Symbol

Parameter

Conditions

Min

Typ

Max

Units

Clock Input

(Notes 3 and 4)

Frequency

800

kHz

High Time

300

ns

Low Time

300

ns

Data Input

Set-Up Time

100

ns

Hold Time

100

ns

Enable Input

Set-Up Time

100

ns

Hold Time

100

ns

Data Output

CLOCK Low to Data Out

500

ns

Time

Note 2

For timing purposes the signals ENABLE and BLANK can be considered to be totally independent of each other

Note 3

Note 4

Clock input rise and fall times must not exceed 5 ms

Connection Diagrams

Dual-In-Line Package

TLF5600 – 2

Top View

FIGURE 2

Order Number MM58241N or MM58241V

See NS Package Number N40A or V44A

Plastic Chip Carrier

TLF5600 – 8

Top View

Functional Description

This product is specifically designed to drive multiplexed or

non-multiplexed high voltage alphanumeric or dot matrix

vacuum fluorescent (VF) displays Character generation is

done externally in the microprocessor with a serial data

path to the display driver The MM58421 uses three signals

DATA IN CLOCK and ENABLE where ENABLE acts as an

external load signal Display blanking can be achieved by

means of the BLANKING CONTROL input and a logic ‘1’

will turn off all sections of the display A block diagram of

the MM58241 is shown in

Figure 1

Figure 2 shows the pinout of the MM58241 device where

output 1 (pin 18) is equivalent to bit 1 ie the first bit of data

to be loaded into the shift register following ENABLE high A

logic ‘1’ at the input will turn on the corresponding display

digitsegmentdot output

A significant reduction in discrete board components can be

achieved by use of the MM58241 because external pull-

down resistors are not required Due to the nature of the

output stage both its on and off impedance values vary as a

function of the display voltage applied However

Figures 3a

and

3b show that this output impedance will remain con-

stant for a fixed value of display voltage

3