ICST ICS87931I Low skew, 1-to-6 lvcmos/lvttl clock multiplier/zero delay buffer Datasheet

ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
GENERAL DESCRIPTION
FEATURES
The ICS87931I is a low voltage, low skew
LVCMOS/LVTTL Clock Multiplier/Zero Delay
HiPerClockS™
Buffer and a member of the HiPerClockS™ family
of High Performance Clock Solutions from ICS.
With output frequencies up to 150MHz, the
ICS87931I is targeted for high performance clock applications.
Along with a fully integrated PLL, the ICS87931I contains frequency configurable outputs and an external feedback input for
regenerating clocks with “zero delay”.
• Fully integrated PLL
,&6
• 6 LVCMOS/LVTTL outputs, 7Ω typical output impedance
• Selectable differential CLK0, nCLK0 or LVCMOS/LVTTL clock
for redundant clock applications
• Maximum output frequency: 150MHz
• VCO range: 220MHz to 480MHz
• External feedback for “zero delay” clock regeneration
• Output skew, Same Frequency: 300ps (maximum)
Selectable clock inputs, CLK1 and differential CLK0, nCLK0
support redundant clock applications. The CLK_SEL input determines which reference clock is used. The output divider values of Bank A, B and C are controlled by the DIV_SELA,
DIV_SELB and DIV_SELC, respectively.
• Output skew, Different Frequency: 400ps (maximum)
• Cycle-to-cycle jitter: 100ps (maximum)
• 3.3V supply voltage
• -40°C to 85°C ambient operating temperature
For test and system debug purposes, the PLL_SEL input allows the PLL to be bypassed. When LOW, the nMR input resets the internal dividers and forces the outputs to the high impedance state.
• Pin compatible with MPC931
PIN ASSIGNMENT
GND
QA1
QA0
VDDO
DIV_SELA
DIV_SELB
DIV_SELC
nc
The effective fanout of the ICS87931I can be increased to 12
by utilizing the ability of each output to drive two series terminated transmission lines.
32 31 30 29 28 27 26 25
nc
1
24
GND
VDDA
2
23
QB0
POWER_DN
3
22
QB1
CLK1
4
21
VDDO
nMR
5
20
EXTFB_SEL
CLK0
6
19
CLK_SEL
nCLK0
7
18
PLL_SEL
GND
8
17
nc
BLOCK DIAGRAM
GND
QC1
QC0
VDDO
EXTFB_SEL Pulldown
EXT_FB Pullup
0
1
0
EXT_FB
nCLK0 None
CLK_EN1
CLK_SEL Pulldown
CLK1 Pullup
CLK_EN0
nc
PLL_SEL Pullup
Pullup
32-Lead LQFP
7mm x 7mm x 1.4mm
package body
Y package
Top View
9 10 11 12 13 14 15 16
POWER_DN Pullup
CLK0
ICS87931I
0
PHASE
DETECTOR
1
VCO
÷2
÷2/÷4
QA1
LPF
1
÷2/÷4
÷8
0
QA0
1
QB0
QB1
DIV_SELA Pulldown
DIV_SELB Pulldown
÷4/÷6
CLK_EN0 Pullup
DISABLE
LOGIC
CLK_EN1 Pullup
DIV_SELC Pulldown
nMR Pullup
87931BYI
QC0
QC1
POWER-ON RESET
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1
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
TABLE 1. PIN DESCRIPTIONS
Number
Name
1, 9, 17, 32
nc
Unused
2
VDDA
Power
3
POWER_DN
Input
Pullup
4
CLK1
Input
Pullup
5
nMR
Input
Pullup
6
CLK0
Input
7
nCLK0
Input
8, 16, 24,25
GND
CLK_EN0,
CLK_EN1
Power
12
EXT_FB
Input
13, 21, 28
VDDO
Power
14, 15
QC0, QC1
Output
18
PLL_SEL
Input
19
CLK_SEL
Input
20
EXTFB_SEL
Input
22, 23
QB1, QB0
Output
26, 27
QA1, QA0
Output
29
DIV_SELA
Input
30
DIV_SELB
Input
31
DIV_SELC
Input
10, 11
Type
Input
Description
No connect.
Analog supply pin.
Controls the frequency being fed to the output dividers.
LVCMOS / LVTTL interface levels.
Clock input. LVCMOS / LVTTL interface levels.
Active LOW Master reset. When logic LOW, the internal dividers are
reset causing the outputs to go low. When logic HIGH, the internal
dividers and the outputs are enabled. LVCMOS / LVTTL interface levels.
Non-inver ting differential clock input.
Pullup
Pullup/
Inver ting differential clock input. VCC/2 default when left floating.
Pulldown
Power supply ground.
Controls the enabling and disabling of the clock outputs. See Table 3B.
Pullup
LVCMOS / LVTTL interface levels.
External feedback. When LOW, selects internal feedback.
Pullup
When HIGH, selects EXT_FB. LVCMOS / LVTTL interface levels.
Output supply pins.
Bank C clock outputs.7Ω typical output impedance.
LVCMOS / LVTTL interface levels.
Selects between the PLL and reference clocks as the input to the
Pullup
output dividers. When HIGH, selects PLL. When LOW, bypasses
the PLL. LVCMOS / LVTTL interface levels.
Clock select input. Selects the Phase Detector Reference.
Pulldown When LOW, selects CLK0, nCLK0. When HIGH, selects CLK1.
LVCMOS / LVTTL interface levels.
Pulldown External feedback select. LVCMOS / LVTTL interface levels.
Bank B clock outputs.7Ω typical output impedance.
LVCMOS / LVTTL interface levels.
Bank A clock outputs.7Ω typical output impedance.
LVCMOS / LVTTL interface levels.
Determines output divider values for Bank A as described in Table 4A.
Pulldown
LVCMOS / LVTTL interface levels.
Determines output divider values for Bank B as described in Table 4A.
Pulldown
LVCMOS / LVTTL interface levels.
Determines output divider values for Bank C as described in Table 4A.
Pulldown
LVCMOS / LVTTL interface levels.
NOTE: Pullup and Pulldown refer to internal input resistors. See table 2, Pin Characteristics, for typical values.
TABLE 2. PIN CHARACTERISTICS
Symbol
Parameter
Test Conditions
Minimum
Typical
Maximum
Units
CIN
Input Capacitance
4
pF
RPULLUP
Input Pullup Resistor
51
KΩ
RPULLDOWN
Input Pulldown Resistor
Power Dissipation Capacitance
(per output)
Output Impedance
51
KΩ
12
pF
7
Ω
CPD
ROUT
87931BYI
VDDA, VDDO = 3.465V
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2
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
TABLE 3A. CONTROL INPUT FUNCTION TABLE
Inputs
Function
Control Pin
Logic 0
Logic 1
CLK_SEL
CLK0, nCLK0
CLK1
PLL_SEL
Bypass PLL
PLL Enabled
EXTFB_SEL
Internal Feedback
EXT_FB
POWER_DN
VCO/1
VCO/2
nMR
Master Reset/Output Hi Z
Enable Outputs
DIV_SELA:DIV_SELC
QA(÷2); QB(÷2); QC(÷4)
QA(÷4); QB(÷4); QC(÷6)
TABLE 3B. CLK_ENX FUNCTION TABLE
Inputs
CLK_EN1
CLK_EN0
0
0
1
0
1
1
DIV_SELA:DIVSELC
QAx
QBx
QCx
0
Toggle
LOW
LOW
1
LOW
LOW
Toggle
Toggle
LOW
Toggle
Toggle
Toggle
Toggle
TABLE 4A. VCO FREQUENCY FUNCTION TABLE
Inputs
Outputs
QAx
QBx
QCx
DIV_
SELA
DIV_
SELB
DIV_
SELC
POWER_DN = 0
0
0
0
VCO/2
VCO/4
VCO/2
VCO/4
VCO/4
VCO/8
0
0
1
VCO/2
VCO/4
VCO/2
VCO/4
VCO/6
VCO/12
0
1
0
VCO/2
VCO/4
VCO/4
VCO/8
VCO/4
VCO/8
POWER_DN = 1 POWER_DN = 0
POWER_DN = 1 POWER_DN = 0
POWER_DN = 1
0
1
1
VCO/2
VCO/4
VCO/4
VCO/8
VCO/6
VCO/12
1
0
0
VCO/4
VCO/8
VCO/2
VCO/4
VCO/4
VCO/8
1
0
1
VCO/4
VCO/8
VCO/2
VCO/4
VCO/6
VCO/12
1
1
0
VCO/4
VCO/8
VCO/4
VCO/8
VCO/4
VCO/8
1
1
1
VCO/4
VCO/8
VCO/4
VCO/8
VCO/6
VCO/12
TABLE 4B. INPUT REFERENCE FREQUENCY
TO
OUTPUT FREQUENCY FUNCTION TABLE (INTERNAL FEEDBACK ONLY)
Inputs
Outputs
QAx
QBx
QCx
DIV_
SELA
DIV_
SELB
DIV_
SELC
POWER_DN = 0
0
0
0
4x
2x
4x
2x
2x
x
0
0
1
4x
2x
4x
2x
4/3x
2/3x
0
1
0
4x
2x
2x
x
2x
x
POWER_DN = 1 POWER_DN = 0
POWER_DN = 1 POWER_DN = 0
POWER_DN = 1
0
1
1
4x
2x
2x
x
4/3x
2/3x
1
0
0
2x
x
4x
2x
2x
x
1
0
1
2x
x
4x
2x
4/3x
2/3x
1
1
0
2x
x
2x
x
2x
x
1
1
1
2x
x
2x
x
4/3x
2/3x
87931BYI
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REV. A JUNE 23, 2003
Integrated
Circuit
Systems, Inc.
ICS87931I
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
VCO
VCO/2
POWER_DN
QA(÷2)
QB(÷4)
QC(÷6)
FIGURE 1A. POWER_DN TIMING DIAGRAM
QA
QB
QC
CLK_EN0
CLK_EN1
QA(÷2)
QB(÷4)
QC(÷6)
CLK_EN0
CLK_EN1
FIGURE 1B. CLK_ENX TIMING DIAGRAMS
87931BYI
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4
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VDD
4.6V
Inputs, VI
-0.5V to VDDA + 0.5 V
Outputs, VO
-0.5V to VDDO + 0.5V
Package Thermal Impedance, θJA
47.9°C/W (0 lfpm)
Storage Temperature, TSTG
-65°C to 150°C
NOTE: Stresses beyond those listed under Absolute
Maximum Ratings may cause permanent damage to the
device. These ratings are stress specifications only. Functional
operation of product at these conditions or any conditions beyond those listed in the DC Characteristics or AC Characteristics is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect product reliability.
TABLE 5A. POWER SUPPLY DC CHARACTERISTICS, VDDA = VDDO = 3.3V±5%, TA = -40°C TO 85°C
Symbol
Parameter
VDDA
Test Conditions
Minimum
Typical
Maximum
Units
Analog Supply Voltage
3.135
3.3
3.465
V
3.135
3.3
3.465
VDDO
Output Supply Voltage
IDDA
Analog Supply Current
20
mA
V
IDDO
Output Supply Current
100
mA
TABLE 5B. LVCMOS/LVTTL DC CHARACTERISTICS, VDDA = VDDO = 3.3V±5%, TA = -40°C TO 85°C
Symbol Parameter
VIH
Input
High Voltage
VIL
Input
Low Voltage
IIN
Input Current
Test Conditions
DIV_SELA:DIV_SELC,
CLK_EN0, CLK_EN1,
POWER_DN, nMR, CLK_SEL,
PLL_SEL, EXTFB_SEL
CLK1, EXT_FB
DIV_SELA:DIV_SELC,
CLK_EN0, CLK_EN1,
POWER_DN, nMR, CLK_SEL,
PLL_SEL, EXTFB_SEL
CLK1, EXT_FB
Minimum Typical
Maximum
Units
2
VDD + 0.3
V
2
VDD + 0.3
V
-0.3
0.8
V
-0.3
VOH
Output High Voltage; NOTE 1
IOH = -20mA
VOL
Output Low Voltage; NOTE 1
IOL = 20mA
1.3
V
±120
µA
2.4
V
0.5
V
NOTE 1: Outputs terminated with 50Ω to VDDO/2. See Parameter Measurement section, 3.3V Output Load Test Circuit.
TABLE 5C. DIFFERENTIAL DC CHARACTERISTICS, VDDA = VDDO = 3.3V±5%, TA = -40°C TO 85°C
Symbol
Parameter
IIN
Input Current
Test Conditions
Minimum
Typical
Peak-to-Peak Input Voltage
0.15
Common Mode Input Voltage;
VCMR
GND + 0.5
NOTE 1, 2
NOTE 1: For single ended applications, the maximum input voltage for CLK0, nCLK0 is VDDA + 0.3V.
NOTE 2: Common mode voltage is defined as VIH.
VPP
87931BYI
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5
Maximum
Units
±120
µA
1.3
V
VDD - 0.85
V
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
TABLE 6. PLL INPUT REFERENCE CHARACTERISTICS, VDDA = VDDO = 3.3V±5%, TA = -40°C TO 85°C
Symbol Parameter
Input Reference Frequency
fREF
NOTE: Input reference frequency is limited by
the divider selection and the VCO lock range.
Test Conditions
Minimum
Typical
Maximum
Units
150
MHz
Maximum
Units
TABLE 7. AC CHARACTERISTICS, VDDA = VDDO = 3.3V±5%, TA = -40°C TO 85°C
Symbol
fMAX
Parameter
Output Frequency
Test Conditions
Minimum
Typical
QAx, QBx
÷2
150
MHz
QAx, QBx, QCx
÷4
120
MHz
QCx
÷6
80
MHz
CLK1 to EXT_FB
tPD
Propagation Delay;
NOTE 1
tsk(o)
Output Skew; NOTE 2, 4
-375
-200
-50
ps
-100
50
200
ps
Same Frequency
300
ps
Different Frequency
400
ps
fref = 50MHz,
FB = ÷ 8
CLK0, nCLK0 to EXT_FB
tjitter(cc)
Cycle-to-Cycle Jitter ; NOTE 4
fVCO
PLL VCO Lock Range
tR/tF
Output Rise Time; NOTE 3
odc
Output Duty Cycle
tLOCK
PLL Lock Time
tPZL, tPZH
Output Enable Time; NOTE 3
0.8V to 2.0V
100
ps
220
480
MHz
0.1
1
ns
45
55
%
10
ms
10
ns
8
ns
2
Output Disable Time; NOTE 3
2
tPLZ, tPHZ
All parameters measured at fMAX unless noted otherwise.
NOTE 1: Measured from the differential input crossing point to VDDO/2 of the output
NOTE 2: Defined as skew between outputs at the same supply voltage and with equal load conditions.
Measured at VDDO/2.
NOTE 3: These parameters are guaranteed by characterization. Not tested in production.
NOTE 4: This parameter is defined in accordance with JEDEC Standard 65.
87931BYI
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6
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
PARAMETER MEASUREMENT INFORMATION
VDDA, VDDO = 1.65V±5%
VDDA
SCOPE
nCLK0
Qx
LVCMOS
V
V
Cross Points
PP
CMR
CLK0
GND
GND = -1.165V±5%
3.3V OUTPUT LOAD AC TEST CIRCUIT
DIFFERENTIAL INPUT LEVEL
V
V
DDO
V
DDO
V
DDO
2
DDO
2
tcycle
➤
QAx,
QBx,
QCx
2
n
➤
Qx
➤
2
tcycle n+1
➤
V
DDO
2
tsk(o)
Qy
t jit(cc) = tcycle n –tcycle n+1
1000 Cycles
OUTPUT SKEW
CYCLE-TO-CYCLE JITTER
2V
2V
0.8V
0.8V
Clock Outputs
t
t
R
CLK1
VDD
2
F
nCLK0
CLK0
OUTPUT RISE/FALL TIME
EXT_FB
V
DDO
VDDO
2
2
QAx, QBx, QCx
Pulse Width
t
odc =
odc & tPERIOD
87931BYI
PERIOD
t PW
t PERIOD
PROPAGATION DELAY
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7
REV. A JUNE 23, 2003
Integrated
Circuit
Systems, Inc.
ICS87931I
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
APPLICATION INFORMATION
WIRING
THE
DIFFERENTIAL INPUT TO ACCEPT SINGLE ENDED LEVELS
Figure 2 shows how the differential input can be wired to accept
single ended levels. The reference voltage V_REF = VDD/2 is
generated by the bias resistors R1, R2 and C1. This bias circuit
should be located as close as possible to the input pin. The ratio
of R1 and R2 might need to be adjusted to position the V_REF in
the center of the input voltage swing. For example, if the input
clock swing is only 2.5V and VDD = 3.3V, V_REF should be 1.25V
and R2/R1 = 0.609.
VDD
R1
1K
Single Ended Clock Input
CLK
V_REF
nCLK
C1
0.1u
R2
1K
FIGURE 2. SINGLE ENDED SIGNAL DRIVING DIFFERENTIAL INPUT
87931BYI
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8
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
DIFFERENTIAL CLOCK INPUT INTERFACE
here are examples only. Please consult with the vendor of the
driver component to confirm the driver termination requirements.
For example in Figure 3A, the input termination applies for ICS
HiPerClockS LVHSTL drivers. If you are using an LVHSTL driver
from another vendor, use their termination recommendation.
The CLK /nCLK accepts LVDS, LVPECL, LVHSTL, SSTL, HCSL
and other differential signals. Both VSWING and VOH must meet the
VPP and VCMR input requirements. Figures 3A to 3D show interface examples for the HiPerClockS CLK/nCLK input driven by
the most common driver types. The input interfaces suggested
3.3V
3.3V
3.3V
1.8V
Zo = 50 Ohm
CLK
Zo = 50 Ohm
CLK
Zo = 50 Ohm
nCLK
Zo = 50 Ohm
LVPECL
nCLK
HiPerClockS
Input
LVHSTL
ICS
HiPerClockS
LVHSTL Driver
R1
50
R1
50
HiPerClockS
Input
R2
50
R2
50
R3
50
FIGURE 3A. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
ICS HIPERCLOCKS LVHSTL DRIVER
FIGURE 3B. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER
BY
3.3V
3.3V
3.3V
3.3V
3.3V
R3
125
BY
R4
125
Zo = 50 Ohm
LVDS_Driv er
Zo = 50 Ohm
CLK
CLK
R1
100
Zo = 50 Ohm
nCLK
LVPECL
R1
84
HiPerClockS
Input
Receiv er
R2
84
FIGURE 3C. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVPECL DRIVER
87931BYI
nCLK
Zo = 50 Ohm
FIGURE 3D. HIPERCLOCKS CLK/NCLK INPUT DRIVEN
3.3V LVDS DRIVER
BY
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9
BY
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
SCHEMATIC EXAMPLE
Figure 4A shows a schematic example of using an ICS87931I. It
is recommended to have one decouple capacitor per power pin.
Each decoupling capacitor should be located as close as pos-
sible to the power pin. The low pass filter R7, C11 and C16 for
clean analog supply should also be located as close to the VDDA
pin as possible.
R1
DIV_SELC
DIV_SELB
DIV_SELA
VDD
R7
10 - 15
43
Zo = 50
VDD
Receiv er
32
31
30
29
28
27
26
25
C11
0.01u
POWER_DN
Zo = 50 Ohm
Zo = 50 Ohm
1
2
3
4
5
6
7
8
nc
VDDA
POWER_DN
CLK1
nMR
CLK0
nCLK0
GND
3.3V PECL Driv er
R8
50
R9
50
ICS87931I
GND
QB0
QB1
VDDO
EXTFB_SEL
CLK_SEL
PLL_SEL
nc
nc
CLK_EN0
CLK_EN1
EXT_FB
VDDO
QC0
QC1
GND
3.3V
24
23
22
21
20
19
18
17
R3
1K
R4
1K
R5
1K
9
10
11
12
13
14
15
16
C16
10u
VDD
nc
DIV_SELC
DIV_SELB
DIV_SELA
VDDO
QA0
QA1
GND
U1
Set Logic
Input to
’1’
VDD
RU1
1K
Set Logic
Input to
’0’
VDD
R10
50
CLK_EN0
CLK_EN1
Logic Input Pin Examples
Zo = 50
R2
43
RU2
Not Install
To Logic
Input
pins
RD1
Not Install
Receiv er
To Logic
Input
pins
RD2
1K
(U1-13)
VDD
C1
0.1uF
VDD=3.3V
(U1-21)
C2
0.1uF
(U1-28)
C3
0.1uF
SP = Space (i.e. not intstalled)
FIGURE 4A. ICS87931I SCHEMATIC EXAMPLE
87931BYI
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REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
The following component footprints are used in this layout
example:
trace delay might be restricted by the available space on the board
and the component location. While routing the traces, the clock
signal traces should be routed first and should be locked prior to
routing other signal traces.
All the resistors and capacitors are size 0603.
POWER
AND
GROUNDING
• The differential 50Ω output traces should have same
length.
Place the decoupling capacitors as close as possible to the power
pins. If space allows, placement of the decoupling capacitor on
the component side is preferred. This can reduce unwanted inductance between the decoupling capacitor and the power pin
caused by the via.
• Avoid sharp angles on the clock trace. Sharp angle
turns cause the characteristic impedance to change on
the transmission lines.
• Keep the clock traces on the same layer. Whenever possible, avoid placing vias on the clock traces. Placement
of vias on the traces can affect the trace characteristic
impedance and hence degrade signal integrity.
Maximize the power and ground pad sizes and number of vias
capacitors. This can reduce the inductance between the power
and ground planes and the component power and ground pins.
• To prevent cross talk, avoid routing other signal traces in
parallel with the clock traces. If running parallel traces is
unavoidable, allow a separation of at least three trace
widths between the differential clock trace and the other
signal trace.
The RC filter consisting of R7, C11, and C16 should be placed
as close to the VDDA pin as possible.
CLOCK TRACES
AND
TERMINATION
Poor signal integrity can degrade the system performance or
cause system failure. In synchronous high-speed digital systems,
the clock signal is less tolerant to poor signal integrity than other
signals. Any ringing on the rising or falling edge or excessive ring
back can cause system failure. The shape of the trace and the
• Make sure no other signal traces are routed between the
clock trace pair.
• The series termination resistors should be located as
close to the driver pins as possible.
50 Ohm
Trace
C3
VCC
R1
U1
VIA
R7
VCCA
GND
Pin 1
C11
C16
Other
signals
C2
R2
C1
50 Ohm
Trace
FIGURE 4B. PCB BOARD LAYOUT FOR ICS87931I
87931BYI
www.icst.com/products/hiperclocks.html
11
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
RELIABILITY INFORMATION
TABLE 8. θJAVS. AIR FLOW TABLE
qJA by Velocity (Linear Feet per Minute)
Single-Layer PCB, JEDEC Standard Test Boards
Multi-Layer PCB, JEDEC Standard Test Boards
0
200
500
67.8°C/W
47.9°C/W
55.9°C/W
42.1°C/W
50.1°C/W
39.4°C/W
NOTE: Most modern PCB designs use multi-layered boards. The data in the second row pertains to most designs.
TRANSISTOR COUNT
The transistor count for ICS87931I is: 2942
87931BYI
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12
REV. A JUNE 23, 2003
ICS87931I
Integrated
Circuit
Systems, Inc.
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
PACKAGE OUTLINE - Y SUFFIX
TABLE 9. PACKAGE DIMENSIONS
JEDEC VARIATION
ALL DIMENSIONS IN MILLIMETERS
BBA
SYMBOL
MINIMUM
NOMINAL
MAXIMUM
32
N
A
--
--
1.60
A1
0.05
--
0.15
A2
1.35
1.40
1.45
b
0.30
0.37
0.45
c
0.09
--
0.20
D
9.00 BASIC
D1
7.00 BASIC
D2
5.60 Ref.
E
9.00 BASIC
E1
7.00 BASIC
E2
5.60 Ref.
e
0.80 BASIC
L
0.45
0.60
0.75
q
0°
--
7°
ccc
--
--
0.10
Reference Document: JEDEC Publication 95, MS-026
87931BYI
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13
REV. A JUNE 23, 2003
Integrated
Circuit
Systems, Inc.
ICS87931I
LOW SKEW, 1-TO-6
LVCMOS/LVTTL CLOCK MULTIPLIER/ZERO DELAY BUFFER
TABLE 10. ORDERING INFORMATION
Part/Order Number
Marking
Package
Count
Temperature
ICS87931BYI
ICS87931BYIT
ICS87931BI
32 Lead LQFP
250 per tray
-40°C to 85°C
ICS87931BI
32 Lead LQFP on Tape and Reel
1000
-40°C to 85°C
While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems, Incorporated (ICS) assumes no responsibility for either its use or
for infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal
commercial and industrial applications. Any other applications such as those requiring high reliability or other extraordinary environmental requirements are not recommended without
additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices
or critical medical instruments.
87931BYI
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14
REV. A JUNE 23, 2003
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