Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

please contact the National Semiconductor Sales Office/

Distributors for availability and specifications.

Voltage at Any Pin

V

Operating Temperature

−40˚C to +85˚C

Storage Temperature

−65˚C to +150˚C

Power Dissipation

300 mW at +85˚C

350 mW at +25˚C

Junction Temperature

+150˚C

Lead Temperature

(Soldering, 10 seconds)

300˚C

DC Electrical Characteristics

T

Parameter

Conditions

Min

Typ

Max

Units

Power Supply

3.0

10

V

Average Supply Current, I

DD

All Outputs Bits = Open, Data Out = Open,

BP_Out = Open, Clock In = 0V,

Data In = 0V, Data Load = 0V,

Osc In = 0V, BP_In = 32Hz

V

1.5

2.5

µA

V

10

µA

V

40

µA

Input Voltage Levels

Logic “0”

Logic “1”

Logic “0”

Logic “1”

Load, Clock, Data

V

V

V

V

2.4

2.0

0.9

0.4

V

V

V

V

Output Current Levels

Segments and Data Out

Sink

Source

V

V

20

20

µA

µA

BP Out Sink

BP Out Source

V

V

320

320

µA

µA

AC Electrical Characteristics

V

DD

≥ 4.7V, V

Symbol

Parameter

Min

Typ

Max

Units

f

C

Clock Frequency, V

500

kHz

t

CH

Clock Period High

(Notes 2, 3)

500

ns

t

CL

Clock Period Low

500

ns

t

DS

Data Set-Up before Clock

300

ns

t

DH

Data Hold Time after Clock

100

ns

t

LW

Minimum Load Pulse Width

500

ns

t

LTC

Load to Clock

400

ns

t

CDO

Clock to Data Valid

400

750

ns

Note 1: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the devices

should be operated at these limits. The table of “Electrical Characteristics” specifies conditions of device operation.

Note 3: Clock input rise and fall times must not excced 300 ms.

Functional Description

A block diagram for the MM5483 is shown in Figure 1 and a

package pinout is shown in Figure 2. Figure 3 shows a

possible 3-wire connection system with a typical signal for-

mat for Figure 3. Shown in Figure 4, the load input is an

asynchronous input and lets data through from the shift

register to the output buffers any time it is high. The load

input can be connected to V

Figure 5. In the 2-wire control mode, 31 bits (or less depend-

ing on the number of segments used) of data are clocked

into the MM5483 in a short time frame (with less than 0.1

second there probably will be no noticeable flicker) with no

more clocks until new information is to be displayed. If data

was slowly clocked in, it can be seen to “walk” across the

display in the 2-wire mode. An AC timing diagram can be

seen in Figure 6. It should be noted that data out is not a

TTL-compatible output.

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