WINGS WS74HC245

OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
WS74HC245
D
D
D
Wide Operating Voltage Range of 2 V to 6 V
High-Current 3-State Outputs Drive Bus
Lines Directly or Up To 15 LSTTL Loads
Low Power Consumption, 80-µA Max ICC
D
D
D
Typical tpd = 12 ns
±6-mA Output Drive at 5 V
Low Input Current of 1 µA Max
N, NS, PACKAGE
(TOP VIEW)
DIR
A1
A2
A3
A4
A5
A6
A7
A8
Vss
1
20
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
VDD
OE
B1
B2
B3
B4
B5
B6
B7
B8
description/ordering information
These octal bus transceivers are designed for asynchronous bi-direction communication between data buses.
The control-function implementation minimizes external timing requirements.
The devices allow data transmission from the A bus to the B bus or from the B bus to the A bus, depending on
the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to disable the
device so that the buses are effectively isolated.
ORDERING INFORMATION
PACKAGE†
TA
85°C
C
–40°C
–40
C to 85
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING
PDIP – N
Tube of 20
WS74HC245N
WS74HC245N
SOP – NS
Reel of 2000
WS74HC245NSR
HC245
HC245
1
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
WS74HC245
FUNCTION TABLE
INPUTS
OE
DIR
OPERATION
L
L
B data to A bus
L
H
A data to B bus
H
X
Isolation
logic diagram (positive logic)
DIR
1
19
A1
OE
2
18
B1
To Seven Other Channels
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V
Input clamp current, IIK (VI < 0 or VI > VDD) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±20 mA
Continuous output current, IO (VO = 0 to VDD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±35 mA
Continuous current through VDD or Vss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±70 mA
Package thermal impedance, θJA (see Note 2):
N package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69°C/W
NS package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60°C/W
.................................
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. The input and output voltage ratings may be exceeded if the input and output current ratings are observed.
2. The package thermal impedance is calculated in accordance with JESD 51-7.
2
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
WS74HC245
recommended operating conditions (see Note 3)
WS74HC245
VDD
VIH
Supply voltage
VDD = 2 V
VDD = 4.5 V
High-level input voltage
VI
VO
∆t/∆v
t/ v
Low-level input voltage
NOM
MAX
2
5
6
V
V
3.15
4.2
0.5
VDD = 4.5 V
VDD = 6 V
1.35
V
1.8
Input voltage
0
Output voltage
0
VDD = 2 V
VDD = 4.5 V
Input transition rise/fall time
UNIT
1.5
VDD = 6 V
VDD = 2 V
VIL
MIN
VDD
VDD
V
V
1000
500
VDD = 6 V
TA
Operating free-air temperature
NOTE 3: All unused inputs of the device must be held at VDD or Vss to ensure proper device operation.
ns
400
–40
85
°C
DC ELECTRICAL CHARACTERISTICS
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VOH
TEST CONDITIONS
ICC
Ci
A or B
MAX
UNIT
1.9
1.998
1.9
4.4
4.499
4.4
6V
5.9
5.999
5.9
IOH = –6 mA
IOH = –7.8 mA
4.5 V
3.98
4.3
3.84
6V
5.48
5.8
5.34
2V
0.002
0.1
0.1
IOL = 20 µA
A
4.5 V
0.001
0.1
0.1
6V
0.001
0.1
0.1
4.5 V
0.17
0.26
0.33
6V
0.15
0.26
0.33
6V
±0.1
±100
±1000
nA
6V
±0.01
±0.5
±5
µA
8
80
µA
10
10
pF
VI = VDD or 0
VO = VDD or 0
VI = VDD or 0,
WS74HC245
MIN
2V
VI = VIH or VIL
DIR or OE
TA = 25°C
TYP
MAX
4.5 V
IOL = 6 mA
IOL = 7.8 mA
II
IOZ
MIN
IOH = –20 µA
A
VI = VIH or VIL
VOL
VDD
C
IO = 0
DIR or OE
6V
2 V to 6 V
3
V
V
AC ELECTRICAL CHARACTERISTICS
3
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
WS74HC245
switching characteristics over recommended operating free-air temperature range, CL = 50 pF
(unless otherwise noted) (see Figure 1)
TA = 25°C
TYP
MAX
WS74HC245
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VDD
2V
40
105
130
tpd
A or B
B or A
4.5 V
15
21
26
6V
12
18
22
ten
OE
tdis
OE
tt
A or B
A or B
A or B
MIN
MIN
MAX
2V
125
230
290
4.5 V
23
46
58
6V
20
39
49
2V
74
200
250
4.5 V
25
40
50
6V
21
34
43
2V
20
60
75
4.5 V
8
12
15
6V
6
10
13
UNIT
ns
ns
ns
ns
switching characteristics over recommended operating free-air temperature range, CL = 150 pF
(unless otherwise noted) (see Figure 1)
TA = 25°C
MIN
TYP
MAX
WS74HC245
PARAMETER
FROM
(INPUT)
TO
(OUTPUT)
VDD
2V
54
135
170
tpd
A or B
B or A
4.5 V
18
27
34
ten
tt
OE
A or B
A or B
MIN
MAX
6V
15
23
29
2V
150
270
335
4.5 V
31
54
67
6V
25
46
56
2V
45
210
265
4.5 V
17
42
53
6V
13
36
45
UNIT
ns
ns
ns
operating characteristics, TA = 25°C
PARAMETER
Cpd
4
Power dissipation capacitance per transceiver
TEST CONDITIONS
No load
TYP
40
UNIT
pF
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
WS74HC245
PARAMETER MEASUREMENT INFORMATION
VCC
PARAMETER
Test
Point
From Output
Under Test
tPZH
S1
ten
RL
CL
(see Note A)
1 kΩ
tPZL
tPHZ
tdis
S2
RL
tPLZ
tpd or tt
1 kΩ
––
LOAD CIRCUIT
CL
S1
S2
50 pF
or
150 pF
Open
Closed
Closed
Open
Open
Closed
Closed
Open
Open
Open
50 pF
50 pF
or
150 pF
VDD
Input
50%
50%
0V
tPLH
In-Phase
Output
50%
10%
tPHL
90%
VOH
50%
10% V
OL
tf
90%
tr
tPHL
Out-of-Phase
Output
90%
tPLH
50%
10%
50%
10%
90%
VOH
VOL
tf
tr
VOLTAGE WAVEFORMS
PROPAGATION DELAY AND OUTPUT TRANSITION TIMES
Output
Control
(Low-Level
Enabling)
VDD
50%
50%
0V
tPZL
Output
Waveform 1
(See Note B)
tPLZ
10%
tPZH
Input
50%
10%
90%
90%
tr
VDD
50%
10% 0 V
Output
Waveform 2
(See Note B)
≈VDD
≈VCC
50%
VOL
tPHZ
50%
90%
VOH
≈0 V
tf
VOLTAGE WAVEFORM
INPUT RISE AND FALL TIMES
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES FOR 3-STATE OUTPUTS
NOTES: A. CL includes probe and test-fixture capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. Phase relationships between waveforms were chosen arbitrarily. All input pulses are supplied by generators having the following
characteristics: PRR ≤ 1 MHz, ZO = 50 Ω, tr = 6 ns, tf = 6 ns.
D. The outputs are measured one at a time with one input transition per measurement.
E. tPLZ and tPHZ are the same as tdis.
F. tPZL and tPZH are the same as ten.
G. tPLH and tPHL are the same as tpd.
Figure 1. Load Circuit and Voltage Waveforms
5
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
WS74HC245
PIN DESCRIPTION
PIN NO.
SYMBOL
1
2, 3, 4, 5, 6, 7, 8, 9
10
18, 17, 16, 15, 14, 13, 12, 11
19
20
DIR
A1 – A8
VSS
B1 – B8
OE
VDD
Direction control
Data inputs / Outputs
Ground (0V)
Data inputs / Outputs
Output enable input (active Low)
Positive power supply
PAD DIAGRAM
B7
VSS
B8
A8
A7
B6
A6
B5
WS74 HC245
Die Size = 69 mil x 72 mil
A5
Pad size = 90 um x 90 um
B4
A4
B3
A3
B2
B1
OE
VDD
DIR
A1
A2
The Coordinate of Low Left Corner for Each Pad
B2 (-741.9, -722.4)
A3 ( 651.8, -503.2)
B8 (-267.8, 657.6)
B1 (-558.3, -747.1)
A4 ( 651.8, -124.2)
B7 (-466.6, 657.6)
OE (-288.0, -747.1)
A5 ( 651.8, 74.6)
B6 (-741.9, 506.6)
VDD(-111.4, -742.5)
A6 ( 651.8, 454.0)
B5 (-741.9, 236.8)
DIR ( 85.8, -747.1)
A7 ( 559.5, 657.6)
B4 (-741.9, -143.4)
A1 ( 262.6, -747.1)
A8 ( 179.3, 657.6)
B3 (-741.9, -342.2)
A2 ( 642.8, -747.1)
VSS ( 2.7, 658.6)
6
WS74HC245
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS
7
WS74HC245
8
OCTAL BUS TRANSCEIVERS
WITH 3-STATE OUTPUTS