MC74LVX4245 Datasheet, PDF (6/9 Pages) Motorola, Inc – LOW-VOLTAGE CMOS

MC74LVX4245
before VCCA). With a 7V/µs rate, the setup time was about
140ns. When all is said and done, the safest power–up
strategy is to simply power VCCA before VCCB. One more
note: if the VCCB ramp rate is faster than the VCCA ramp rate
then power problems might still occur, even if the VCCA
power–up began prior to the VCCB power–up.
MICROCHANNEL/
EISA/ISA/AT
5V
5V BUS
LOCAL
3V BUS
KEYBOARD
CONTROLLER
SUPER
I/O
CORE
LOGIC
TRANSCEIVERS
5V
VCCA
3V
VCCB
A PORT
A0:7
LVX4245
B PORT
B0:7
PCMCIA
CONTROLLER
VGA
CONTROLLER
3V
CACHE
SRAM
CPU
386/486
ROM
BIOS
MEMORY
DRIVER
Figure 4. MC74LVX4245 Fits Into a System with 3V Subsystem and 5V Subsystem
VCCA
(T/R) DIR
A0
A1
A2
A3
A4
A5
A6
A7
GND
GND
MC74LVX4245
STANDARD
74 SERIES
‘245
VCCB
VCCB
OE
B0
B1
B2
B3
B4
B5
B6
B7
GND
Figure 5. MC74LVX4245 Pin Arrangement Is Compatible to 20–Pin 74 Series ‘245s
MOTOROLA
6
LVX Data — Low–Voltage CMOS Logic
BR1492 — Rev 0