IDT74SSTV16857
14-BIT REGISTERED BUFFER WITH SSTL I/O
INDUSTRIAL TEMPERATURE RANGE
14-BIT REGISTERED
BUFFER WITH SSTL I/O
IDT74SSTV16857
FEATURES:
•
•
•
•
•
•
•
•
2.3V to 2.7V Operation
SSTL_2 Class II style data inputs/outputs
Differential CLK input
RESET
control compatible with LVCMOS levels
Flow-through architecture for optimum PCB design
Drive up to equivalent of 14 SDRAM loads
Latch-up performance exceeds 100mA
ESD >2000V per MIL-STD-883, Method 3015; >200V using
machine model (C = 200pF, R = 0)
• Available in TSSOP package
DESCRIPTION:
The SSTV16857 is a 14-bit registered buffer designed for 2.3V-2.7V
V
DD
and supports low standby operation. All data inputs and outputs are
SSTL_2 level compatible with JEDEC standard for SSTL_2.
RESET
is an LVCMOS input since it must operate predictably during the
power-up phase.
RESET,
which can be operated independent of CLK and
CLK,
must be held in the low state during power-up in order to ensure
predictable outputs (low state) before a stable clock has been applied.
RESET,
when in the low state, will disable all input receivers, reset all
registers, and force all outputs to a low state, before a stable clock has been
applied. With inputs held low and a stable clock applied, outputs will remain
low during the Low-to-High transition of
RESET.
APPLICATIONS:
• Ideally suited for DIMM DDR registered applications
FUNCTIONAL BLOCK DIAGRAM
RESET
34
CK
CK
38
39
V
REF
35
D1
48
1D
1
C1
R
Q1
TO 13 OTHER CHANNELS
INDUSTRIAL TEMPERATURE RANGE
1
c
2003 Integrated Device Technology, Inc.
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
MAY 2003
DSC-5737/5
IDT74SSTV16857
14-BIT REGISTERED BUFFER WITH SSTL I/O
INDUSTRIAL TEMPERATURE RANGE
PIN CONFIGURATION
Q
1
Q
2
GND
V
DDQ
Q
3
Q
4
Q
5
GND
V
DDQ
Q
6
Q
7
V
DDQ
GND
Q
8
Q
9
V
DDQ
GND
Q
10
Q
11
Q
12
V
DDQ
GND
Q
13
Q
14
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
D
1
D
2
GND
V
DD
D
3
D
4
D
5
D
6
D
7
CLK
CLK
V
DD
GND
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
I
(2)
(3)
Description
Input Voltage Range
Output Voltage Range
Input Clamp Current, V
I
< 0
Output Clamp Current,
V
O
< 0 or V
O
> V
DDQ
Continuous Output Current,
V
O
= 0 to V
DDQ
Continuous Current through each
V
DD
, V
DDQ
or GND
Storage Temperature Range
Max.
–0.5 to 3.6
–0.5 to V
DD
+0.5
–0.5 to V
DDQ
+0.5
–50
±50
±50
±100
–65 to +150
Unit
V
V
V
mA
mA
mA
mA
°C
V
DD
or V
DDQ
Supply Voltage Range
V
O
I
IK
I
OK
I
O
V
DD
T
STG
V
REF
RESET
D
8
D
9
D
10
D
11
D
12
V
DD
GND
D
13
D
14
NOTES:
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.
2. The input and output negative voltage ratings may be exceeded if the ratings of the
I/P and O/P clamp current are observed.
3. The output current will flow if the following conditions are observed:
a) Output in HIGH state
b) V
O
= V
DDQ
FUNCTION TABLE
(1)
Input
RESET
H
H
H
L
CLK
↑
↑
L or H
X
CLK
↓
↓
L or H
X
D
L
H
X
X
Q Outputs
L
H
Q
(2)
L
TSSOP
TOP VIEW
NOTES:
1. H = HIGH Voltage Level
L = LOW Voltage Level
X = Don’t Care
↑
= LOW to HIGH
↓
= HIGH to LOW
2. Q = Output level before the indicated steady-state conditions were established.
2
IDT74SSTV16857
14-BIT REGISTERED BUFFER WITH SSTL I/O
INDUSTRIAL TEMPERATURE RANGE
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified:
Operating Condition: T
A
= –40°C to +85°C, V
DD
= 2.5V ±0.2V, V
DDQ
= 2.5V ±0.2V
Symbol
V
IK
V
OH
V
OL
I
I
I
DD
I
DDD
All Inputs
Static Standby
Static Operating
Dynamic Operating (Clock Only)
Dynamic Operating
(Per Each Data Input)
r
OH
r
OL
r
O(∆)
C
I
Output HIGH
Output LOW
| r
OH
- r
OL
| each separate bit
Data Inputs
CLK and
CLK
RESET
Parameter
Control Inputs
Test Conditions
V
DD
= 2.3V, I
I
=
−18mA
V
DD
= 2.3V to 2.7V, I
OH
= -100µA
V
DD
= 2.3V, I
OH
= -16mA
V
DD
= 2.3V to 2.7V, I
OL
= 100µA
V
DD
= 2.3V, I
OL
= 16mA
V
DD
= 2.7V, VI = V
DD
or GND
I
O
= 0, V
DD
= 2.7V,
RESET
= GND
I
O
= 0, V
DD
= 2.7V,
RESET
= V
DD
, V
I
= V
IH (AC)
or V
IL (AC)
I
O
= 0, V
DD
= 2.7V,
RESET
= V
DD
, V
I
= V
IH (AC)
or V
IL (AC)
,
CLK and
CLK
Switching 50% Duty Cycle.
I
O
= 0, V
DD
= 2.7V,
RESET
= V
DD
, V
I
= V
IH (AC)
or V
IL (AC)
,
CLK and
CLK
Switching 50% Duty Cycle. One Data Input
Switching at Half Clock Frequency, 50% Duty Cycle.
V
DD
= 2.3V to 2.7V, I
OH
= -20mA
V
DD
= 2.3V to 2.7V, I
OH
= 20mA
V
DD
= 2.5V, T
A
= 25°C, I
OH
= -20mA
V
DD
= 2.5V, V
I
= V
REF
±
310mV
V
ICR
= 1.25V, V
I (PP)
= 360mV
V
I
= V
DD
or GND
7
7
—
2.5
2.5
—
—
—
—
—
—
—
20
20
4
3.5
3.5
—
pF
—
—
—
Min.
—
V
DD
– 0.2
1.95
—
—
—
—
—
—
Typ.
—
—
—
—
—
—
—
—
—
Max.
–1.2
—
—
0.2
0.35
±5
0.01
—
—
µA/Clock
MHz
µA/Clock
MHz/Data
Input
Ω
Ω
Ω
µA
mA
V
Unit
V
V
OPERATING CHARACTERISTICS, T
A
= 25ºC
(1)
Symbol
V
DD
V
DDQ
V
REF
V
TT
V
I
V
IH
V
IL
V
IH
V
IL
V
IH
V
IL
V
ICR
V
I (PP)
I
OH
I
OL
T
A
NOTE:
1.
The
RESET
input of the device must be held at V
DD
or GND to ensure proper device operation.
Parameter
Supply Voltage
Output Supply Voltage
Reference Voltage (V
REF
= V
DDQ
/2)
Termination Voltage
Input Voltage
AC High-Level Input Voltage
AC Low-Level Input Voltage
DC High-Level Input Voltage
DC Low-Level Input Voltage
High-Level Input Voltage
Low-Level Input Voltage
Common-Mode Input Range
Peak-to-Peak Input Voltage
High-Level Output Current
Low-Level Output Current
Operating Free-Air Temperature
Data Inputs
Data Inputs
Data Inputs
Data Inputs
RESET
RESET
CLK,
CLK
CLK,
CLK
Min.
V
DDQ
2.3
1.15
V
REF
– 40mV
0
V
REF
+ 310mV
—
V
REF
+ 150mV
—
1.7
—
0.97
360
—
—
– 40
Typ.
—
2.5
1.25
V
REF
—
—
—
—
—
—
—
—
—
—
—
—
Max.
2.7
2.7
1.35
V
REF
+ 40mV
V
DD
—
V
REF
– 310mV
—
V
REF
– 150mV
—
0.7
1.53
—
– 20
20
+85
Unit
V
V
V
V
V
V
V
V
V
V
V
V
mV
mA
°C
3
IDT74SSTV16857
14-BIT REGISTERED BUFFER WITH SSTL I/O
INDUSTRIAL TEMPERATURE RANGE
TIMING REQUIREMENTS OVER RECOMMENDED OPERATING FREE-AIR
TEMPERATURE RANGE
V
DD
= 2.5V
±
0.2V
Symbol
CLOCK
Parameter
Clock Frequency
Pulse Duration, CLK,
CLK
HIGH or LOW
Differential Inputs Active Time
(1)
Differential Inputs Inactive Time
(2)
Setup Time, Fast Slew Rate
(3, 5)
Setup Time, Slow Slew Rate
(4, 5)
Min.
—
2.5
—
—
Data Before CLK↑, CLK↓
Data Before CLK↑, CLK
↓
0.75
0.9
0.75
0.9
Max.
200
—
22
22
—
—
—
—
Unit
MHz
ns
ns
ns
ns
ns
ns
ns
tw
t
ACT
t
INACT
t
SU
t
N
Hold Time, Fast Slew Rate
(3,5)
Hold Time, Slow Slew Rate
(2,5)
NOTES:
1. Data inputs must be low a minimum time of t
ACT
max., after
RESET
is taken HIGH.
2. Data and clock inputs must be held at valid levels (not floating) a minimum time of t
INACT
max., after
RESET
is taken LOW.
3. For data signal input slew rate is
≥1V/ns.
4. For data signal input slew rate is
≥0.5V/ns
and <1V/ns.
5. CLK,
CLK
signal input slew rates are
≥1V/ns.
SWITCHING CHARACTERISTICS OVER RECOMMENDED FREE-AIR OPERATING
RANGE (UNLESS OTHERWISE NOTED)
V
DD
= 2.5V ± 0.2V
Symbol
f
MAX
t
PD
t
PHL
Parameter
CLK and
CLK
to Q
RESET
to Q
Min
200
1.1
—
Max.
—
2.8
5
Unit
MHz
ns
ns
4
IDT74SSTV16857
14-BIT REGISTERED BUFFER WITH SSTL I/O
INDUSTRIAL TEMPERATURE RANGE
TEST CIRCUITS AND WAVEFORMS (V
DD
= 2.5V ± 0.2V)
V
TT
R
L
= 50
Ω
From Output
Under Test
Test Point
C
L
= 30 pF
(see note 1)
Load Circuit
LVCMOS
RESE T
Input
t
IN AC T
I
D D
(see note 2)
V
DD
V
D D
/2
V
D D
/2
0V
Timing
Input
t
PLH
Output
V
IC R
V
IC R
V
I(P P)
t
AC T
10%
90%
t
PH L
V
OH
V
TT
V
TT
V
OL
Voltage and Current Waveforms
Inputs Active and Inactive Times
Voltage Waveforms - Propagation Delay Times
LVCMOS
RESE T
Input
V
IH
V
D D
/2
V
IL
t
PH L
t
W
V
IH
Input
V
REF
V
R EF
V
IL
Output
V
TT
V
OL
V
OH
Voltage Waveforms - Pulse Duration
Voltage Waveforms - Propagation Delay Times
Timing
Input
V
IC R
V
I(PP )
t
SU
Input
V
RE F
t
N
V
IH
V
RE F
V
IL
Voltage Waveforms - Setup and Hold Times
NOTES:
1. C
L
includes probe and jig capacitance.
2. I
DD
tested with clock and data inputs held at V
DD
or GND, and I
O
= 0mA.
3. All input pulses are supplied by generators having the following characteristics: PRR
≤10MHz,
Z
O
= 50Ω, input slew rate = 1 V/ns ±20% (unless otherwise specified).
4. The outputs are measured one at a time with one transition per measurement.
5. V
TT
= V
REF
= V
DDQ
/2
6. V
IH
= V
REF
+ 310mV (AC voltage levels) for differential inputs. V
IH
= V
DD
for LVCMOS input.
7. V
IL
= V
REF
- 310mV (AC voltage levels) for differential inputs. V
IL
= GND for LVCMOS input.
8. t
PLH
and t
PHL
are the same as t
PD
.
5