PI6C557-03ALE

PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Features
Description
ÎÎPCIe® 2.0 compliant
The PI6C557-03A is a spread spectrum clock generator compliant to PCI Express® 2.0 and Ethernet requirements. The device is
used for PC or embedded systems to substantially reduce Electromagnetic Interference (EMI).
àà Phase jitter - 2.1ps RMS (typ)
ÎÎLVDS compatible outputs
ÎÎSupply voltage of 3.3V ±10%
ÎÎ25MHz crystal or clock input frequency
The PI6C557-03A provides two differential (HCSL) or LVDS
spread spectrum outputs. The PI6C557-03A is configured to select spread and clock selection. Using Pericom's patented PhaseLocked Loop (PLL) techniques, the device takes a 25MHz crystal
input and produces two pairs of differential outputs (HCSL) at
25MHz, 100MHz, 125MHz and 200MHz clock frequencies. It
also provides spread selection of -0.5%, -0.75%, and no spread.
ÎÎHCSL outputs, 0.8V Current mode differential pair
ÎÎJitter 35ps cycle-to-cycle (typ)
ÎÎSpread of -0.5%, -0.75%, and no spread
ÎÎIndustrial temperature range
ÎÎSpread Bypass option available
ÎÎSpread and frequency selection via external pins
ÎÎPackaging: (Pb-free and Green)
àà 16-pin TSSOP (L16)
àà 16-pin QSOP (Q16)
Pin Configuration (16-Pin TSSOP)
Block Diagram
VDD
2
SS1:SS0
S1:S0
2
Control
Logic
1
16
VDDX
S1
2
15
CLK0
SS0
3
14
CLK0
X1/CLK
4
13
GNDA
X2
5
12
VDDA
OE
6
11
CLK1
GNDX
7
10
CLK1
SS1
8
9
IREF
CLK1
X1/CLK
Pulling
Capacitors
S0
CLK0
Phase
Lock
Loop
2
25 MHz
crystal or clock X2
CLK0
CLK1
Crystal
Driver
2
GND
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RR
OE
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Pin Description
Pin # Pin Name
I/O Type
Description
1
S0
Input
Select pin 0 (Internal pull-up resistor). See Table 1.
2
S1
Input
Select pin 1 (Internal pull-up resistor). See Table 1.
3
SS0
Input
Spread Select pin 0 (Internal pull-up resistor). See Table 2.
4
X1/CLK
Input
Crystal or clock input. Connect to a 25MHz crystal or single ended clock.
5
X2
Output
Crystal connection. Leave unconnected for clock input.
6
OE
Input
Output enable. Internal pull-up resistor.
7
GNDX
Power
Crystal ground pin.
8
SS1
Input
Spread Select pin 1 (Internal pull-up resistor). See Table 2.
9
IREF
Output
Precision resistor attached to this pin is connected to the internal current reference.
10
CLK1
Output
HCSL compliment clock output
11
CLK1
Output
HCSL clock output
12
VDDA
Power
Connect to a +3.3V source.
13
GNDA
Power
Output and analog circuit ground.
14
CLK0
Output
HCSL compliment clock output
15
CLK0
Output
HCSL clock output
16
VDDX
Power
Connect to a +3.3V source.
Table 2: Spread Selection Table
Table 1: Output Frequency Select Table
S1
S0
CLK(MHz)
SS1
SS0
Spread
0
0
25
0
0
No Spread
0
1
100
0
1
Down -0.5
1
0
125
1
0
Down -0.75
1
1
200
1
1
No Spread
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Application Information
Output Structures
Decoupling Capacitors
Decoupling capacitors of 0.01μF should be connected between
each VDD pin and the ground plane and placed as close to the
VDD pin as possible.
IREF =2.3mA
6*IREF
Crystal
Use a 25MHz fundamental mode parallel resonant crystal with
less than 300PPM of error across temperature.
Crystal Capacitors
CL = Crystals's load capacitance in pF
Crystal Capacitors (pF) = (CL - 8) *2
R R=475 Ω
For example, for a crystal with 16pF load caps, the external effective crystal cap would be 16 pF. (16-8)*2=16.
See Output Termination
Sections
Current Source (IREF) Reference Resistor - R R
If board target trace impedance is 50Ω,
then R R = 475Ω providing an IREF of 2.32 mA. The output current (IOH) is 6*IREF.
Output Termination
The PCI Express differential clock outputs of the PI6C557-03A
are open source drivers and require an external series resistor
and a resistor to ground. These resistor values and their allowable locations are shown in detail in the PCI Express Layout
Guidelines section.
The PI6C557-03A can be configured for LVDS compatible voltage levels. See the LVDS Compatible Layout Guidelines section.
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
PCI Express Layout Guidelines
Common Recommendations for Differential Routing
Dimension or Value
Unit
L1 length, route as non-coupled 50Ω trace.
0.5 max
inch
L2 length, route as non-coupled 50Ω trace.
0.2 max
inch
L3 length, route as non-coupled 50Ω trace.
0.2 max
inch
RS
33
Ω
RT
49.9
Ω
Differential Routing on a Single PCB
Dimension or Value
Unit
L4 length, route as coupled microstrip 100Ω differential trace.
2 min to 16 max
inch
L4 length, route as coupled stripline 100Ω differential trace.
1.8 min to 14.4 max
inch
Differential Routing to a PCI Express connector
Dimension or Value
Unit
L4 length, route as coupled microstrip 100Ω differential trace.
0.25 min to 14 max
inch
L4 length, route as coupled stripline 100Ω differential trace.
0.225 min to 12.6 max
inch
PCI Express Device Routing
L1
L2
RS
L1’
L4
L4’
L2’
RS
RT
PI6C557-03A
Output
Clock
L3’
RT
PCI-Express
Load or
Connector
L3
Typical PCI Express (HCSL) Waveform
800 mV
0
tOR
250 ps
400 ps
0.52 V
0.175 V
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13-0052
tOF
0.52 V
0.175 V
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Application Information
LVDS Recommendations for Differential Routing
Dimension or Value
Unit
L1 length, route as non-coupled 50Ω trace.
0.5 max
inch
L2 length, route as non-coupled 50Ω trace.
0.2 max
inch
RP
100
Ω
RQ
100
Ω
RT
150
Ω
L3 length, route as 100Ω differential trace.
L3 length, route as 100Ω differential trace.
LVDS Device Routing
L1
RS
L1’
L4
L4’
L2’
RS
PI6C557-03A
Output
Clock
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L2
RT
L3’
13-0052
RT
L3
5
PCI-Express
Load or
Connector
www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Maximum Ratings
Note:
(Above which useful life may be impaired. For user guidelines, not tested.)
Stresses greater than those listed under 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.
Supply Voltage to Ground Potential . . . . . . . . . . . . . . . . . . . . . . . 5.5V
All Inputs and Outputs . . . . . . . . . . . . . . . . . . . . . -0.5V to VDD+0.5V
Ambient Operating Temperature . . . . . . . . . . . . . . . . . . . -40 to +85°C
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . -65 to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
Soldering Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C
ESD Protection (Input) . . . . . . . . . . . . . . . . . . . . . 2000 V min (HBM)
Electrical Specifications
Recommended Operation Conditions
Parameter
Min.
Ambient Operating Temperature
Power Supply Voltage (measured in respect to GND)
Typ.
Max.
Unit
-40
+85
°C
+3.0
+3.6
V
DC Characteristics (VDD = 3.3V ±10%, TA = -40°C to +85°C)
Symbol
Parameter
VDD
Supply Voltage
Voltage(1)
VIH
Input High
VIL
Input Low Voltage(1)
IIL
Input Leakage Current
Conditions
Min.
Typ.
Max.
Unit
3.0
3.3
3.6
V
OE
2.0
VDD +0.3
V
OE
GND -0.3
0.8
V
-20
20
0 < Vin < VDD
With input pull-up
and pull-downs
Without input pull-up
-5
and pull-downs
µA
5
R L = 50Ω, CL = 2pF
95
mA
IDDOE
Operating Supply Current
OE = LOW
50
mA
CIN
Input Capacitance
@ 55MHz
7
pF
COUT
Output Capacitance
@ 55MHz
6
pF
LPIN
Pin Inductance
5
nH
ROUT
Output Resistance
IDD
CLK Outputs
3.0
kΩ
Notes:
1. Single edge is monotonic when transitioning through region.
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
HCSL Output AC Characteristics (VDD = 3.3V ±10%, TA = -40°C to +85°C)
Symbol
Parameter
Conditions
Min.
Typ.
Max.
FIN
Input Frequency
VOUT
Output Frequency
VOH
Output High Voltage (1,2)
VOL
Output Low Voltage(1,2)
VCPA
Crossing Point Voltage(1,2)
Absolute
VCN
Crossing Point Voltage
Variation over all edges
JCC
Jitter, Cycle-to-Cycle(1,3)
JRMS
PCIe RMS Jitter
PCIe 2.0 Test Method @ 100MHz
Output
MF
Modulation Frequency
Spread Spectrum
30
tOR
Rise Time
From 0.175V to 0.525V
tOF
Fall Time(1,2)
From 0.525V to 0.175V
TSKEW
Skew between outputs
At Crossing Point Voltage
TDUTY-CYCLE
Duty Cycle(1,3)
TOE
Output Enable Time(5)
TOT
Output Disable Time
tSTABLE
From power-up to VDD =3.3V
From Power-up VDD =3.3V
3.0
ms
tSPREAD
Setting period after spread change
Setting period after spread change
3.0
ms
25
25
(1,2,4)
100 MHz HCSL output @ VDD =
3.3V
660
800
-150
0
250
350
200
MHz
900
mV
550
mV
140
mV
60
ps
3.1
ps
33
kHz
175
500
ps
175
500
ps
50
ps
55
%
All outputs
10
μs
All outputs
10
μs
31.5
45
(5)
MHz
mV
35
(1,2)
Unit
Notes:
1. RL = 50-Ohm with CL = 2 pF
2. Single-ended waveform
3. Differential waveform
4. Measured at the crossing point
5. CLK pins are tri-stated when OE is LOW
Thermal Characteristics
Symbol
Parameter
Conditions
θJA
Thermal Resistance Junction to Ambient
Still air
θJC
Thermal Resistance Junction to Case
Min.
Typ.
Max.
Unit
90
°C/W
24
°C/W
Recomended Crystal Specification
Pericom recommends:
a) GC2500003 XTAL 49S/SMD(4.0 mm), 25M, CL=18pF, +/-30ppm
http://www.pericom.com/pdf/datasheets/se/GC_GF.pdf
b) FY2500081, SMD 5x3.2(4P), 25M, CL=18pF, +/-30ppm
http://www.pericom.com/pdf/datasheets/se/FY_F9.pdf
c) FL2500047, SMD 3.2x2.5(4P), 25M, CL=18pF, +/-20ppm
http://www.pericom.com/pdf/datasheets/se/FL.pdf
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Packaging Mechanical: 16-Pin TSSOP (L)
Note: For latest package info, please check: http://www.pericom.com/products/packaging/mechanicals.php
All trademarks are property of their respective owners.
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www.pericom.comPI6C557-03A Rev.E
05/06/13
PI6C557-03A
PCIe 2.0 Clock Generator with 2 HCSL Outputs
Packaging Mechanical: 16-Pin QSOP (Q)
DOCUMENT CONTROL NO.
PD - 1201
REVISION: G
16
.008
0.20
MIN.
.150
.157
3.81
3.99
Guage Plane
.010
0.254
1
DATE: 11/07/07
.008
.013
0.20
0.33
Detail A
.189
.197
4.80
5.00
0˚-6˚
.016
.035
0.41
0.89
.041
1.04
REF
.015 x 45° 0.38
1
.008
0.203 REF
.053 1.35
.069 1.75
Detail A
.007
.010
0.178
0.254
SEATING
PLANE
.025
BSC
0.635
.008
.012
0.203
0.305
.228
.244
5.79
6.19
.004 0.101
.010 0.254
X.XX DENOTES DIMENSIONS IN MILLIMETERS
X.XX
Note:
1) Controlling dimensions in inches.
2) Ref: JEDEC MO-137B/AB.
3) Dimensions do not include mold flash, protrusions or gate burrs
Pericom Semiconductor Corporation
3545 N. 1st Street, San Jose, CA 95134
1-800-435-2335 • www.pericom.com
DESCRIPTION: 16-Pin 150-Mil Wide QSOP
PACKAGE CODE: Q
Note: For latest package info, please check: http://www.pericom.com/products/packaging/mechanicals.php
Ordering Information
Ordering Code
Package Code
Package Type
PI6C557-03ALE
L
Pb-free & Green, 16-pin TSSOP
PI6C557-03AQE
Q
Pb-free & Green, 16-pin QSOP
Notes:
• Thermal characteristics can be found on the company web site at www.pericom.com/packaging/
• "E" denotes Pb-free and Green
• Adding an "X" at the end of the ordering code denotes tape and reel packaging
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05/06/13