
AC Electrical Characteristics
T
A
= 40C to +85C, V
DD
= 5V
±
0.5V (Continued)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
Enable Input
Set-Up Time
Hold Time
Data Output
Clock Low to Data Out
Time
(Note 5)
t
ES
t
EH
100
100
ns
ns
t
CDO
C
L
= 50 pF
500
ns
Note 1:
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur.
Note 2:
Molded DIP Package, Board Mount,
θ
JA
= 52C/W, derate 19.2 mW/C above 25C.
Note 3:
Molded DIP Package, Socket Mount,
θ
JA
= 58C/W, derate 17.2 mW/C above 25C.
Note 4:
74LSTTL V
OH
= 2.7V
@
I
OUT
= 400 μA, TTL V
OH
= 2.4V
@
I
OUT
= 400 μA.
Note 5:
For timing purposes, the signals ENABLE and BLANK can be considered to be totally independent of each other.
Note 6:
AC input waveform specification for test purposes: t
r
, t
f
≤
20 ns, f = 800 kHz, 50%
±
10% duty cycle.
Note 7:
Clock input rise and fall times must not exceed 5 μs.
Connection Diagrams
Plastic Chip Carrier
00792508
Top View
Order Number MM58342V
See NS Package Number V28B
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 MM58342 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
MM58342 is shown in Figure 1
Figure 2 shows the pinout of the MM58342 device, where
output 1 (pin 12) is equivalent to bit 1 (i.e., 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
digit/segment/dot output.
A significant reduction in discrete board components can be
achieved by use of the MM58342, because external
Dual-In-Line Package
00792502
Top View
Order Number MM58342N
See NS Package Number N28B
FIGURE 2.
M
www.national.com
3