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chris.heard100@gmail.com. 603-494-9277www.cshconsulting.net 1

PCB Routing Guidelines for Signal Integrity

and Power Integrity

November 18, 2015

Presentation by Chris Heard

Orange County chapter meeting

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Agenda

• Insertion Loss 101• PCB Design Guidelines For SI• Simulation Examples and Tools• Power Integrity Examples

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Insertion Loss 101

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What is Insertion Loss?

Insertion loss is the loss of signal amplitude resulting from the insertion of a device in a transmission line and is expressed in decibels (dB)

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Datarate and Fundamental Frequency

200pS

The 10Gbps Signal

100pSDatarate = 10Gbps = 10e9

Time Between Crossings = 1 / 10e9

Period of Sinusoid = 200pSFrequency of Sinusoid = 1 / 200pS = 5e9

The “Fundamental Frequency ” = 5e9 = 5GHzAlso called the “Nyquist Frequency”

Sinusoid

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10Gbps Example

How much insertion loss does this path have?20 * log (0.1 / 1.0) = -20dB of Insertion Loss (at 5GHz)

1V

0.1V100pS

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Voltage vs Material in Volts

0.00

0.20

0.40

0.60

0.80

1.00

1.20

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 22.0 24.0 26.0 28.0 30.0 32.0 34.0 36.0 38.0 40.0

Volts

Frequency (GHz)

FR4 Hight Tg Nelco 4000-13 Megtron-6

FR4: 0.1VMeg6: 0.4V(4x better)

FR4

Nelco 4000-13

Megtron-6

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Loss vs Material in dB

-20.0 dB

5.0 GHz

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 22.0 24.0 26.0 28.0 30.0 32.0 34.0 36.0 38.0 40.0

Loss

(dB

)

Frequency (GHz)

Loss vs FrequencyFR4 High Tg Nelco 4000-13 Megtron-6

FR4: -20dBMeg6: -8dB(12dB better)

FR4 Nelco 4000-13

Megtron-6

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PCB Design Guidelines For SI

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Routing Through Antipads

Do Not Rout traces by antipads without any overhang.

Ensure 3.0mil of Ground plane overhang when routing through Antipads. 3.0mil

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Joining Antipads: 1

Do not join Antipad Voids together.

Separate the via pairs so that the antipad voids do not join.

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P N P

Joining Antipads: 2IPASS Connector

In this case the space between P and N signals is larger than the space to the next pair. This will increase crosstalk between pairs.

Arrange pins in a G-S-S-G format. Use the ground pins to achieve isolation between diff pairs.

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Antipads too Close

Antipads too close causing no ground plane for diff pair.

Reduced size of antipad allows for adequate ground plane overhang

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Skew Compensation: 1

This method of increasing length causes crosstalk and impedance issues for any signal over 500MHz

Lengthen Trace within the antipad region as shown.

Trace can connect to pad at these locations. Keep lengthened trace within the antipad opening.

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Skew Compensation: 2

At least 50 mil separation to reduce coupling between jogs.

4.35 mil trace to maintain impedance.

4.35 mil trace to maintain impedance.

4.25 mil normal trace width

10 mils

8.75 mil space

This is the recommended approach

The wider trace widths need to be calculated with a field solver for each application.

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Transition Vias Without Grounds

No Ground Vias for the diff pair.

Ground vias added as described in pre-layout simulation results.

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Transition Vias: Proper Design

0

0 1 2 3

Oval Dogbone 40.0mil

Antipad Dia 40.0mil

Pad Dia 20.0mil

Drill Dia 9.8mil

Finished Dia 8.0mil

Line Space 6.70mil

EtchBack 0.1mil

Line Width 6mil

Layer Escape 6

Diff Port Zo 100

Thickness 91.7 mil

Layers 8

Df 0.01

Dk 3.9

Material RogersTheta

Units mm

Antipad Dia 40.0mil

GND Via GND Via

Ground Vias are spaced properly. Antipads and Drill sizes are specified.

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Drill Size Versus Finished SizePad Stack Drill Diameter shows the Finished Diameter.

Fab Drawing attempts to correct the problem by stating what drill size to use

Drill size in PCB Design Padstack should match Drill size desired. It’s not OK to allow the PCB Fabricator to pick a drill size.

Signal Integrity Tools import the Drill Size from the Padstack, making simulation results look better than they actually are.

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Specify Drill Size for Transition Vias and AC Caps

Drill Chart doesn’t specify the drill size, but the finished size only

Drill size matches actual drill availability. Tolerance allows to be plated shut. Note 12 calls out the drill size.

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Reliefs Under AC Caps

Add a relief under AC Capacitors on the adjacent ground plane to increase impedance for 0402 Caps on 1mm pitch

Cap Pads 21 x 18

L2 Clearance 25 x 60

1

2

Relief can be individual rectangles or a full rectangle encompassing both capacitors.

Either way it must be simulated and verified. It is stackup and material dependent!

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SMT Pad Transitions

No Ground Vias for the diff pair. No clearance under pads.

Ground vias added as described in pre-layout simulation results.

Clearance under pads on adjacent plane layer only, increase impedance for a better match to 100ohms

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Thermal Reliefs on Press Fit Connectors

Do Not use Thermal Reliefs on Press Fit Connectors.

Change Thermal Reliefs to Direct Connections to the plane.

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Rectangular or Oval Antipads on High Speed Connectors

Do Not use simple round antipads on high speed connectors

(Example: AirMax)

Change to rectangular or oval shape described in pre-layout simulation results.

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Routing Over Ground Plane Edges

Do Not Rout Over and Ground Plane Edge

Move the etch away from the ground plane edge or increase the size of the ground plane edge. Diff pa ir should be >30mil (8H) from edge of plane.

H=Distance from Signal Layer to reference plane layer

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Diff Pairs Not Centered in Routing Channels

Diff pairs running over antipad edges

Diff pair centered in the channel.

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Diff Pairs Spaced Too Close

6-9-6 diff pair spaced 10mils apart. Needs 25-30mils of spacing (4H).

Diff pairs spaced by 30mils

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Take Advantage of “Unused” Ground Planes

Move diff pairs up to adjacent channel to avoid the nearby Tx pair and to make use of a better ground reference.

Diff pairs moved away from nearby oval antipads to minimize coupling to other BGA signal pads.

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Diff Pair Spacing on Top and Bottom Layers

Microstrip surface pairs are 12mil between P and N. Diff pairs are spaced 16mil apart. This causes lots of crosstalk.

They need to be 50-75mil apart! (10H)

Move diff pairs to inner layers and use closer spacing between P and N (8mil).

Or use 50-75mil spacing between pairs on the surface.

12.0mil

16.0mil

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Splitting Up Diff Pairs: 1

Avoid separating diff pairs to get around vias.

Keep the pair coupled together at all times.

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Splitting Up Diff Pairs: 2

Avoid separating diff pairs to get around vias.

3-4-3 : 102 ohms

3-21-3: 112 ohms

Keep the pair coupled together at all times. Widen the line in areas where the lines pull apart.

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Serpentine Spacing

Serpentines are 13mils apart.

Diff pairs are 8.75mils apart.

This causes about 0.2% of crosstalk on to itself, which is too high.

Increase spacing to 17mils or more (4H)

H=Distance from Signal Layer to reference plane lay er

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Haphazard Ground Via Locations

Ground Vias are positioned randomly.

Ground Vias placed matching pre-layout simulations

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Floating Ground Islands on Signal Layers

Gnd Etch added to signal layer and connected only at the ends with vias.

This is an attempt to lower crosstalk.

Remove all Ground Islands on signals layers. By the time the island is added, the traces are far enough apart anyway.

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Routing Over Splits: 1

Traces crossing over a split in the ground plane on an adjacent layer

Remove the split in the ground plane or move the traces to a layer that has a continuous plane.

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Routing Over Splits: 2

DQS DDR3 signal runs down the split in the plane shown in red box.

Remove the split in the ground plane or move the traces to a layer that has a continuous plane.

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Blind Vias: Antipads Too Large. Example 1

DQ signals running over massive voids on Layer 2 due to blind via connections.

Alternate the use of standard through holes with Blind Vias.

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Blind Vias: Antipads Too Large. Example 20.8mm ball pitch

Large Joined Voids present on L5, 7,9,12,14,16.

All traces in this area will couple together.

Signals on L6,8,10,11,13, 15 all couple together

Alternate the use of standard through holes with Blind Vias.

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Blind Vias: Out of Control Signal Paths

Red and Yellow signal paths are not coupled or consistent.

Ground Vias provide no isolation between signal vias throughout the board because they are Blind vias from L1-L3

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Copper Utilization

Traces are routed at minimum spacing with tons of copper available on either side.

Spread Traces out to take advantage of the unused c opper and reduce crosstalk in the process

Use these unused areas

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Backdrilling at 6Gbps

Long stubs under connecting layers cause resonance.

Backdrill to multiple depths keeping stubs less than 30mils (at 6Gbps)

SIG 2.13.35

PLANE 1.33.50

SIG 0.654.45

PLANE 0.653.50

SIG 0.654.45

PLANE 0.653.50

SIG 0.654.45

PLANE 0.653.50

PLANE 0.652.70

PLANE 0.653.00

PLANE 0.652.70

PLANE 0.653.00

PLANE 0.652.70

PLANE 0.653.00

PLANE 0.654.45

SIG 0.653.50

PLANE 0.654.45

SIG 0.653.50

PLANE 0.654.45

SIG 0.653.50

PLANE 1.33.35

SIG 2.1

Top to L3 with backdrilling

Top to L5 with backdrilling

Top to L7 with backdrilling

Top to L16 with backdrilling

Top to L18, no backdrilling

Top to L20, no backdrilling

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Simulation Examples and Tools

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Channel Modeling - Process and Tools

• Channel Models created in Hspice Or ADS–S-parameters of connector, footprint, etch

• Connector Models–Provided by Connector Vendor in Touchstone format.

• PCB Footprints / Via Models–Simulated in Ansoft HFSS

• PCB Etch Models–De-Embedded S-parameter Model generated in HFSS

BGA Package

BGA Via

PCB Etch

Via Via Connector Via

BackplanePCB Etch

PCB Etch

AC Cap

Via ViaConnectorBGA

Package

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Statistical Eye: 6.25GbpsMeasurement vs. Simulation

Measurement

Simulation (from LinkEye)

240mV0.76UI

162mV0.70UI

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ADS Schematic:1 Million Bit-By-Bit Simulation

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Statistical Eye: 12.5Gbps1 Million Bit-By-Bit Simulation

Amplitude: 336mVWidth: 63psWidth: 0.79UI

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Via Model Example: Return Loss Improvements

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Via Model: Transition Via As Designed

Oval Dogbone 20.0mil

Antipad Dia 34.0mil

Pad Dia 18.0mil

Drill Dia 11.7mil

Finished Dia 8.0mil

Line Space 8.0mil

EtchBack 0.1mil

Line Width 3.50mil

Layer Escape 1 and 5

Diff Port Zo 100

Thickness 61.5 mil

Layers 14

Df 0.008

Dk 3.5

Material EM888

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Via Model: Transition Via Modified

Oval Dogbone 35.0mil

Antipad Dia 45.0mil

Pad Dia 18.0mil

Drill Dia 11.7mil

Finished Dia 8.0mil

Backdrill Hole? Yes

Backdrill Dia 20.0mil

Default Stub 20.0mil

Line Space 8.0mil

EtchBack 0.1mil

Line Width 3.50mil

Layer Escape 1 and 5

Diff Port Zo 100

Thickness 61.5 mil

Layers 14

Df 0.008

Dk 3.5

Material EM888

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0 2 4 6 8 10 12 14 16 18 20-40

-35

-30

-25

-20

-15

-10

-5

0Differential Insertion and Return Loss: SEB1-TransVia

Frequency (GHz)

Mag

nitu

de (

dB)

sdd12

sdd11

IL, RL and TDR: Transition Via As Designed

-16dB at 5.0GHz.

Marginal

TDR: SEB1-TransVia

65

70

75

80

85

90

95

100

105

110

0 0.05 0.1 0.15 0.2 0.25 0.3

Time(nS)

Simulated Differential TDR

Ohm

s

75 ohms.

Goal

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0 2 4 6 8 10 12 14 16 18 20-40

-35

-30

-25

-20

-15

-10

-5

0Differential Insertion and Return Loss: SEB1-TransVia-R1

Frequency (GHz)

Mag

nitu

de (

dB)

sdd12

sdd11

IL, RL and TDR: Transition Via Modified

-38dB at 5.0GHz.

Excellent

TDR: SEB1-TransVia-R1

65

70

75

80

85

90

95

100

105

110

0 0.05 0.1 0.15 0.2 0.25 0.3

Time(nS)

Simulated Differential TDR

Ohm

s

95 ohms.Goal

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Via Model: 0.8mm BGA

Antipad Dia 26.0mil

Pad Dia 18.0mil

Drill Dia 9.8mil

Finished Dia 6.0mil

Line Space 4.6mil

EtchBack 0.1mil

Line Width 3.45mil

Layer Escape 10

Diff Port Zo 100

Thickness 98.0 mil

Layers 14

Df 0.0147

Dk 3.86

Material FR408HR

Adapt Freq. 10 GHz

Max Freq. 20 GHz

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Via Model: 0.8mm BGA -R1With 32/30 Antipad and 22mil clearance under BGA Pa ds

Oval Dogbone 30.0mil

Antipad Dia 32.0mil

Pad Dia 18.0mil

Drill Dia 9.8mil

Finished Dia 6.0mil

Line Space 31.5mil

EtchBack 0.1mil

Line Width 3.45mil

Layer Escape 10

Diff Port Zo 100

Thickness 98.0 mil

Layers 14

Df 0.0147

Dk 3.86

Material FR408HR

Adapt Freq. 10 GHz

Max Freq. 20 GHz

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IL, RL and TDR: 0.8mm BGA

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20-40

-35

-30

-25

-20

-15

-10

-5

0

Frequency (GHz)

Mag

nitu

de (

dB)

Differential Insertion and Return Loss: U26 BGA L10 Out TTM

-13.3dB @ 5.0GHz

Sdd12Sdd11Goal

0 0.1 0.2 0.3 0.475

80

85

90

95

100

105

Time (nS)

Ohm

s

78.1 to 100.1 ohms

TDR: U26-BGA-L10-Out-TTM

U26-BGA-L10-Out-TTM

This is not acceptable performance at 10Gbps

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IL, RL and TDR: 0.8mm BGA -R1With 32/30 Antipad and 22mil clearance under BGA Pa ds

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20-40

-35

-30

-25

-20

-15

-10

-5

0

Frequency (GHz)

Mag

nitu

de (

dB)

Differential Insertion and Return Loss: U26 BGA L10 Out R1 TTM

-18.5dB @ 5.0GHz

Sdd12Sdd11Goal

0 0.1 0.2 0.3 0.475

80

85

90

95

100

105

Time (nS)

Ohm

s

86.5 to 100.4 ohms

TDR: U26-BGA-L10-Out-R1-TTM

U26-BGA-L10-Out-R1-TTM

This is acceptable.

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Via Model Example: Alternating Layers

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Via Model: BGA -L14

Oval Dogbone 30.0mil

Antipad Dia 30.0mil

Pad Dia 20.0mil

Drill Dia 9.8mil

Finished Dia 6.0mil

Line Space 6.0mil

EtchBack 0.1mil

Line Width 3.90mil

Layer Escape 14

Diff Port Zo 95

Thickness 76.0 mil

Layers 16

Df 0.011

Dk 3.35

Material N4000-13-SI

Adapt Freq. 20 GHz

Max Freq. 40 GHz

Rx (Victim )

Rx1Layer 14

Layer 14

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Via Model: BGA -L14-R1Alternate layer assignments

Oval Dogbone 30.0mil

Antipad Dia 30.0mil

Pad Dia 20.0mil

Drill Dia 9.8mil

Finished Dia 6.0mil

Backdrill Hole? Yes

Backdrill Dia 20.0mil

Default Stub 20.0mil

Line Space 6.0mil

EtchBack 0.1mil

Line Width 3.90mil

Layer Escape 3 and 14

Diff Port Zo 95

Thickness 76.0 mil

Layers 16

Df 0.011

Dk 3.35

Material N4000-13-SI

Adapt Freq. 20 GHz

Max Freq. 40 GHz

Rx (Victim )

Rx1Layer 14

Layer 3

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IL, RL and TDR: BGA L14

0 5 10 15 20 25 30 35 40-40

-35

-30

-25

-20

-15

-10

-5

0Differential Insertion and Return Loss: U131 BGA L14

-18.7dB @ 7.0GHz

Frequency (GHz)

Mag

nitu

de (

dB)

Sdd12Sdd11Goal

0 0.1 0.2 0.3 0.470

75

80

85

90

95

100

105

110

Time (nS)

Ohm

s

83.2 to 95.7 ohms

TDR: U131-BGA-L14

U131-BGA-L14

Bottom Layer Has Great Return Loss

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IL, RL and TDR: BGA L14 R1

0 5 10 15 20 25 30 35 40-40

-35

-30

-25

-20

-15

-10

-5

0Differential Insertion and Return Loss: U131 BGA L14 R1

-15.9dB @ 7.0GHz

Frequency (GHz)

Mag

nitu

de (

dB)

Sdd12Sdd11Goal

0 0.1 0.2 0.3 0.470

75

80

85

90

95

100

105

110

Time (nS)

Ohm

s

77.9 to 95.3 ohms

TDR: U131-BGA-L14-R1

U131-BGA-L14-R1

Layer 3 with Backdrilled Stub a Lower Impedance

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Next and Fext: BGA L14

0 5 10 15 20 25 30 35 40-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0Next Crosstalk Contributors: U131 BGA L14

-28.4dB @ 7.0GHz

Next1= 1,3.

Frequency (GHz)

Mag

nitu

de (

dB)

Next1Goal

0 5 10 15 20 25 30 35 40-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0Fext Crosstalk Contributors: U131 BGA L14

-27.2dB @ 7.0GHz

Fext1= 1,4.

Frequency (GHz)

Mag

nitu

de (

dB)

Fext1Goal

Crosstalk between the Vias is high.

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Next and Fext: BGA L14 R1

0 5 10 15 20 25 30 35 40-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0Next Crosstalk Contributors: U131 BGA L14 R1

-33.9dB @ 7.0GHz

Next1= 1,3.

Frequency (GHz)

Mag

nitu

de (

dB)

Next1Goal

0 5 10 15 20 25 30 35 40-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0Fext Crosstalk Contributors: U131 BGA L14 R1

-36.1dB @ 7.0GHz

Fext1= 1,4.

Frequency (GHz)

Mag

nitu

de (

dB)

Fext1Goal

9dB (2.8x) Reduction in FEXT

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Via Model Example: Very Low Crosstalk

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Via Model: Amphenol XCedeHDPlus

AntiPad Width 70.0mil

AntiPad Height 44.0mil

Pad Dia 30.0mil

Drill Dia 17.7mil

Finished Dia 14.2mil

Backdrill Hole? Yes

Backdrill Dia 29.2mil

Default Stub 14.2mil

Line Space 9.8mil

EtchBack 0.1mil

Line Width 5.25mil

Layer Escape 20

Diff Port Zo 100

Thickness 126.1 mil

Layers 26

Df 0.0067

Dk 3.2

Material MyMeg6

Adapt Freq. 20 GHz

Max Freq. 40 GHz

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IL, RL and TDR: Amphenol XCedeHDPlus

0 5 10 15 20 25 30 35 40-60

-50

-40

-30

-20

-10

0Differential Insertion and Return Loss: Sim0481-XCedeHDPlus-DC-L20-ShimRiser

-14.8dB @ 12.5GHz

Frequency (GHz)

Mag

nitu

de (

dB)

Sdd12Sdd11Goal

0 0.1 0.2 0.3 0.480

85

90

95

100

105

110

Time (nS)

Ohm

s

86.5 to 101.3 ohms

TDR: Sim0481-XCedeHDPlus-DC-L20-ShimRiser

Sim0481-XCedeHDPlus-DC-L20-ShimRiser

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Next and Fext: Amphenol XCedeHDPlus

0 5 10 15 20 25 30 35 40-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0Next Crosstalk Contributors: Sim0481-XCedeHDPlus-DC-L20-ShimRiser

-55.2dB @ 12.5GHz

Next1= 1,3. Next2= 1,7. Next3= 1,5. Next4= 3,5.

Frequency (GHz)

Mag

nitu

de (

dB)

Next1Next2

Next3Next4Goal

0 5 10 15 20 25 30 35 40-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

0Fext Crosstalk Contributors: Sim0481-XCedeHDPlus-DC-L20-ShimRiser

-51.7dB @ 12.5GHz

Fext1= 1,4. Fext2= 1,8. Fext3= 1,6. Fext4= 3,6.

Frequency (GHz)

Mag

nitu

de (

dB)

Fext1Fext2

Fext3Fext4Goal

6.2x Lower than BGA Alternating Layer Example

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Etch Model Example: Mitre vs. Curved vs. Right Angle

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Straight Etch and Mitred Bend

1.0” long, 6mil line, 9 mil space

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Curved Bend and Right Angle Bend

1.0” long, 6mil line, 9 mil space

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0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20-3

-2.75

-2.5

-2.25

-2

-1.75

-1.5

-1.25

-1

-0.75

-0.5

-0.25

0Insertion Loss-Curved Trace Study

Frequency (GHz)

Mag

nitu

de (

dB)

Sdd12-StraightSdd12-MitredSdd12-Curved

Sdd12-Right Angle

Insertion Loss Comparison

Rt. Angle (worst)

Straight (best)

Mitred and Curved

•Higher is better in this chart.

•After about 8GHz, the right angle bend is worse than the others.

•Mitred and Curved are about the same all the way out to 20GHz.

•Straight is best at all frequencies

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0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20-40

-39

-38

-37

-36-35

-34

-33

-32

-31-30

-29

-28

-27

-26

-25-24

-23

-22

-21

-20-19

-18

-17

-16-15

Return Loss-Curved Trace Study

Frequency (GHz)

Mag

nitu

de (

dB)

Sdd11-MitredSdd11-CurvedSdd11-Right Angle

Return Loss Comparison

Rt. Angle

Curved

Mitred

Rt. Angle

Curved

Mitred

•Lower is better in this chart.

•After about 7GHz, the Right Angle bend is worse.

•Mitred and Curved are about the same all the way out to 15GHz

•Anything under -25dB is considered great!

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0 0.1 0.2 0.3 0.4 0.5 0.697

98

99

100

101

102

103Time Domain Wave Form

Time (nS)

Ohm

s

Right Angle

MitredCurved

TDR Comparison

Rt. Angle

Curved

Mitred

•Flatter is better in this chart.

•The Right Angle bend can be seen very clearly with the ~98ohm dip.

•The Curved and Mitred have very much the same TDR profile.

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Power Integrity Example 1

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Example CPU CORE VOLTAGE Layout

Input Power Inductor at 0.86V

Assume a Total of 4 Amps DC evenly distributed at all the CPU CORE VOLTAGE pins at the device.

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Stackup: With FaradFlex Embedded Capacitor Layers

Thickness Over Copper = 40.5 mils

Thickness Over Soldermask = 42.1 mils

1

Width Space Zo (ohms)

SIG 3.60 mil 5.90 mil 96.7

5.40 mil 49.9

2

3.20 Dk= 4.01

2 GND 0.6

4.50 Dk= 4.41

3 SIG 3.40 mil 8.60 mil 99.4

4.20 mil 48.2

0.6

4.60 Dk= 4.39

4 GND 0.60.90 FaradFlex. Dk=4.6

5 0.8V 1.3

3.90 TU-862 HF

6 0.8V 1.30.90

7 GND 0.6

4.60 Dk= 4.39

8 SIG 3.40 mil 8.60 mil 95.4

5.40 mil 49.9

0.6

4.50 Dk= 4.41

9 GND 0.6

3.20 Dk= 4.01

10 SIG 3.60 mil 5.90 mil 96.02

FaradFlex. Dk=4.6

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Stackup: Without FaradFlex

Thickness Over Copper = 47.7 mils

Thickness Over Soldermask = 49.3 mils

1

Width Space Zo (ohms)

SIG 3.60 mil 5.90 mil 96.7

5.40 mil 49.9

2

3.20 Dk= 4.01

2 GND 0.6

4.50 Dk= 4.41

3 SIG 3.40 mil 8.60 mil 99.4

4.20 mil 48.2

0.6

4.60 Dk= 4.39

4 GND 0.6

4.50 Dk= 4.39

5 0.8V 1.3

3.90 TU-862 HF

6 0.8V 1.3

4.50 Dk= 4.39

7 GND 0.6

4.60 Dk= 4.39

8 SIG 3.40 mil 8.60 mil 95.4

5.40 mil 49.9

0.6

4.50 Dk= 4.41

9 GND 0.6

3.20 Dk= 4.01

10 SIG 3.60 mil 5.90 mil 96.02

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CPU CORE VOLTAGE: Active CapsCap Value (uF) Quantity

0.01 110.1 71.0 310 147 5

Totals 27

Part Number RefDes Capacitance (F) Parasitic L (H) Parasitic R (ohms)

EMK105BJ104 C618 1.00E-07 4.30E-10 0.0144259

EMK105BJ104 C705 1.00E-07 4.30E-10 0.0144259

JMK105F105 C706 1.00E-06 1.71E-10 0.0023298

EMK105BJ104 C727 1.00E-07 4.30E-10 0.0144259

EMK105BJ104 C739 1.00E-07 4.30E-10 0.0144259

EMK105BJ104 C743 1.00E-07 4.30E-10 0.0144259

JMK105F105 C744 1.00E-06 1.71E-10 0.0023298

JMK105F105 C748a 1.00E-06 1.71E-10 0.0023298

EMK105BJ104 C752 1.00E-07 4.30E-10 0.0144259

CL21A476MQMNRN C758 4.70E-05 5.97E-10 0.00247449

CL21A476MQMNRN C762 4.70E-05 5.97E-10 0.00247449

C0603C106K9PAC C768 1.00E-05 7.86E-10 0.00390001

CL21A476MQMNRN C1603 4.70E-05 5.97E-10 0.00247449

CL21A476MQMNRN C1604 4.70E-05 5.97E-10 0.00247449

EMK105BJ104 C1606 1.00E-07 4.30E-10 0.0144259

CL21A476MQMNRN C1607 4.70E-05 5.97E-10 0.00247449

TMK105BJ103 C1927 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1928 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1929 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1930 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1931 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1952 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1953 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1954 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1955 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1956 1.00E-08 4.70E-10 0.0317317

TMK105BJ103 C1957 1.00E-08 4.70E-10 0.0317317

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CPU CORE VOLTAGE Plane SI Wave Import

IC200 Port

Current Sinks& Caps

Voltage Source (0.86v,

0.001ohm) & Caps

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Capacitor Plots

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0.001 0.01 0.1 1 10 100 10000.001

0.01

0.1

1

10

100

1000

10000

100000

1e+006

Frequency (MHz)

Impe

danc

e (o

hms)

Power Plane Impedance at IC200. Files: Toshiba KVDRIVE 1007 AO1 FaradFlex AC PlaneOnlyToshiba KVDRIVE 1007 AO1 FaradFlex AC PlaneandCaps

Goal: 0.021ohm @ 100.0MHz.

Plane Only

Plane With CapsGoal

Example CPU CORE VOLTAGE: Zo vs Freq With Faradflex Layers

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0.001 0.01 0.1 1 10 100 10000.001

0.01

0.1

1

10

100

1000

10000

100000

1e+006

Frequency (MHz)

Impe

danc

e (o

hms)

Goal: 0.021ohm @ 100.0MHz.

Plane Only

Plane With CapsGoal

Example CPU CORE VOLTAGE: Zo vs Freq With Faradflex Layers and No 0.01uF Caps

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0.001 0.01 0.1 1 10 100 10000.001

0.01

0.1

1

10

100

1000

10000

100000

1e+006

Frequency (MHz)

Impe

danc

e (o

hms)

Goal: 0.021ohm @ 100.0MHz.

Plane Only

Plane With CapsGoal

Example CPU CORE VOLTAGE: Zo vs Freq Without Faradflex Layers

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Example CPU CORE VOLTAGE Current Plot

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Layer 6 Example CPU CORE VOLTAGE Voltage Plot:IR Drop: 1.5mV, 4A. 0.375m Ω

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Layer 7 Voltage Plot: GND IR Drop: 0.681mV

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Power Integrity Example 2

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78 amps total.

Backplane 12V Current

6A At Each Power Connector

12V Connectors from Power Supply

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Voltage Plot. Gnd Plane: 15mV Total

15mV Drop

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Voltage Plot: +12V Plane: 80mV Total

80mV Drop

64.0A

0.58A

13.3A

12.0V

11.92V

Too High

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+12V Current Density

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