74FR2245SC [FAIRCHILD]
Octal Bidirectional Transceiver with 3-STATE Outputs; 八路双向收发器与3态输出
| 型号： | 74FR2245SC |
| 厂家： | 
FAIRCHILD SEMICONDUCTOR |
| 描述： | Octal Bidirectional Transceiver with 3-STATE Outputs |
| 文件： | 总5页 (文件大小：44K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
April 1995
Revised August 1999
74FR2245
Octal Bidirectional Transceiver with 3-STATE Outputs
General Description
Features
The 74FR2245 contains eight non-inverting bidirectional
buffers with 3-STATE outputs and is intended for bus-ori-
ented applications. Current sinking capability is 64 mA on
the A Port. The Transmit/Receive (T/R) input determines
the direction of data flow through the bidirectional trans-
ceiver. Transmit (active-HIGH) enables data from A Ports
to B Ports; Receive (active-LOW) enables data from B
Ports to A Ports. The Output Enable input, when HIGH, dis-
ables both A and B Ports by placing them in a High Z con-
dition.
■ Non-inverting buffers
■ Bidirectional data path
■ Guaranteed pin-to-pin skew
■ 25Ω series resistors in B outputs eliminate the need for
external resistors
■ 3-STATE outputs drive bus lines or buffer memory
address resistors
Ordering Code:
Order Number Package Number
Package Description
74FR2245SC
M20B
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Devices also available in Tape and Reel. Specify by appending the suffix letter “X” letter to the ordering code.
Logic Symbol
Connection Diagram
Truth Table
Pin Descriptions
Inputs
Output
Pin Names
Description
OE
L
T/R
L
OE
Output Enable Input (Active-LOW)
Transmit/Receive Input
Bus B Data to Bus A
Bus A Data to Bus B
High Z State
T/R
L
H
A0–A7
B0–B7
Side A Inputs or 3-STATE Outputs
Side B Inputs or 3-STATE Outputs
H
X
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
© 1999 Fairchild Semiconductor Corporation
DS012114
www.fairchildsemi.com
Logic Diagram
www.fairchildsemi.com
2
Absolute Maximum Ratings(Note 1)
Recommended Operating
Conditions
Storage Temperature
−65°C to +150°C
Ambient Temperature under Bias
Junction Temperature under Bias
VCC Pin Potential to Ground Pin
Input Voltage (Note 2)
−55°C to +125°C
−55°C to +150°C
−0.5V to +7.0V
Free Air Ambient Temperature
Supply Voltage
0°C to +70°C
+4.5V to +5.5V
−0.5V to +7.0V
Input Current (Note 2)
−30 mA to +5.0 mA
Voltage Applied to Output
in HIGH State (with VCC = 0V)
Standard Output
−0.5V to VCC
Note 1: Absolute maximum ratings are values beyond which the device
may be damaged or have its useful life impaired. Functional operation
under these conditions is not implied.
3-STATE Output
−0.5V to +5.5V
Current Applied to Output
in LOW State (Max)
Note 2: Either voltage limit or current limit is sufficient to protect inputs.
twice the rated IOL (mA)
4000V
ESD Last Passing Voltage (Min)
DC Electrical Characteristics
V
Symbol
Parameter
Input HIGH Voltage
Min
Typ
Max
Units
Conditions
CC
V
V
V
V
2.0
V
V
V
V
V
V
V
V
Recognized HIGH Signal
Recognized LOW Signal
IH
Input LOW Voltage
0.8
IL
Input Clamp Diode Voltage
Output HIGH Voltage
−1.2
Min
Min
Min
Max
Max
Max
I
I
I
I
I
I
= −18 mA
CD
OH
IN
2.4
2.0
= −3 mA (A , B )
n n
OH
OH
OL
OL
OL
= −15 mA (A , B )
n
n
V
Output LOW Voltage
0.5
= 1 mA (B )
n
OL
0.75
0.55
= 12 mA (B )
n
= 64 mA (A )
n
I
I
Input HIGH Current
5
µA
Max
IH
V
= 2.7V (OE, T/R)
= 7.0V (OE, T/R)
IN
IN
Input HIGH Current
Breakdown Test
BVI
7
µA
Max
V
I
Input HIGH Current
Breakdown Test (I/O)
BVIT
100
µA
Max
V
V
= 5.5V (A , B )
n n
IN
I
Input LOW Current
Input Leakage Test
−250
µA
Max
0.0
IL
= 0.5V (OE, T/R)
= 1.9 µA
IN
V
4.75
V
I
ID
ID
All Other Pins Grounded
= 150 mV
I
Output Circuit Leakage Current
3.75
µA
0.0
V
IOD
OD
All Other Pins Grounded
I
I
I
I
I
I
I
I
+ I
Output Leakage Current
Output Leakage Current
Output Short-Circuit Current
Output HIGH Leakage Current
Bus Drainage Test
25
−150
−225
50
µA
µA
Max
Max
Max
Max
0.0
V
V
V
V
V
= 2.7V (A , B )
n n
IH
IL
OZH
OUT
OUT
OUT
OUT
OUT
+ I
= 0.5V (A , B )
n n
OZL
−100
mA
µA
= 0.0V (A , B )
n n
OS
= V (A , B )
CEX
ZZ
CC
n
n
100
75
µA
= 5.25V (A , B )
n
n
Power Supply Current
Power Supply Current
Power Supply Current
55
75
55
mA
mA
mA
Max
Max
Max
All Outputs HIGH
All Outputs LOW
Outputs 3-STATE
CCH
CCL
CCZ
110
75
C
Input Capacitance
8.0
pF
pF
5.0
5.0
IN
OE, T/R
17.0
A , B
n n
3
www.fairchildsemi.com
AC Electrical Characteristics
T
= +25°C
T = 0°C to +70°C
A
A
V
= +5.0V
= 50 pF
Typ
V
= +5.0V
C = 50 pF
L
CC
CC
Symbol
Parameter
Units
C
L
Min
1.0
1.0
2.5
2.5
1.7
1.7
Max
4.4
4.4
7.5
7.5
6.5
6.5
Min
1.0
1.0
2.5
2.5
1.7
1.7
Max
t
Propagation Delay
A to B or B to A
n
4.4
4.4
7.5
7.5
6.5
6.5
PLH
ns
ns
ns
t
PHL
n
n
n
t
Output Enable Time
PZH
t
PZL
t
Output Disable Time
PHZ
t
PLZ
Extended AC Electrical Characteristics
Symbol
Parameter
T
= 0°C to +70°C
T
= 0°C to +70°C
Units
A
A
V
= +5.0V
= 50 pF
V
= +5.0V
CC
CC
C
C
= 250 pF
L
L
Eight Outputs Switching
(Note 3)
(Note 4)
Min
1.0
1.0
2.5
2.5
1.3
1.3
Max
7.0
Min
2.5
2.5
Max
10.0
10.0
t
Propagation Delay
to B or B to A
n
PLH
ns
ns
ns
ns
ns
ns
t
t
t
t
t
t
A
7.0
PHL
PZH
PZL
n
n
n
Output Enable Time
10.0
10.0
6.5
Output Disable Time
PHZ
PLZ
6.5
Pin-to-Pin Skew
for HL Transitions
Pin-to-Pin Skew
for LH Transitions
Pin-to-Pin Skew
for HL/LH Transitions
OSHL
1.7
1.0
3.3
(Note 5)
t
OSLH
(Note 5)
t
OST
(Note 5)
Note 3: This specification is guaranteed but not tested. The limits apply to propagation delays for all paths described switching in phase,
i.e., all LOW-to-HIGH, HIGH-to-LOW, 3-STATE-to-HIGH, etc.
Note 4: These specifications guaranteed but not tested. The limits represent propagation delays with 250 pF load capacitors in place of the 50 pF load
capacitors in the standard AC load. This specification pertains to single output switching only.
Note 5: Skew is defined as the absolute value of the difference between the actual propagation delays for any two outputs of the same device. The specifi-
cation applies to any outputs switching HIGH-to-LOW (t
teed with all outputs switching in phase.
), LOW-to-HIGH (t
), or HIGH-to-LOW and/or LOW-to-HIGH (t
). Specifications guaran-
OST
OSHL
OSLH
www.fairchildsemi.com
4
Physical Dimensions inches (millimeters) unless otherwise noted
20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
Package Number M20B
Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be rea-
sonably expected to result in a significant injury to the
user.
2. A critical component in any component of a life support
device or system whose failure to perform can be rea-
sonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
www.fairchildsemi.com
5
www.fairchildsemi.com
相关型号：
74FR244PC_NL
Bus Driver, FR/FASTR Series, 2-Func, 4-Bit, True Output, TTL, PDIP20, 0.300 INCH, LEAD FREE, PLASTIC, MS-001, DIP-20
FAIRCHILD
©2020 ICPDF网 联系我们和版权申明