Intersil Corporation ICM7249 Datasheet

August 1997

ICM7249

51/2 Digit LCD,

Micro-Power Event/Hour Meter

Features

• Hour Meter Requires Only 4 Parts Total

• Micropower Operation: < 1µA at 2.8V (Typ)

1

• 10 Year Operation On One Lithium Cell. 2

/2 Year

Battery Life with Display Connected

• Directly Drives 5

1

/2 Digit LCD

• 14 Programmable Modes of Operation

• Times Hrs., 0.1 Hrs., 0.01 Hrs., 0.1 Mins.

• Counts 1’s, 10’s, 100’s, 1000’s

• Dual Function Input Circuit

- Selectable Debounce for Counter

- High-Pass Filter for Timer

• Direct AC Line Triggering with Input Resistor

• Winking “Timer Active” Display Output

• Display Test Feature

Applications

• AC or DC Hour Meters

• AC or DC Totalizers

• Portable Battery Powered Equipment

• Long Range Service Meters

Ordering Information

TEMP.

PART NUMBER

ICM7249IPM -20 to 85 48 Ld PDIP E48.6

RANGE (oC) PACKAGE

PKG.

NO.

Description

The ICM7249 Timer/Counter is intended for long-term
battery-supported industrial applications. The ICM7249
typically draws 1µA during active timing or counting, due to
Intersil’ special low-power design techniques. This allows
more than 10 years of continuous operation without battery
replacement. The chip offers four timing modes, eight
counting modes and four test modes.

The ICM7249 is a 48 lead device, powered by a single DC
voltage source and controlled by a 32.768kHz quartz crystal.
No other external components are required. Inputs to the
chip are TTL-compatible and outputs drive standard direct
drive LCD segments.

Pinout

ICM7249

(PDIP)

TOP VIEW

b6/c6

g5
e5
d5
c5
b5
a5

g4
e4
d4
c4
b4
a4

g3
e3
d3
c3
b3
a3

g2

1

f5

2
3
4
5
6
7
8

f4

9
10
11
12
13
14
15

f3

16
17
18
19
20
21
22
23

f2

24

48

DT
S/S

47

C3

46

C2

45

C1

44

C0

43

GND

42

OSC OUTPUT

41

OSC INPUT

40

V

39

DD

BP

38

W

37

a1

36

b1

35

c1

34

d1

33

e1

32

g1

31

f1

30

a2

29

b2

28

c2

27

d2

26

e2

25

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
http://www.intersil.com or 407-727-9207

| Copyright © Intersil Corporation 1999

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File Number 3170.1

Functional Block Diagram

ICM7249

OSC

OSC

OUT

6 SEC1Hz

IN

S/S

V+

V-

2

÷

1 SEG

DEC

B6 F5 G5 A1 W BP DT

OSC

VOLTAGE

REGLATOR

10

÷

44

7 SEG

DEC

10

÷

7 SEG

DEC

SWITCH

DEBOUNCE

÷

7 SEG

DEC

10

215DIVIDER

10

÷

7 SEG

DEC

32Hz

÷

7 SEG

DEC

6

÷

10

10

÷

WINK

SEG

÷

1Hz

6

÷

10

DISPLAY

TEST

DECODE

CONTROL

16

÷

C0

C1

C2

C3

10

32Hz

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ICM7249

Absolute Maximum Ratings Thermal Information

Supply Voltage (VDD - VSS). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6V

Input Voltage, Pins 43 - 48 (Note 1) . . (VSS- 0.3V) to (VDD+ 0.3V)

Operating Conditions

Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . -40oC to 85oC

CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation
of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.

NOTES:

1. Due to the SCR structure inherent in junction-isolated CMOS devices. the circuit can be put in a latchup mode it large currents are injected
into device inputs or outputs. For this reason special care should be taken in a system with multiple power supplies to prevent voltages
being applied to inputs or outputs before power is applied. If only inputs are aff ected, latchup also can be prev ented by limiting the current
into the input terminal to less than 1mA.

2. θJA is measured with the component mounted on an evaluation PC board in free air.

Thermal Resistance (Typical, Note 2) θJA (oC/W)

PDIP Package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Maximum Junction Temperature. . . . . . . . . . . . . . . . . . . . . . . 150oC

Maximum Storage Temperature Range . . . . . . . . . .-65oC to 150oC

Maximum Lead Temperature (Soldering, 10s) . . . . . . . . . . . . 300oC

Electrical Specifications Temperature = -40

o

C to 85oC, VDD = 2.5V to 5.5V, VSS = 0V, Unless Otherwise Specified. Typical

Specifications Measured at Temperature = 25oC and VDD = 2.8V, Unless Otherwise Specified

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

Operating Voltage, V
Operating Current, I

DD

DD

Note 1 2.5 - 5.5 V
All Inputs = VDD or GND, Note 2

= 2.8V - 1.0 10.0 µA

V

DD

VDD = 5.5V - 4.0 20.0 µA

INPUT CURRENT

C0 - C3, I
S/S, I

SS

DT, I

DT

IN

All Inputs VDD or GND
VDD = 2.8V
Note 3

0.0 - 1 µA

0.5 1.5 3.0 µA

40.0 - 110 µA

INPUT VOLTAGE

C0 - C3, DT, S/S

V

IL

V

IH

- - 0.3V

0.7V

DD

--V

DD

V

Segment Output Voltage

V

OL

V

OH

IOL = 1µA - - 0.8 V
IOH = 1µAV

- 0.8 - - V

DD

Backplane Output Voltage

V

OL

V

OH

IOL = 10µA - - 0.8 V
IOH = 10µAV

- 0.8 - - V

DD

OSCILLATOR STABILITY

Temperature = 25oC, VDD = 2.5V to 5.5V - 0.1 - ppm
Temperature = -40oC to 85oC, VDD = 2.5V to 5.5V - 5 - ppm

S/S PULSE WIDTH

High-Pass Filter (Modes 0 - 3), t
Debounce (Modes 4, 6, 8, 10), t

HP
DE

Without Debounce (Modes 5, 7, 9, 11), t

DE

5 - 10,000 µs

10,000 - - µs

5--µs

NOTES:

1. Internal reset to 00000 requires a maximum VDD rise time of 1µs. Longer rise times at power-up may cause improper reset.

2. Operating current is measured with the LCD disconnected, and input current ISS and IDT supplied externally.

3. Inputs C0 - C3 are latched internally and draw no DC current after switching. During switching, a 90µA peak current ma y be dra wn f or 10ns.

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