当前位置:文档之家› 74LVC245(电压逻辑隔离)

74LVC245(电压逻辑隔离)


Waveform : Refer to test circuit of switching characteristics.
2. duty cycle ≤ 50%
Conditions Data retention At operation T / R, OE Output "H" or "L" Output "Z" or VCC:OFF
Note: The absolute maximum ratings are values which must not individually be exceeded, and furthermore, no two of which may be realized at the same time.
4
HD74LVC245A
Switching Characteristics
Ta = –40 to 85°C
Item Propagation delay time
Symbol VCC (V)
t PLH
2.7
t PHL
3.3±0.3
5.0±0.5
Min Typ Max — — 8.0 1.5 — 7.0 — — 5.5
Test Circuit
VCC
VCC
OE Input Pulse Generator Zout = 50 Ω
T/R
See Function Table
S1 A0 B0
Output
500 Ω S2
CL =
450 Ω
50 pF 50 Ω Scope
OPEN *1 See under table GND
Note:
Function Table
Inputs
OE
T/R
L
L
L
H
H
X
H : High level L : Low level X : Immaterial Z : High impedance
Operation B data to A bus A data to B bus Z
HD74LVC245A
Pin Arrangement
tosLH = | tPLHm - tPLHn|, tosHL = | tPHLm - tPHLn|
Unit ns ns ns ns ns ns ns ns ns ns ns ns pF pF
From (Input) To (Output)
A or B
B or A
OE
A or B
OE
A or B
5
HD74LVC245A
Ta = –40 to 85°C
Symbol VCC (V) Min
Max Unit
VIH
2.7 to 3.6 2.0

V
4.5 to 5.5 VCC×0.7 —
V
VIL
2.7 to 3.6 —
0.8
V
4.5 to 5.5 —
VCC×0.3 V
VOH
2.7 to 5.5 VCC –0.2 —
V
2.7
4. Waveform – B shows input conditions such that the output is "H" level when enable by the output control.
7
6.50 6.80 Max
20
11
4.40
1
10
0.65
*0.22+–00..0078 0.20 ± 0.06
2.2

V
3.0
2.4

V
3.0
2.2

V
4.5
3.8

V
VOL
2.7 to 5.5 —
2.7

0.2
V
0.4
V
3.0

0.55 V
4.5

0.55 V
I IN
0 to 5.5 —
I OZ
2.7 to 5.5 —
±5.0 µA ±5.0 µA
Output leak current
I OFF
Quiescent supply current ICC
+0.03 –0.04
0.07
Hitachi Code JEDEC EIAJ Weight (reference value)
TTP-20DA — — 0.07 g
Cautions
1. Hitachi neither warrants nor grants licenses of any rights of Hitachi’s or any third party’s patent, copyright, trademark, or other intellectual property rights for information contained in this document. Hitachi bears no responsibility for problems that may arise with third party’s rights, including intellectual property rights, in connection with use of the information contained in this document.
GND
1. tr = 2.5 ns, tf = 2.5 ns 2. Input waveform : PRR = 10 MHz, duty cycle 50%
3. Waveform – A shows input conditions such that the output is "L" level when enable by the output control.
∆ I CC
0

2.7 to 3.6 —
2.7 to 5.5 —
3.0 to 3.6 —
20
µA
±10 µA
10
µA
500 µA
பைடு நூலகம்
Test Conditions
IOH = –100 µA IOH = –12 mA
IOH = –24 mA
IOL = 100 µA IOL = 12 mA IOL = 24 mA
10 %
tr
90 % Vref
tPLH
Vref
tf
90 % Vref
10 %
tPHL
Vref
VIH GND VOH VOL
6
HD74LVC245A
Waveforms – 2
tf
90 %
OE
Vref
10 %
Waveform - A
Waveform - B
tZL Vref
tZH Vref
tr 90 %
2.7
———
3.3±0.3 — — 1.0
5.0±0.5 — — 1.0
Input capacitance
CIN
2.7
— 3.0 —
Output capacitance
CO
2.7
— 15.0 —
Note: 1. This parameter is characterized but not tested.
HD74LVC245A
Octal Bidirectional Transceivers with 3-state Outputs
ADE-205-111B(Z) 3rd Edition
December 1996
Description
The HD74LVC245A has eight buffers with three state outputs in a 20 pin package. When (T / R) is high, data flows from the A inputs to the B outputs, and when (T / R) is low, data flows from the B inputs to the A outputs. A and B bus are separated by making enable input (OE) high level. Low voltage and high speed operation is suitable at the battery drive product (note type personal computer) and low power consumption extends the life of a battery for long time operation.
Output enable time
t ZH
2.7
— — 9.5
t ZL
3.3±0.3 1.5 — 8.5
5.0±0.5 — — 7.0
Output disable time
t ZH
2.7
— — 8.5
t LZ
3.3±0.3 1.5 — 7.5
5.0±0.5 — — 6.5
Between outut pins skew *1 tOSLH t OSHL
VI/O
–0.5 to VCC +0.5
V
–0.5 to 6.0
V
Output current
IO
±50
mA
VCC, GND current / pin
ICC or IGND
100
mA
相关主题