MM58348N datasheet(3/6 Pages) NSC

3 / 6 page

Connection Diagrams

Dual-In-Line Package

TLF5601 – 2

Top View

FIGURE 2

Order Number MM58348N

See NS Package Number N40A

Plastic Chip Carrier

TLF5601 – 8

Top View

Order Number MM58348V

See NS Package Number V44A

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 MM58348 uses two signals

DATA IN and CLOCK with a format of a leading ‘‘1’’ fol-

lowed by the 35 data bits hence allowing data transfer with-

out an additional signal A block diagram of the MM58348 is

shown in

Figure 1

Figure 2 shows the pinout of the MM58348 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 the start

bit) 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 MM58348 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

Figure 3a

and

3b show that this output impedance will remain con-

stant for a fixed value of display voltage

TLF5601 – 3

FIGURE 3a Output Impedance Off

TLF5601 – 4

FIGURE 3b Output Impedance On

MM58348N Datasheet(PDF) 3 Page - National Semiconductor (TI)