74avc2t45 NXP Semiconductors, 74avc2t45 Datasheet - Page 22

• Manufacturer Part Number: 74avc2t45
• Description: 74avc2t45 Dual-bit, Dual-supply Voltage Level Translator/transceiver; 3-state
• Manufacturer: NXP Semiconductors

NXP Semiconductors
74AVC2T45_1
Product data sheet
Fig 9. Bidirectional logic level-shifting application
DIR CTRL
System-1 and system-2 must use the same conditions, i.e., both pull-up or both pull-down.
V
I/O-1
CC1
13.2 Bidirectional logic level-shifting application
system-1
PULL-UP/DOWN
Figure 9
application. Since the device does not have an output enable (OE) pin, the system
designer should take precautions to avoid bus contention between system-1 and
system-2 when changing directions.
Table 12
and then from system-2 to system-1.
Table 12.
[1]
[2]
State DIR CTRL I/O-1
1
2
3
4
System-1 and system-2 must use the same conditions, i.e., both pull-up or both pull-down.
H = HIGH voltage level;
L = LOW voltage level;
Z = high-impedance OFF-state.
H
H
L
L
shows the 74AVC2T45 being used in a bidirectional logic level-shifting
gives a sequence that will illustrate data transmission from system-1 to system-2
V
Bidirectional logic level-shifting application
CC1
V
CC(A)
GND
output
Z
Z
input
1A
2A
Dual-bit, dual-supply voltage level translator/transceiver; 3-state
1
2
3
4
Rev. 01 — 3 July 2007
74AVC2T45
I/O-2
input
Z
Z
output
Description
system-1 data to system-2
system-2 is getting ready to send data to system-1.
I/O-1 and I/O-2 are disabled. The bus-line state
depends on the pull-up or pull-down.
DIR bit is set LOW. I/O-1 and I/O-2 still are disabled.
The bus-line state depends on the pull-up or pull-down.
system-2 data to system-1
8
7
6
5
V
1B
2B
DIR
CC(B)
V
[1][2]
CC2
PULL-UP/DOWN
system-2
74AVC2T45
© NXP B.V. 2007. All rights reserved.
DIR CTRL
V
I/O-2
CC2
001aag582
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