Datasheet LM8364BALMF20, LM8364BALMFX45, LM8364BALMF45, LM8364BALMF30, LM8364BALMFX20 Datasheet (NSC)

LM8364
Micropower Undervoltage Sensing Circuits

LM8364 Micropower Undervoltage Sensing Circuits

March 2003

General Description

The LM8364 series are micropower undervoltage sensing
circuits that are ideal for use in battery powered micropro­cessor 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 com­parator with precise thresholds and built-in hysterisis to pre­vent 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.

Functional Block Diagram

Features

n Extremely Low Quiescent Current: 0.65µA, at VIN=

2.87V

n High Accuracy Threshold Voltage (
n Open Drain Output
n Input Voltage Range: 1V to 6V
n Surface Mount Package (5-Pin SOT23)
n Pin for pin compatible with MC33464

±

2.5%)

Applications

n Low Battery Detection
n Microprocessor reset Controller
n Power Fail Indicator
n Battery Backup Detection

Connection Diagram

5-Pin SOT23

Top View

20065907

© 2003 National Semiconductor Corporation DS200659 www.national.com

20065906

Pin Description

LM8364

Ordering Information

20065908

Package Part Number Package

Marking

5-Pin

SOT23

LM8364BALMF20

LM8364BALMFX20 3k Units Tape and Reel

LM8364BALMF30

LM8364BALMFX30 3k Units Tape and Reel

LM8364BALMF45

LM8364BALMFX45 3k Units Tape and Reel

F01A 2.0V

F05A 3.0V

F04A 4.5V

Threshold Output Type Transport Media NSC Drawing

Open Drain,

Active Low

Open Drain,

Active Low

Open Drain,

Active Low

1k Units Tape and Reel

1k Units Tape and Reel

1k Units Tape and Reel

MF05A

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LM8364

Absolute Maximum Ratings (Note 1)

Junction Temperature 125˚

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

RESET Output Current

−0.3V to 6.5V

70mA

Storage Temperature Range −65˚C to 150˚C

Mounting Temp.

Operating Ratings (Note 1)

Temperature Range −40˚C to 85˚C

Thermal Resistance to ambient (θ

ESD Tolerance

Human Body Model 2000V

Machine Model 200V

) 265˚C/W

JA

Lead temp (Soldering, 10 sec) 260˚C

Electrical Characteristics

Unless otherwise specified, all limits guaranteed for TA= 25˚C.

Symbol Parameter Conditions Min

(Note 3)

V

DET−

Detector Threshold Voltage High to Low State Output

Decreasing)

(V

IN

20 Suffix 1.950 2.0 2.050

30 Suffix 2.925 3.0 3.075

45 Suffix 4.388 4.5 4.613

V

HYS

Detector Threshold
Hysteresis

VINIncreasing

20 Suffix 0.060 0.100 0.140

30 Suffix 0.090 0.150 0.210

45 Suffix 0.135 0.225 0.315

∆Vdet/∆T Detector Threshold Voltage

Temperature Coefficient

V

OL

RESET Output Voltage Low

(Open Drain Output: I

= 1mA) 0.25 0.5 V

SINK

State

I

OL

V

IN

I

IN

RESET Output Sink Current VIN= 1.5V, VOL= 0.5V 1.0 2.5 mA

Operating Input Voltage
Range

1.0 6.0 V

Quiescent Input Current 20 Suffix

V

= 1.9V 0.55 0.8

IN

V

= 4.0V 0.70 1.3

IN

30 Suffix

V

= 2.87V 0.65 0.9

IN

V

= 5.0V 0.77 1.3

IN

45 Suffix

V

= 4.34V 0.70 1.0

IN

V

= 6.0 0.85 1.4

IN

t

p

Propagation Delay Time

Figure 1

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.

Typ

(Note 2)

±

100 PPM/˚C

Max

(Note 3)

60 300 µs

Units

V

V

µA

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Typical Performance Characteristics

LM8364

Input Current vs. Input Voltage

LM8364BALMF45

Reset Output Voltage vs. Input Voltage

LM8364BALMF45

20065901

Reset Output Sink Current vs. Input Voltage

LM8364BALMF45

20065903 20065904

Detector Threshold Voltage vs. Temperature

LM8364BALMF45

20065902

Reset Output Sink Current vs. Output Voltage

LM8364BALMF45

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Application Notes

The propagation delay time for the LM8364 is measured
using a 470kΩ pull-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.

is equal to the sum of the detector threshold, V

V

DET+

and the built in hysteresis, V

HYS

.

20065909

DET−

LM8364

,

FIGURE 1. Propagation Delay Timing Diagrams

The LM8364 ultra-low current voltage detector was designed
to monitor voltages and to provide an indication when the
monitored voltage, V

, dropped below a precisely trimmed

IN

threshold voltage. This characteristic is displayed in the typi­cal operating timing diagram below. V

is the voltage that is

IN

being monitored and a pull up resistor is connected from the
RESET output pin to V

is at some value above V

IN.VIN

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 VINuntil VINcrosses the trimmed thresh­old V

. At this point the LM8364 recognizes that VINis

DET−

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 VINincreases above the threshold V

DET−

V

. This point is also known as V

HYS

as indicated earlier.

DET+

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 microproces­sors and other devices that need a guaranteed supply volt­age for proper operation.

+

FIGURE 2. Timing Waveforms

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Typical Applications

LM8364

Microprocessor Reset Circuit

20065911

Dual Power Supply Undervoltage Supervision

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20065912

Typical Applications (Continued)

LM8364

Microcontroller System Load Sensing

20065913

LED Bar Graph Voltage Monitor

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Physical Dimensions inches (millimeters)

unless otherwise noted

LM8364 Micropower Undervoltage Sensing Circuits

5-Pin SOT23

NSC Package Number MF05A

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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.