1
IDTQS74FCT2821AT/BT/CT
HIGH-SPEED CMOS BUS INTERFACE 10-BIT REGISTER
INDUSTRIAL TEMPERATURE RANGE
MARCH 2002
2002 Integrated Device Technology, Inc.
DSC-5256/4
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IDTQS74FCT2821AT/BT/CT
INDUSTRIAL TEMPERATURE RANGE
HIGH-SPEED CMOS
BUS INTERFACE
10-BIT REGISTER
DESCRIPTION:
The IDTQS74FCT2821T is a 10-bit high-speed CMOS TTL-compatible
buffered register with 3-state outputs, with a 25
resister that is useful for
driving transmission lines and reducing system noise. The 2821 series parts
can replace the 821 series to reduce noise in an existing design. All inputs
have clamp diodes for undershoot noise suppression. All outputs have
ground bounce suppression. Outputs will not load an active bus when Vcc
is removed from the device.
FUNCTIONAL BLOCK DIAGRAM
OE
CP
D
Q
CP
Dx
Yx
25
FEATURES:
CMOS power levels: <7.5mW static
Undershoot clamp diodes on all outputs
True TTL input and output compatibility
Ground bounce controlled outputs
Reduced output swing of 0 to 3.5V
Built-in 25
series resistor outputs reduce reflection and other
system noise
A, B, and C speed grades
I
OL
= 12mA
Available in SOIC and QSOP packages
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INDUSTRIAL TEMPERATURE RANGE
IDTQS74FCT2821AT/BT/CT
HIGH-SPEED CMOS BUS INTERFACE 10-BIT REGISTER
SOIC/ QSOP
TOP VIEW
2
3
1
V
CC
20
19
18
15
16
23
22
24
21
17
Y
2
Y
4
Y
3
Y
6
Y
5
Y
1
Y
7
Y
8
13
14
CP
Y
9
Y
0
D
4
D
5
D
3
D
7
D
6
D
1
D
2
D
8
9
10
5
6
7
4
8
11
12
GND
OE
D
0
D
9
PIN CONFIGURATION
Symbol
Description
Max
Unit
V
TERM
Terminal Voltage with Respect to GND
0.5 to +7
V
T
STG
Storage Temperature
65 to +150
C
I
OUT
DC Output Current Max Sink Current/Pin
120
mA
I
IK
Input Diode Current, V
IN
< 0
20
mA
I
OK
Output Diode Current, V
OUT
< 0
50
mA
ABSOLUTE MAXIMUM RATINGS
(1)
NOTE:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause
permanent damage to the device. This is a stress rating only and functional operation
of the device at these or any other conditions above those indicated in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect reliability.
CAPACITANCE
(T
A
= +25C, F = 1.0MHz)
NOTES:
1. This parameter is measured at characterization but not tested.
2. Pins 1, 3-11, 13.
3. Pin 2.
4. Pins 15-22.
5. Pins 14, 23.
PIN DESCRIPTION
Pin Names
I/O
Description
Dx
I
D Flip-Flop Data Inputs
C P
I
Clock Pulse for the register. Enters data into the register
on the LOW-to-HIGH transition.
Y x
O
Register 3-State Outputs
OE
I
Output Control. When the OE input is HIGH, the Yx
outputs are in the high impedance state. When the OE
input is LOW, the TRUE register data is present at the
Yx outputs.
Symbol
Parameter
(1)
Conditions
Typ.
Max.
Unit
C
IN
(2)
Input Capacitance
V
IN
= 0V
4
--
pF
C
IN
(3)
Input Capacitance
V
IN
= 0V
8
--
pF
C
OUT
(4)
Output Capacitance
V
OUT
= 0V
6
--
pF
C
OUT
(5)
Output Capacitance
V
OUT
= 0V
8
--
pF
FUNCTION TABLE
(1)
Inputs
Internal
Outputs
OE
Dx
CP
Value Qx
Yx
Function
H
L
L
Z
High-Z
H
H
H
Z
High-Z
H
L
L
Z
Load
H
H
H
Z
Load
L
L
L
L
Load
L
H
H
H
Load
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
Z = High-Impedance
= LOW-to-HIGH transition
LOGIC SYMBOL
Dx
CP
OE
D
Q
Yx
CP
10
10
3
IDTQS74FCT2821AT/BT/CT
HIGH-SPEED CMOS BUS INTERFACE 10-BIT REGISTER
INDUSTRIAL TEMPERATURE RANGE
Symbol
Parameter
Test Conditions
Min.
Typ.
(1)
Max.
Unit
V
IH
Input HIGH Level
Guaranteed Logic HIGH Level
2
--
--
V
V
IL
Input LOW Level
Guaranteed Logic LOW Level
--
--
0.8
V
V
T
Input Hysteresis
V
TLH
- V
THL
for all inputs
--
0.2
--
V
I
IH
Input HIGH Current
V
CC
= Max.
0
V
IN
V
CC
--
--
5
A
I
IL
Input LOW Current
I
OZ
Off-State Output Current (Hi-Z)
V
CC
= Max
0
V
IN
V
CC
--
--
5
A
I
OR
Current Drive
V
CC
= Max., V
OUT
= 2.0V
(2)
50
--
--
mA
V
IC
Input Clamp Voltage
V
CC
= Min, I
IN
= -18mA , T
A
= 25C
(2)
--
0.7
1.2
V
V
OH
Output HIGH Voltage
V
CC
= Min.
I
OH
= -15mA
2.4
--
--
V
V
OL
Output LOW Voltage
V
CC
= Min.
I
OL
= 12mA
--
--
0.5
V
R
OUT
(3)
Output Resistance
V
CC
= Min.
I
OH
= 12mA
18
25
40
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= 40C to +85C, V
CC
= 5.0V 5%
NOTES:
1. Typical values are at V
CC
= 5.0V, T
A
= 25C.
2. This parameter is measured at characterization but not tested.
3. R
OUT
changed on March 8, 2002. See rear page for more information.
POWER SUPPLY CHARACTERISTICS
Following Conditions Apply Unless Otherwise Specified:
Industrial: T
A
= -40C to +85C, V
CC
= 5.0V 5%
Symbol
Parameter
Test Conditions
(1)
Min.
Max.
Unit
I
CC
Quiescent Power Supply Current
V
CC
= Max.
--
1.5
mA
freq = 0
0V
V
IN
0.2V or
V
CC
- 0.2V
V
IN
Vcc
I
CC
Supply Current per Input TTL Inputs HIGH
V
CC
= Max.
--
2
mA
V
IN
= 3.4V
(2)
freq = 0
I
CCD
Supply Current per Input per MHz
V
CC
= Max.
--
0.25
mA/MHz
Outputs Open and Enabled
One Bit Toggling
50% Duty Cycle
Other inputs at GND or Vcc
(3,4)
NOTES:
1. For conditions shown as Min. or Max., use the appropriate values specified under DC Electrical Characteristics.
2. Per TLL driven input (V
IN
= 3.4V).
3. For flip-flops, I
CCD
is measured by switching one of the data input pins so that the output changes every clock cycle. This is a measurement of device power consumption
only and does not include power to drive load capacitance or tester capacitance.
4. I
C
= I
QUIESCENT
+ I
INPUTS
+ I
DYNAMIC
I
C
= I
CC
+
I
CC
D
H
N
T
+ I
CCD
(f
CP
/2 + f
i
N
i
)
I
CC
= Quiescent Current
I
CC
= Power Supply Current for a TTL High Input (V
IN
= 3.4V)
D
H
= Duty Cycle for TTL Inputs High
N
T
= Number of TTL Inputs at D
H
I
CCD
= Dynamic Current Caused by an Output Transition Pair (HLH or LHL)
f
CP
= Clock Frequency for Register Devices (Zero for Non-Register Devices)
f
i
= Input Frequency
N
i
= Number of Inputs at f
i
All currents are in milliamps and all frequencies are in megahertz.
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INDUSTRIAL TEMPERATURE RANGE
IDTQS74FCT2821AT/BT/CT
HIGH-SPEED CMOS BUS INTERFACE 10-BIT REGISTER
FCT2821AT
FCT2821BT
FCT2821CT
Symbol
Parameter
Min.
Max.
Min.
Max.
Min.
Max.
Unit
t
PLH
Clock to Y Delay
--
10
--
7.5
--
6
ns
t
PHL
OE = LOW
t
PLH
Clock to Y Delay
--
20
--
15
--
12.5
ns
t
PHL
OE = LOW
(2)
t
S
Data to CP Setup Time
4
--
3
--
3
--
ns
t
H
Data to CP Hold Time
2
--
1.5
--
1.5
--
ns
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
(1)
NOTES:
1. C
LOAD
= 50pF, R
LOAD
= 500
unless otherwise noted.
2. C
LOAD
= 300pF.
FCT2821AT
FCT2821BT
FCT2821CT
Symbol
Parameter
(2)
Min.
Max.
Min.
Max.
Min.
Max.
Unit
t
PLH
Clock to Y Delay
7
--
6
--
6
--
ns
t
PHL
HIGH or LOW
t
PZH
Output Enable Time
--
12
--
8
--
7
ns
t
PZL
OE to Yx
t
PZH
Output Enable Time
(3)
--
23
--
--
--
--
ns
t
PZL
OE to Yx
t
PHZ
Output Disable Time
(4)
--
7
--
6.5
--
6.2
ns
t
PLZ
OE to Yx
t
PHZ
Output Disable Time
--
9
--
7.5
--
6.5
ns
t
PLZ
OE to Yx
TIMING REQUIREMENTS OVER OPERATING RANGE
(1)
NOTES:
1. C
LOAD
= 50pF, R
LOAD
= 500
unless otherwise noted.
2. See Test Circuits and Waveforms
3. C
LOAD
= 300pF.
4. C
LOAD
= 5pF.
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IDTQS74FCT2821AT/BT/CT
HIGH-SPEED CMOS BUS INTERFACE 10-BIT REGISTER
INDUSTRIAL TEMPERATURE RANGE
Pulse
Generator
R
T
D.U.T.
V
CC
V
IN
C
L
V
OUT
50pF
500
500
7.0V
3V
1.5V
0V
3V
1.5V
0V
3V
1.5V
0V
3V
1.5V
0V
DATA
INPUT
TIMING
INPUT
ASYNCHRONOUS CONTROL
PRESET
CLEAR
ETC.
SYNCHRONOUS CONTROL
t
SU
t
H
t
REM
t
SU
t
H
HIGH-LOW-HIGH
PULSE
LOW-HIGH-LOW
PULSE
t
W
1.5V
1.5V
SAME PHASE
INPUT TRANSITION
3V
1.5V
0V
1.5V
V
OH
t
PLH
OUTPUT
OPPOSITE PHASE
INPUT TRANSITION
3V
1.5V
0V
t
PLH
t
PHL
t
PHL
V
OL
CONTROL
INPUT
3V
1.5V
0V
3.5V
0V
OUTPUT
NORMALLY
LOW
OUTPUT
NORMALLY
HIGH
SWITCH
CLOSED
SWITCH
OPEN
V
OL
0.3V
0.3V
t
PLZ
t
PZL
t
PZH
t
PHZ
3.5V
0V
1.5V
1.5V
ENABLE
DISABLE
V
OH
PRESET
CLEAR
CLOCK ENABLE
ETC.
FCTL link
FCTL link
FCTL link
FCTL link
FCTL link
TEST CIRCUITS AND WAVEFORMS
Propagation Delay
Enable and Disable Times
Set-Up, Hold, and Release Times
Pulse Width
NOTES:
1. Diagram shown for input Control Enable-LOW and input Control Disable-HIGH.
2. Pulse Generator for All Pulses: Rate
1.0MHz; t
F
2.5ns; t
R
2.5ns.
Test
Switch
Open Drain
Disable Low
Closed
Enable Low
All Other Tests
Open
SWITCH POSITION
DEFINITIONS:
C
L
= Load capacitance: includes jig and probe capacitance.
R
T
= Termination resistance: should be equal to Z
OUT
of the Pulse Generator.
Test Circuits for All Outputs
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INDUSTRIAL TEMPERATURE RANGE
IDTQS74FCT2821AT/BT/CT
HIGH-SPEED CMOS BUS INTERFACE 10-BIT REGISTER
ORDERING INFORMATION
High-Speed CMOS Bus Interface 10-Bit Register
2821AT
2821BT
2821CT
74
40C to +85C
SO
Q
Small Outline IC (gull wing)
Quarter-size Small Outline Package
IDTQS
XX
FCT
XXXX
XX
Package
Device Type
Temp. Range
CORPORATE HEADQUARTERS
for SALES:
for Tech Support:
2975 Stender Way
800-345-7015 or 408-727-6116
logichelp@idt.com
Santa Clara, CA 95054
fax: 408-492-8674
(408) 654-6459
www.idt.com
Parameter
Description
Min.
Typ.
Max.
Unit
R
OUT
V
CC
= Min, I
OL
= -15mA
20
28
40
As per PCN L0201-02, the Output Resistance (R
OUT
) specifications have changed as of March 8, 2002. The original specifications were:
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