• Phase-Lock Loop Clock Distribution for Applications ranging
from 10MHz to 133MHz operating frequency
• Distributes one clock input to two banks of four outputs
• Separate output enable for each output bank
• External feedback (FBK) pin is used to synchronize the outputs
to the clock input
• Output Skew <200 ps
• Low jitter <200 ps cycle-to-cycle
• 1x, 2x, 4x output options (see table):
– IDT2308B-1 1x
– IDT2308B-2 1x, 2x
– IDT2308B-3 2x, 4x
– IDT2308B-4 2x
– IDT2308B-1H, -2H, and -5H for High Drive
• No external RC network required
• Operates at 3.3V V
DD
• Available in SOIC and TSSOP packages
DESCRIPTION:
The IDT2308B is a high-speed phase-lock loop (PLL) clock multiplier. It is
designed to address high-speed clock distribution and multiplication applica-
tions. The zero delay is achieved by aligning the phase between the incoming
clock and the output clock, operable within the range of 10 to 133MHz.
The IDT2308B has two banks of four outputs each that are controlled via two
select addresses. By proper selection of input addresses, both banks can be
put in tri-state mode. In test mode, the PLL is turned off, and the input clock
directly drives the outputs for system testing purposes. In the absence of an
input clock, the IDT2308B enters power down, and the outputs are tri-stated.
In this mode, the device will draw less than 25µA.
The IDT2308B is available in six unique configurations for both pre-
scaling and multiplication of the Input REF Clock. (See available options
table.)
The PLL is closed externally to provide more flexibility by allowing the user
to control the delay between the input clock and the outputs.
The IDT2308B is characterized for both Industrial and Commercial opera-
tion.
FUNCTIONAL BLOCK DIAGRAM
(-3, -4)
FBK
REF
16
1
2
(-5)
2
PLL
3
2
CLKA1
CLKA2
14
CLKA3
15
CLKA4
S2
S1
8
9
Control
Logic
(-2, -3)
2
6
CLKB1
7
CLKB2
10
CLKB3
11
CLKB4
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
1
c
2013
Integrated Device Technology, Inc.
OCTOBER 2013
DSC 6995/3
IDT2308B
3.3V ZERO DELAY CLOCK MULTIPLIER
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
(1)
Symbol
V
DD
Rating
Supply Voltage Range
Input Voltage Range (REF)
Input Voltage Range
(except REF)
I
IK
(V
I
< 0)
I
OK
(V
O
< 0 or V
O
> V
DD
)
I
O
(V
O
= 0 to V
DD
)
V
DD
or GND
T
A
= 55°C
(in still air)
(3)
T
STG
Operating
Storage Temperature Range
Commercial Temperature
Range
Industrial Temperature
Range
-40 to +85
°C
–65 to +150
0 to +70
°C
°C
Continuous Current
Maximum Power Dissipation
±100
0.7
mA
W
Input Clamp Current
Terminal Voltage with Respect
to GND (inputs V
IH
2.5, V
IL
2.5)
Continuous Output Current
±50
mA
Max.
–0.5 to +4.6
–0.5 to +5.5
–0.5 to
V
DD
+0.5
–50
±50
mA
mA
Unit
V
V
V
V
I (2)
V
I
REF
CLKA1
CLKA2
V
DD
GND
CLKB1
CLKB2
S2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
FBK
CLKA4
CLKA3
V
DD
GND
CLKB4
CLKB3
S1
SOIC/ TSSOP
TOP VIEW
Temperature
Operating
Temperature
PIN DESCRIPTION
Pin Number
REF
CLKA1
(1)
CLKA2
(1)
V
DD
GND
CLKB1
(1)
CLKB2
(1)
S2
(2)
Functional Description
Input Reference Clock, 5 Volt Tolerant Input
Clock Output for Bank A
Clock Output for Bank A
3.3V Supply
Ground
Clock Output for Bank B
Clock Output for Bank B
Select Input, Bit 2
Select Input, Bit 1
Clock Output for Bank B
Clock Output for Bank B
Ground
3.3V Supply
Clock Output for Bank A
Clock Output for Bank A
PLL Feedback Input
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
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 input and output
clamp-current ratings are observed.
3. The maximum package power dissipation is calculated using a junction temperature
of 150
°
C and a board trace length of 750 mils.
APPLICATIONS:
•
•
•
•
•
SDRAM
Telecom
Datacom
PC Motherboards/Workstations
Critical Path Delay Designs
S1
(2)
CLKB3
(1)
CLKB4
(1)
GND
V
DD
CLKA3
(1)
CLKA4
(1)
FBK
NOTES:
1. Weak pull down on all outputs.
2. Weak pull ups on these inputs.
2
IDT2308B
3.3V ZERO DELAY CLOCK MULTIPLIER
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
FUNCTION TABLE
(1)
SELECT INPUT DECODING
S2
L
L
H
H
NOTE:
1. H = HIGH Voltage Level
L = LOW Voltage Level
S1
L
H
L
H
CLK A
Tri-State
Driven
Driven
Driven
CLK B
Tri-State
Tri-State
Driven
Driven
Output Source
PLL
PLL
REF
PLL
PLL Shut Down
Y
N
Y
N
AVAILABLE OPTIONS FOR IDT2308B
Device
IDT2308B-1
IDT2308B-1H
IDT2308B-2
IDT2308B-2
IDT2308B-2H
IDT2308B-2H
IDT2308B-3
IDT2308B-3
IDT2308B-4
IDT2308B-5H
Feedback From
Bank A or Bank B
Bank A or Bank B
Bank A
Bank B
Bank A
Bank B
Bank A
Bank B
Bank A or Bank B
Bank A or Bank B
Bank A Frequency
Reference
Reference
Reference
2 x Reference
Reference
2 x Reference
2 x Reference
4 x Reference
2 x Reference
Reference/2
Bank B Frequency
Reference
Reference
Reference/2
Reference
Reference/2
Reference
Reference or
Reference
(1)
2 x Reference
2 x Reference
Reference/2
NOTE:
1. Output phase is indeterminant (0° or 180° from input clock).
3
IDT2308B
3.3V ZERO DELAY CLOCK MULTIPLIER
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
ZERO DELAY AND SKEW CONTROL
To close the feedback loop of the IDT2308B, the FBK pin can be driven from any of the eight available output pins. The output driving the FBK pin
will be driving a total load of 7pF plus any additional load that it drives. The relative loading of this output (with respect to the remaining outputs) can adjust
the input-output delay.
For applications requiring zero input-output delay, all outputs including the one providing feedback should be equally loaded. If input-output delay
adjustments are required, use the Output Load Difference Chart to calculate loading differences between the feedback output and remaining outputs.
Ensure the outputs are loaded equally, for zero output-output skew.
REF TO CLKA/CLKB DELAY vs. OUTPUT LOAD DIFFERENCE BETWEEN FBK PIN AND CLKA/CLKB PINS
1500
1000
REF to CLKA/CLKB Delay (ps)
500
0
-30
-25
-20
-15
-10
-5
0
5
10
15
20
25
30
-500
-1000
-1500
OUTPUT LOAD DIFFERENCE BETWEEN FBK PIN AND CLKA/CLKB PINS ( pF)
I just received an email from the DHL Information Center in my frequently used school mailbox. It said that my express package could not be delivered due to an unclear address. I need to click on the ...
The kernel provides basic services for applications. In order to support stream interface drivers, the kernel redirects the application's file I/0 functions to the appropriate stream interface driver ...
I use PWM to control two servos. I connect two axes. I tested it and it can walk a circle, but the speed is too slow. Has anyone done this before? Can you give me some advice? I'd be grateful....
The original memory of BSP was 64M, but now it has been changed to 128M. The system can run, but it is just a normal standby function, and it stops when it starts. I hope experts can give me some advi...
Gray Code (English: Gray Code, Grey Code, also known as Gray code, binary cyclic code)
It is a code invented by French engineer Jean-Maurice-Emlle Baudot in 1880 and is an absolute coding method.
The ...
introduction
With the continuous optimization of surface mount technology (SMT) and the rapid development of chip component manufacturing technology, the application of chip mounters in the el...[Details]
1. Introduction
Automobile pollution is one of the most important issues that people are most concerned about and need to solve urgently. As an important method for detecting automobile exhau...[Details]
The Portable Digital Data Acquisition System (PDDAS) uses LabVIEW Real-Time and PXI to control the wind tunnel test and record air pressure data from 128 different channels.
"The LabVIEW Real-...[Details]
My colleague and I spent the day chatting in the hotel bar. We had met with several customers. We were both wondering how come these engineers we were meeting knew almost nothing about analog techn...[Details]
The data collector of the automatic weather station is generally designed based on a single-chip microcomputer or a PC/104 bus controller. It has the characteristics of good compatibility with PC, low...[Details]
A multi-point temperature control heating control system was designed using the SST89E564RC single-chip microcomputer and a new temperature measuring device. The heating system can be controlled in...[Details]
1. What is temperature?
Heat is a type of molecular motion. The hotter an object is, the faster its molecules move. Absolute zero is defined as the temperature at which all molecular motion ...[Details]
my country is a big country in agriculture, grain production and consumption. Grains are a necessary condition for our nation to survive and develop. The flour processing industry will exist forever w...[Details]
In the analysis of electronic circuits, static analysis (also known as DC analysis) is the basis of circuit analysis. However, it is well known that electronic components are nonlinear, so the anal...[Details]
RS-422 and RS-485 are both serial data interface standards, which were developed and published by the Electronic Industries Association (EIA). RS-422 defines a balanced communication interface with a ...[Details]
This paper designs a 16x16LED Chinese character display bar based on single-chip dynamic scanning control, briefly analyzes the principle of Chinese character display, and studies how the LED displ...[Details]
Continuity test
A variety of devices need to be checked for continuity, including cable assemblies, printed circuit boards, and connectors to ensure that these components have the expected contin...[Details]
Describe how to meet the challenges of complexity with a modern wiring design toolset. Option codes and expressions can simulate the variables of an automotive project. A full-featured tool suite c...[Details]
1. Overview
At present, an information revolution is in the ascendant around the world, led by microelectronics, computers and communication technologies, and centered on information technolog...[Details]
1 Introduction
With the improvement of people's quality of life, lamps are no longer just basic indoor lighting tools, but also a kind of practical art for architectural decoration. When ther...[Details]
NXP MCU
京公网安备 11010802033920号
EEWORLD
