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Philips Semiconductors Product specification
74ABT651Octal transceiver/register, inverting (3-State)
FEA TURES
•Independent registers for A and B buses
•The 74ABT651 is the inverting version of the 74ABT652
•Multiplexed real-time and stored data
•3-State outputs
•Live insertion/extraction permitted.
•Power-up 3-State
•Power-up reset
•Output capability: +64mA/–32mA
•Latch-up protection exceeds 500mA per Jedec Std 17
•ESD protection exceeds 2000 V per MIL STD 883 Method 3015
and 200 V per Machine Model
QUICK REFERENCE DATA
SYMBOL PARAMETER
t
PLH
t
PHL
C
C
I
CCZ
IN
I/O
Propagation delay
CPBA to An or CPAB to Bn
Input capacitance VI = 0V or V
I/O capacitance Outputs disabled; VO = 0V or V
Total supply current Outputs disabled; VCC =5.5V 110 µA
DESCRIPTION
The 74ABT651 high-performance BiCMOS device combines low
static and dynamic power dissipation with high speed and high
output drive.
The 74ABT651 transceiver/register consists of bus transceiver
circuits with 3-State outputs, D-type flip-flops, and control circuitry
arranged for multiplexed transmission of data directly from the input
bus or the internal registers. Data on the A or B bus will be clocked
into the registers as the appropriate clock pin goes High. Output
Enable (OEAB, OEBA
bus management.
The following examples demonstrate the four fundamental
bus-management functions that can be performed with the
74ABT651.
The select pins determine whether data is stored or transferred
through the device in real time.
The output enable pins determine the direction of the data flow.
CONDITIONS
= 25°C; GND = 0V
T
amb
CL = 50pF; VCC = 5V
CC
) and Select (SAB, SBA) pins are provided for
TYPICAL UNIT
3.8
4.4
4 pF
CC
7 pF
ns
ORDERING INFORMATION
PACKAGES TEMPERATURE RANGE OUTSIDE NORTH AMERICA NORTH AMERICA DWG NUMBER
24-Pin Plastic DIP –40°C to +85°C 74ABT651 N 74ABT651 N SOT222-1
24-Pin plastic SO –40°C to +85°C 74ABT651 D 74ABT651 D SOT137-1
24-Pin Plastic SSOP Type II –40°C to +85°C 74ABT651 DB 74ABT651 DB SOT340-1
24-Pin Plastic TSSOP Type I –40°C to +85°C 74ABT651 PW 74ABT651PW DH SOT355-1
PIN CONFIGURA TION
1
CPAB
2
SAB
3
OEAB
4
A0
5
A1
6
A2
7
A3
8
A4
9
A5
10
A6
11
A7
12
GND
V
24
CC
CPBA
23
SBA
22
OEBA
21
B0
20
B1
19
B2
18
B3
17
B4
16
B5
15
B6
14
B713
SA00094
PIN DESCRIPTION
PIN
NUMBER
1, 23
2, 22
3, 21
4, 5, 6, 7, 8,
9, 10, 11
20, 19, 18,
17, 16, 15,
14, 13
12 GND Ground (0V)
24 V
SYMBOL FUNCTION
CPAB /
CPBA
SAB /
SBA
OEAB /
OEBA
A0 – A7 Data inputs/outputs (A side)
B0 – B7 Data inputs/outputs (B side)
CC
A to B clock input / B to A clock input
A to B select input / B to A select input
A to B Output Enable input /
B to A Output Enable input
(active–Low)
Positive supply voltage
1995 Sep 06 853-1783 15703
1
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Philips Semiconductors Product specification
74ABT651Octal transceiver/register, inverting (3-State)
LOGIC SYMBOL (IEEE/IEC)
21
3
23
22
1
2
4
5
6
7
8
9
10
11
EN1 [BA]
EN2 [AB]
C4
G5
C6
G7
1
1
6D 7
17
54D
5
1
1
2
LOGIC SYMBOL
4567 891011
A0 A1 A2 A3 A4 A5 A6 A7
23 CPBA
22 SBA
20
19
18
17
16
15
14
13
SA00125
SAB2
CPAB1
B0 B1 B2 B3 B4 B5 B6 B7
20 19 18 17 16 15 14 13
3OEAB
21OEBA
SA00095
REAL TIME BUS TRANSFER
BUS B TO BUS A
REAL TIME BUS TRANSFER
BUS A TO BUS B
STORAGE FROM
A, B, OR A AND B
TRANSFER STORED DATA
TO A OR B
ABABABAB
}
OEABOEBA
CPABCPBA SAB SBA
LLXXXL
OEABOEBA
HHXXLX
}
CPABCPBA SAB SBA
}
OEABOEBA
CPABCPBA SAB SBA
XH↑XXX
LXX↑XX
LH↑↑XX
}
OEABOEBA
CPABCPBA SAB SBA
H L H | L H | L H H
SA00097
1995 Sep 06
2
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Philips Semiconductors Product specification
74ABT651Octal transceiver/register, inverting (3-State)
FUNCTION TABLE
INPUTS DATA I/O
OEAB OEBA CPAB CPBA SAB SBA An Bn
L
L
X
H
L
L
L
L
H
H
H L H or L H or L H H Output Output
H = High voltage level
L = Low voltage level
X = Don’t care
↑ = Low-to-High clock transition
* The data output function may be enabled or disabled by various signals at the OEBA
enabled, i.e., data at the bus pins will be stored on every Low-to-High transition of the clock.
** If both Select controls (SAB and SBA) are Low, then clocks can occur simultaneously. If either Select control is High, the clocks must be
staggered in order to load both registers.
H
H
H
H
X
L
L
L
H
H
H or L
↑
↑
↑
H or L
↑
X
X
X
H or L
H or L
↑
H or L
↑
↑
↑
X
H or L
X
X
X
X
X
**
X
X
X
X
L
H
X
X
X
X
Input Input
Input
X**Unspecified
output*
L
H
X
X
Output Input
Input Output
Unspecified
output*
Input
Isolation
Store A and B data
Store A, Hold B
Store A in both registers
Hold A, Store B
Store B in both registers
Real time B data to A bus
Stored B
data to A bus
Real time A data to B bus
data to B bus
Store A
Stored A data to B bus
Stored B
data to A bus
and OEAB inputs. Data input functions are always
LOGIC DIAGRAM
OEBA
OEAB
CPBA
SBA
CPAB
SAB
A0
A1
A2
A3
A4
A5
A6
A7
21
3
23
22
1
2
1of 8 Channels
4
1D
C1
Q
5
6
7
8
9
10
11
DETAIL A X 7
1D
C1
Q
20
B0
19
B1
18
B2
17
B3
16
B4
15
B5
14
B6
13
B7
1995 Sep 06
SA00098
3