INTEGRATED CIRCUITS
74ABT16899
74ABTH16899
18-bit latched transceiver with 16-bit
parity generator/checker (3-State)
Product specification
Supersedes data of 1997 Mar 28
IC23 Data Handbook
1998 Feb 25
Philips
Semiconductors
Philips Semiconductors
Product specification
18-bit latched transceiver with 16-bit
parity generator/checker (3-State)
74ABT16899
74ABTH16899
FEATURES
•
Symmetrical (A and B bus functions are identical)
•
Selectable generate parity or ”feed-through” parity for A-to-B and
B-to-A directions
Parity error checking of the A and B bus latches is continuously
provided with ERRA and ERRB, even with both buses in 3-State.
The 74ABT/H16899 features independent latch enables for the A
and B bus latches, a select pin for ODD/EVEN parity, and separate
error signal output pins for checking parity.
•
Independent transparent latches for A-to-B and B-to-A directions
•
Selectable ODD/EVEN parity
•
Continuously checks parity of both A bus and B bus latches as
ERRA and ERRB
FUNCTIONAL DESCRIPTION
The 74ABT/H16899 has three principal modes of operation which
are outlined below. All modes apply to both the A-to-B and B-to-A
directions.
Transparent latch, Generate parity, Check A and B bus parity:
Bus A (B) communicates to Bus B (A), parity is generated and
passed on to the B (A) Bus as BPAR (APAR). If LEA and LEB are
High and the Mode Select (SEL) is Low, the parity generated from
A0-A7 and B0-B7 can be checked and monitored by ERRA and
ERRB. (Fault detection on both input and output buses.)
Transparent latch, Feed-through parity, Check A and B bus
parity:
Bus A (B) communicates to Bus B (A) in a feed-through mode if SEL
is High. Parity is still generated and checked as ERRA and ERRB
and can be used as an interrupt to signal a data/parity bit error to the
CPU.
Latched input, Generate/Feed-through parity, Check A (and B)
bus parity:
Independent latch enables (LEA and LEB) allow other permutations
of:
•
Open-collector ERR output
•
Ability to simultaneously generate and check parity
•
Can simultaneously read/latch A and B bus data
•
Output capability: +64 mA/–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
•
Power up 3-State
•
Power-up reset
•
Live insertion/extraction permitted
•
Bus-hold data inputs eliminate the need for external pull-up
resistors to hold unused inputs
DESCRIPTION
The 74ABT/H16899 is a 16-bit to 16-bit parity transceiver with
separate transparent latches for the A bus and B bus. Either bus
can generate or check parity. The parity bit can be fed-through with
no change or the generated parity can be substituted with the SEL
input.
•
Transparent latch / 1 bus latched / both buses latched
•
Feed-through parity / generate parity
•
Check in bus parity / check out bus parity / check in and out bus
parity
QUICK REFERENCE DATA
SYMBOL
t
PLH
t
PHL
t
PLH
t
PHL
C
IN
C
I/O
I
CCZ
I
CCL
Propagation delay
An to Bn or Bn to An
Propagation delay
An to ERRA
Input capacitance
Output capacitance
Quiescent supply current
PARAMETER
CONDITIONS
T
amb
= 25°C; GND = 0V
C
L
= 50pF; V
CC
= 5V
C
L
= 50pF; V
CC
= 5V
V
I
= 0V or V
CC
Outputs disabled; V
O
= 0V or V
CC
Outputs disabled; V
CC
=5.5V
Output Low; V
CC
= 5.5V
TYPICAL
2.7
5.0
4
7
500
10.5
UNIT
ns
ns
pF
pF
µA
mA
ORDERING INFORMATION
PACKAGES
56-Pin Plastic SSOP Type III
56-Pin Plastic TSSOP Type II
56-Pin Plastic SSOP Type III
56-Pin Plastic TSSOP Type II
TEMPERATURE RANGE
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
OUTSIDE NORTH AMERICA
74ABT16899 DL
74ABT16899 DGG
74ABTH16899 DL
74ABTH16899 DGG
NORTH AMERICA
BT16899 DL
BT16899 DGG
BH16899 DL
BH16899 DGG
DWG NUMBER
SOT371-1
SOT364-1
SOT371-1
SOT364-1
1998 Feb 25
2
853-1960 19018
Philips Semiconductors
Product specification
18-bit latched transceiver with 16-bit
parity generator/checker (3-State)
74ABT16899
74ABTH16899
PIN CONFIGURATION
ODD/EVEN
OEA
1A0
GND
1A1
1A2
1A3
1A4
V
CC
1A5
1A6
1A7
1APAR
1ERRA
GND
2ERRA
2APAR
2A7
2A6
2A5
V
CC
2A4
2A3
2A2
2A1
GND
2A0
LEB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
SEL
LEA
1B0
GND
1B1
1B2
1B3
1B4
V
CC
1B5
1B6
1B7
1BPAR
1ERRB
GND
2ERRB
2BPAR
2B7
2B6
2B5
V
CC
2B4
2B3
2B2
2B1
GND
2B0
OEB
SH00082
PIN DESCRIPTION
SYMBOL
1A0 - 1A7
2A0 - 2A7
1B0 - 1B7
2B0 - 2B7
1APAR
2APAR
1BPAR
2BPAR
ODD/EVEN
OEA, OEB
SEL
LEA, LEB
1ERRA, 1ERRB
2ERRA, 2ERRB
GND
V
CC
PIN
NUMBER
3, 5, 6, 7, 8, 10, 11, 12
27, 25, 24, 23, 22, 20, 19, 18
54, 52, 51, 50, 49, 47, 46, 45
30, 32, 33, 34, 35, 37, 38, 39
13, 17
44, 40
1
2, 29
56
55, 28
14, 43,
16, 41
4, 15, 26, 31, 42, 53
9, 21, 36, 48
NAME AND FUNCTION
Latched A bus 3-State inputs/outputs
Latched B bus 3-State inputs/outputs
A bus parity 3-State input
B bus parity 3-State input
Parity select input (Low for EVEN parity)
Output enable inputs (gate A to B,
B to A)
Mode select input (Low for generate)
Latch enable inputs (transparent High)
Error signal outputs (active-Low)
Ground (0V)
Positive supply voltage
1998 Feb 25
3
Philips Semiconductors
Product specification
18-bit latched transceiver with 16-bit
parity generator/checker (3-State)
74ABT16899
74ABTH16899
LOGIC SYMBOL
3
5
6
7
8
10
11
12
13
27
25
24
23
22
20
19
18
17
1A0 1A1 1A2 1A3 1A4 1A5 1A6 1A7 1APAR
55
28
56
1
2
29
LEA
LEB
SEL
ODD/EVEN
OEA
OEB
1B0 1B1 1B2 1B3 1B4 1B5 1B6 1B7 1BPAR
1ERRA
1ERRB
14
43
55
28
56
1
2
29
2A0 2A1 2A2 2A3 2A4 2A5 2A6 2A7 2APAR
LEA
LEB
SEL
ODD/EVEN
OEA
OEB
2B0 2B1 2B2 2B3 2B4 2B5 2B6 2B7 2BPAR
2ERRA
2ERRB
16
41
54
52
51
50
49
47
46
45
44
30
32
33
34
35
37
38
39
40
SH00083
PARITY AND ERROR FUNCTION TABLE
INPUTS
SEL
H
H
H
H
L
L
L
L
H
L
t
r
*
ODD/EVEN
H
H
L
L
H
H
L
L
xPAR
(A or B)
H
L
H
L
H
L
H
L
Σ
of High
Inputs
Even
Odd
Even
Odd
Even
Odd
Even
Odd
Even
Odd
Even
Odd
Even
Odd
Even
Odd
xPAR
(B or A)
H
H
L
L
H
H
L
L
H
L
H
L
L
H
L
H
OUTPUTS
ERRt
H
L
L
H
L
H
H
L
H
L
L
H
L
H
H
L
ERRr*
H
L
L
H
L
H
H
L
H
H
H
H
H
H
H
H
PARITY MODES
Odd
Mode
Feed-through/check parity
Even
Mode
Odd
Mode
Generate parity
Even
Mode
= High voltage level
= Low voltage level
= Transmit–if the data path is from A→B then ERRt is ERRA
= Receive–if the data path is from A→B then ERRr is ERRB
Blocked if latch is not transparent
1998 Feb 25
4
Philips Semiconductors
Product specification
18-bit latched transceiver with 16-bit
parity generator/checker (3-State)
74ABT16899
74ABTH16899
BLOCK DIAGRAM
OE
9–bit
Transparent
Latch
OEB
9–bit
Output
Buffer
LEA
A0
A1
A2
A3
A4
A5
A6
A7
APAR
LE
Parity
Generator
1
mux
0
B0
B1
B2
B3
B4
B5
B6
B7
BPAR
9–bit
Transparent
Latch
9–bit
Output
Buffer
OEA
OE
1
mux
0
Parity
Generator
LE
LEB
ERRA
SEL
ERRB
ODD/
EVEN
(1 of 2 parity blocks)
SH00084
FUNCTION TABLE
INPUTS
OEB
H
H
H
H
H
H
L
L
L
L
L
L
OEA
H
L
L
L
L
L
H
H
H
H
H
L
SEL
X
L
L
L
H
H
L
L
L
H
H
X
LEA
X
L
H
X
X
H
H
H
L
H
H
X
LEB
X
H
H
L
H
H
X
H
X
L
H
X
3-State A bus and B bus (input A & B simultaneously)
B
→
A, transparent B latch, generate parity from B0 - B7, check B bus parity
B
→
A, transparent A & B latch, generate parity from B0 - B7, check A & B bus parity
B
→
A, B bus latched, generate parity from latched B0 - B7 data, check B bus parity
B
→
A, transparent B latch, parity feed-through, check B bus parity
B
→
A, transparent A & B latch, parity feed-through, check A & B bus parity
A
→
B, transparent A latch, generate parity from A0 - A7, check A bus parity
A
→
B, transparent A & B latch, generate parity from A0 - A7, check A & B bus parity
A
→
B, A bus latched, generate parity from latched A0 - A7 data, check A bus parity
A
→
B, transparent A latch, parity feed-through, check A bus parity
A
→
B, transparent A & B latch, parity feed-through, check A & B bus parity
Output to A bus and B bus (NOT ALLOWED)
OPERATING MODE
H = High voltage level
L = Low voltage level
X = Don’t care
1998 Feb 25
5
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