current voltage detector was designed
to monitor voltages and to provide an indication when the
monitored voltage, V
IN
, dropped below a precisely trimmed
threshold voltage. This characteristic is displayed in the typi-
cal operating timing diagram below. V
IN
is the voltage that is
being monitored and a pull up resistor is connected from the
RESET output pin to V
IN
.V
IN
is at some value above V
DET+
and then begins to decrease. Since this is an Active Low
device the RESET output is pulled High through the pull-up
resistor and tracks V
IN
until V
IN
crosses the trimmed thresh-
old V
DET−
. At this point the LM8364 recognizes that V
IN
is
now in a fault condition and the output immediately changes
to the Logic Low State. The RESET output will remain in this
low state until V
IN
increases above the threshold V
DET−
+
V
HYS
. This point is also known as V
DET+
as indicated earlier.
This built-in hysteresis has been added to the design to help
prevent erratic reset operation when the input voltage
crosses the threshold.
The LM8364 has a wide variety of applications that can take
advantage of its precision and low current consumption to
monitor Input voltages even though it was designed as a
reset controller in portable microprocessor based systems. It
is a very cost effective and space saving device that will
protect your more expensive investments of microproces-
sors and other devices that need a guaranteed supply volt-
age for proper operation.
20065909
FIGURE 1. Propagation Delay Timing Diagrams
20065910
FIGURE 2. Timing Waveforms
LM8364
www.national.com 6
Typical Applications
20065911
Microprocessor Reset Circuit
20065912
Dual Power Supply Undervoltage Supervision
LM8364
www.national.com7
Typical Applications (Continued)
20065913
Microcontroller System Load Sensing
20065914
LED Bar Graph Voltage Monitor
LM8364
www.national.com 8
Physical Dimensions inches (millimeters)
unless otherwise noted
5-Pin SOT23
NSC Package Number MF05A
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.
For the most current product information visit us at www.national.com.
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS
WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body, or
(b) support or sustain life, and whose failure to perform when
properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to result
in a significant injury to the user.
2. A critical component is any component of a life support
device or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain
no ‘‘Banned Substances’’ as defined in CSP-9-111S2.
National Semiconductor
Americas Customer
Support Center
Email: new.feedback@nsc.com
Tel: 1-800-272-9959
National Semiconductor
Europe Customer Support Center
Fax: +49 (0) 180-530 85 86
Email: europe.support@nsc.com
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
National Semiconductor
Asia Pacific Customer
Support Center
Email: ap.support@nsc.com
National Semiconductor
Japan Customer Support Center
Fax: 81-3-5639-7507
Email: jpn.feedback@nsc.com
Tel: 81-3-5639-7560
www.national.com
LM8364 Micropower Undervoltage Sensing Circuits
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements,
and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should
obtain the latest relevant information before placing orders and should verify that such information is current and complete. All products are
sold subject to TI’s terms and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with TI’s standard
warranty. Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty. Except where
mandated by government requirements, testing of all parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for their products and
applications using TI components. To minimize the risks associated with customer products and applications, customers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right, copyright, mask work right,
or other TI intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
published by TI regarding third-party products or services does not constitute a license from TI to use such products or services or a
warranty or endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual
property of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied
by all associated warranties, conditions, limitations, and notices. Reproduction of this information with alteration is an unfair and deceptive
business practice. TI is not responsible or liable for such altered documentation. Information of third parties may be subject to additional
restrictions.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that product or service voids all
express and any implied warranties for the associated TI product or service and is an unfair and deceptive business practice. TI is not
responsible or liable for any such statements.
TI products are not authorized for use in safety-critical applications (such as life support) where a failure of the TI product would reasonably
be expected to cause severe personal injury or death, unless officers of the parties have executed an agreement specifically governing
such use. Buyers represent that they have all necessary expertise in the safety and regulatory ramifications of their applications, and
acknowledge and agree that they are solely responsible for all legal, regulatory and safety-related requirements concerning their products
and any use of TI products in such safety-critical applications, notwithstanding any applications-related information or support that may be
provided by TI. Further, Buyers must fully indemnify TI and its representatives against any damages arising out of the use of TI products in
such safety-critical applications.
TI products are neither designed nor intended for use in military/aerospace applications or environments unless the TI products are
specifically designated by TI as military-grade or "enhanced plastic."Only products designated by TI as military-grade meet military
specifications. Buyers acknowledge and agree that any such use of TI products which TI has not designated as military-grade is solely at
the Buyer's risk, and that they are solely responsible for compliance with all legal and regulatory requirements in connection with such use.
TI products are neither designed nor intended for use in automotive applications or environments unless the specific TI products are
designated by TI as compliant with ISO/TS 16949 requirements. Buyers acknowledge and agree that, if they use any non-designated
products in automotive applications, TI will not be responsible for any failure to meet such requirements.
Following are URLs where you can obtain information on other Texas Instruments products and application solutions:
Products Applications
Audio www.ti.com/audio Communications and Telecom www.ti.com/communications
Amplifiers amplifier.ti.com Computers and Peripherals www.ti.com/computers
Data Converters dataconverter.ti.com Consumer Electronics www.ti.com/consumer-apps
DLP®Products www.dlp.com Energy and Lighting www.ti.com/energy
DSP dsp.ti.com Industrial www.ti.com/industrial
Clocks and Timers www.ti.com/clocks Medical www.ti.com/medical
Interface interface.ti.com Security www.ti.com/security
Logic logic.ti.com Space, Avionics and Defense www.ti.com/space-avionics-defense
Power Mgmt power.ti.com Transportation and Automotive www.ti.com/automotive
Microcontrollers microcontroller.ti.com Video and Imaging www.ti.com/video
RFID www.ti-rfid.com
OMAP Mobile Processors www.ti.com/omap
Wireless Connectivity www.ti.com/wirelessconnectivity
TI E2E Community Home Page e2e.ti.com
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright ©2011, Texas Instruments Incorporated
