FAIRCHILD 74ACT818SPC

Revised September 2000
74ACT818
8-Bit Diagnostic Register
General Description
Features
The ACT818 is a high-speed, general-purpose pipeline
register with an on-board diagnostic register for performing
serial diagnostics and/or writable control store loading.
■ On-line and off-line system diagnostics
The D-to-Y path provides an 8-bit parallel data path pipeline register for normal system operation. The diagnostic
register can load parallel data to or from the pipeline register and can output data through the D input port (as in
WCS loading).
■ Diagnostic register and diagnostic testing
The 8-bit diagnostic register has multiplexer inputs that
select parallel inputs from the Y-port or adjacent bits in the
diagnostic register to operate as a right-shift-only register.
This register can then participate in a serial loop throughout
the system where normal data, address, status and control
registers are replaced with ACT818 diagnostic pipeline registers. The loop can be used to scan in a complete test routine starting point (Data, Address, etc.). Then after a
specified number of machine cycles it scans out the results
to be inspected for the expected results. WCS loading can
be accomplished using the same technique. An instruction
word can be serially shifted into the shadow register and
written into the WCS RAM by enabling the D output.
■ Outputs source/sink 24 mA
■ Swaps the contents of diagnostic register and output
register
■ Cascadable for wide control words as used in microprogramming
■ Edge-triggered D registers
■ ACT818 has TTL-compatible inputs
■ ACT818 is functionally- and pin-compatible to AMD
Am29818 and MMI 74S818
Applications
• Register for microprogram control store
• Status register
• Data register
• Instruction register
• Interrupt mask register
• Pipeline register
• General purpose register
• Parallel-serial/serial-parallel converter
Ordering Code:
Order Number
Order Package
74ACT818SPC
N24C
Package Description
24-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Logic Symbol
Connection Diagram
FACT is a trademark of Fairchild Semiconductor Corporation.
© 2000 Fairchild Semiconductor Corporation
DS009801
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74ACT818 8-Bit Diagnostic Register
July 1988
74ACT818
Pin Descriptions
Functional Description
Pin Names
Data transfers into the diagnostic register occur on the
LOW-to-HIGH transition of DCLK. Mode and SDI determine what data source will be loaded. The pipeline register
is loaded on the LOW-to-HIGH transition of PCLK. Mode
selects whether the data source is the data input or the
diagnostic register output. Because of the independence of
the clock inputs, data can be shifted in the diagnostic register via DCLK and loaded into the pipeline register from the
data input via PCLK simultaneously, as long as no setup or
hold times are violated. This simultaneous operation is
legal.
Description
D0–D7
Data Inputs
SDI
Serial Data Input
DCLK
Diagnostics Clock
MODE
Control Input
PCLK
Pipeline Register Clock
OEY
Output Enable Input
SDO
Serial Data Output
Y0–Y7
Data Outputs
Function Table
Inputs
SDI
X
Outputs
MODE DCLK PCLK
L
X
L
L
H
X
X
H
X
H
H
X
X
SDO
Diagnostic Reg.
Pipeline Reg.
S7
SI<SI − 1,
NA
Operation
Serial Shift; D7–D0 Disabled
SO<SDI
S7
NA
PI<DI
L
SI<YI
NA
Normal Load Pipeline Register
Load Diagnostic Register from Y;
SDI
NA
PI<SI
Load Pipeline Register from
X
H
Hold
NA
Hold Diagnostic Register; DI
DI Disabled
Diagnostic Register
Enabled
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
= LOW-to-HIGH Clock Transition
Diagnostic Register
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Block Diagram
2
Recommended Operating
Conditions
−0.5V to +7.0V
Supply Voltage (VCC)
DC Input Diode Current (IIK)
VI = −0.5V
−20 mA
VI = VCC +0.5V
+20 mA
DC Input Voltage (VI)
Supply Voltage (VCC)
0V to VCC
Output Voltage (VO)
−0.5V to VCC +0.5V
0V to VCC
−40°C to +85°C
Operating Temperature (TA)
Minimum Input Edge Rate (∆V/∆t)
DC Output Diode Current (IOK)
VO = −0.5V
−20 mA
VO = VCC + 0.5V
125 mV/ns
VIN from 0.8V to 2.0V
+20 mA
DC Output Voltage (VO)
4.5V to 5.5V
Input Voltage (VI)
VCC @ 4.5V, 5.5V
−0.5V to VCC + 0.5V
DC Output Source
± 50 mA
or Sink Current (IO)
DC VCC or Ground Current
± 50 mA
per Output Pin (I CC or IGND)
Storage Temperature (TSTG)
Note 1: Absolute maximum ratings are those values beyond which damage
to the device may occur. The databook specifications should be met, without exception, to ensure that the system design is reliable over its power
supply, temperature, and output/input loading variables. Fairchild does not
recommend operation of FACT circuits outside databook specifications.
−65°C to +150 °C
Junction Temperature (TJ)
140°C
PDIP
DC Electrical Characteristics
Symbol
Parameter
VCC
TA = +25°C
(V)
Typ
TA = −40°C to +85°C
Units
Minimum HIGH Level
4.5
1.5
2.0
2.0
Input Voltage
5.5
1.5
2.0
2.0
Maximum LOW Level
4.5
1.5
0.8
0.8
Input Voltage
5.5
1.5
0.8
0.8
IIN
Maximum Input Leakage Current
5.5
± 0.1
± 1.0
µA
IOZ
Maximum 3-STATE
5.5
± 0.5
± 5.0
µA
5.5
8.0
80.0
µA
1.5
mA
VIH
VIL
Leakage Current
ICC
Maximum Quiescent Supply Current
ICCT
Maximum Additional
ICC/Input
VOH
Conditions
Guaranteed Limits
5.5
V
V
VOUT = 0.1V
or VCC − 0.1V
VOUT = 0.1V
or VCC − 0.1V
VIN = VCC
OE = VIH
VOUT = 0V, VCC
VIN = VCC or GND
VIN = VCC − 2.1V
VCC = 5.5V
VIN = VIL or VIH
Minimum HIGH
Level Output Voltage,
4.5
3.86
3.76
V
IOH = −24 mA
Y0–Y7 Outputs
5.5
4.86
4.76
V
IOH =−24 mA (Note 2)
Level Output Voltage,
4.5
3.86
3.76
V
IOH = −8 mA
D0–D7, SDO Outputs
5.5
4.86
4.76
V
IOH = −8 mA
4.5
0.36
0.44
V
IOL = 24 mA
Minimum HIGH
VOL
Level Output Voltage,
IOLD
Y0–Y7 Outputs
5.5
0.36
0.44
V
IOL = 24 mA (Note 2)
Maximum LOW Level Output Voltage,
4.5
0.36
0.44
V
IOL = 8 mA
D0–D7, SDO Outputs
5.5
0.36
0.44
V
IOL = 8 mA
5.5
75
mA
VOLD = 1.65V Max
5.5
−75
mA
VOHD = 3.85V Min
5.5
32
mA
VOLD = 1.65V Max
5.5
−32
mA
VOHD = 3.85V Min
Minimum Dynamic Output Current
Y0–Y7 Outputs
IOHD
Minimum Dynamic Output Current
Y0–Y7 Outputs
IOLD
Minimum Dynamic Output Current
D0–D7, SDO Outputs (Note 3)
IOHD
VIN = VIL or VIH
Maximum LOW
Minimum Dynamic Output Current
D0–D7, SDO Outputs (Note 3)
Note 2: All outputs loaded; thresholds on input associated with output under test.
Note 3: Test load 50 pF, 500Ω to ground.
3
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74ACT818
Absolute Maximum Ratings(Note 1)
74ACT818
AC Electrical Characteristics
Symbol
tPHL
Parameter
Propagation Delay
PCLK to Y
tPLH
Propagation Delay
PCLK to Y
tPHL
Propagation Delay
MODE to SDO
tPLH
Propagation Delay
MODE to SDO
tPHL
Propagation Delay
SDI to SDO
tPLH
Propagation Delay
SDI to SDO
tPHL
Propagation Delay
DCLK to SDO
tPLH
Propagation Delay
DCLK to SDO
tPZL
Output Enable Time
OEY to Yn
tPLZ
Output Disable Time
OEY to Yn
tPZL
Output Enable Time
DCLK to Dn
tPLZ
Output Disable Time
DCLK to Dn
tPZH
Output Enable Time
OEY to Yn
tPHZ
Output Disable Time
OEY to Yn
tPZH
Output Enable Time
DCLK to Dn
tPHZ
Output Disable Time
DCLK to Dn
VCC
TA = +25°C
(V)
CL = 50 pF
CL = 50 pF
Units
(Note 4)
Min
Typ
Max
Min
Max
5.0
3.0
6.0
9.0
2.5
9.5
ns
5.0
3.0
6.5
9.0
2.5
10.0
ns
5.0
4.0
8.0
11.0
3.5
12.0
ns
5.0
4.0
8.0
11.5
4.0
12.5
ns
5.0
3.5
7.5
10.5
3.0
12.0
ns
5.0
3.5
7.5
10.5
3.5
12.0
ns
5.0
4.5
9.0
12.5
4.0
14.0
ns
5.0
4.5
9.5
13.0
4.0
14.5
ns
5.0
2.5
6.0
9.0
2.5
10.0
ns
5.0
1.5
5.5
8.0
1.0
9.0
ns
5.0
3.0
8.0
12.0
3.0
13.5
ns
5.0
2.0
8.5
11.0
1.5
12.0
ns
5.0
3.0
8.0
10.0
2.5
11.0
ns
5.0
2.5
9.0
11.0
2.0
11.5
ns
5.0
3.0
6.5
11.5
3.0
13.0
ns
5.0
3.0
7.5
12.0
2.0
13.0
ns
Note 4: Voltage Range 5.0 is 5.0V ± 0.5V.
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TA = −40°C to +85°C
4
Symbol
Parameter
Setup Time
tS
D to PCLK
Hold Time
tH
D to PCLK
tH
Setup Time
MODE to PCLK
tH
Hold Time
MODE to PCLK
Setup Time
tS
Y to DCLK
tS
Hold Time
Y to DCLK
Setup Time
tS
MODE to DCLK
Hold Time
tH
MODE to DCLK
tS
Setup Time
SDI to DCLK
tH
Hold Time
SDI to DCLK
Setup Time
tS
DCLK to PCLK
tS
Setup Time
PCLK to DCLK
Pulse Width
tW
PCLK HIGH or LOW
Pulse Width
tW
DCLK HIGH or LOW
VCC
TA = +25°C
(V)
CL = 50 pF
TA = −40°C to +85°C
CL = 50 pF
Units
(Note 5)
Typ
Guaranteed Minimum
5.0
1.0
4.0
5.0
ns
5.0
0.0
1.0
1.0
ns
5.0
2.5
4.5
5.5
ns
5.0
−1.0
0.0
0.0
ns
5.0
0.5
2.5
2.5
ns
5.0
0
1.0
1.5
ns
5.0
2.0
4.0
4.0
ns
5.0
−0.5
1.0
1.0
ns
5.0
2.0
3.5
4.5
ns
5.0
−0.5
1.0
1.0
ns
5.0
6.0
9.0
10.5
ns
5.0
6.0
11.0
11.5
ns
5.0
2.0
3.0
3.0
ns
5.0
2.0
3.0
3.0
ns
Note 5: Voltage range 5.0 is 5.0V ± 0.5V.
Capacitance
Typ
Units
CIN
Symbol
Input Capacitance
Parameter
4.5
pF
VCC = OPEN
CPD
Power Dissipation Capacitance
20
pF
VCC = 5.0V
5
Conditions
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74ACT818
AC Operating Requirements
74ACT818 8-Bit Diagnostic Register
Physical Dimensions inches (millimeters) unless otherwise noted
24-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Package Number N24C
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.
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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:
2. A critical component in any component of a life support
device or system whose failure to perform can be reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the
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to perform when properly used in accordance with
instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the
user.
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6