74avch1t45 NXP Semiconductors, 74avch1t45 Datasheet - Page 16

• Manufacturer Part Number: 74avch1t45
• Description: 74avch1t45 Dual Supply Translating Transceiver; 3-state
• Manufacturer: NXP Semiconductors

NXP Semiconductors
74AVCH1T45_1
Product data sheet
13.2 Bidirectional logic level-shifting application
Figure 9
application. Since the device does not have an output enable pin, the system designer
should take precautions to avoid bus contention between system-1 and system-2 when
changing directions.
Table 16
and then from system-2 to system-1.
Table 16.
[1]
State DIR CTRL I/O-1
1
2
3
4
Fig 9. Bidirectional logic level-shifting application
H = HIGH voltage level;
L = LOW voltage level;
Z = high-impedance OFF-state.
H
H
L
L
shows the 74AVCH1T45 being used in a bidirectional logic level-shifting
gives a sequence that will illustrate data transmission from system-1 to system-2
Description bidirectional logic level-shifting application
DIR CTRL
VCC1
I/O-1
system-1
output
Z
Z
input
Rev. 01 — 25 October 2007
VCC1
I/O-2
input
Z
Z
output
V
CC(A)
GND
A
1
2
3
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 bus hold.
DIR bit is set LOW. I/O-1 and I/O-2 still are disabled.
The bus-line state depends on bus hold.
system-2 data to system-1
74AVCH1T45
Dual supply translating transceiver; 3-state
6
5
4
V
DIR
B
CC(B)
74AVCH1T45
VCC2
[1]
system-2
VCC2
I/O-2
001aag890
© NXP B.V. 2007. All rights reserved.
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