the main factors of pcb … · 2013-10-24 · attenuation, transmission loss, loss tangent (df),...
TRANSCRIPT
Journal of the HKPCA / Issue No. 50 / 2013/ Q412
Technical Paper
PCB
(Stripline)
(Df) (Rz)
(Test
Coupon or Vehicle)
(Df)
(Rz)
PCBPCB
The main factors of PCB AttenuationThe main factors of PCB Attenuation
Vic WONG / TTM Technologies - Dongguan Meadville Circuits Limited/ -
PCB
The main factors of PCB Attenuation
Abstract:
Key words:
PCB's attenuation sometimes was called
transmission loss or insertion loss (S21) as well.
This article has summarized the main factors of
attenuation of PCB's stripline structure based on
the exper iments: t ransmiss ion l ine length ,
laminate's loss tangent (Df), copper foil's surface
roughness (Rz), line width, backdrill and via stub.
According to customer's stackup, a test coupon or
vehicle with different parameters' combination can
be adjusted and tried, and then a good attenuation
product can be achieved.
Attenuation, Transmission Loss, Loss
Tangent (Df), Surface Roughness (Rz), Resin
Content, Skin Effect, Skin Depth, Line width,
Backdrill and via stub
( 1)
( )
1 Intel
PCB
2.1
Attenuation or Transmission Loss
(dB)
dB/m
(VNA: Vector Networks Analyzer 2) 3
PCB H OZ 155mm 90 m
(
GHz 0.4Ghz) (dB
) 3
PCB
( 4)
PCB
dB/m
µ
2.2
13www.hkpca.org
Technical Paper
2.3 (Df)
3 5 (Stripline
)
( Panasonic R-1755V R-5725)
VNA 6
2 Agilent N5247A
3 PCB HOZ 155mm 90um
4
R-1755V
R-5725
Df SPP (Short Pulse
Propagation technique)
1GHz (Df) 0.023 0.008
(Skin
Effect) ( 7)
(Skin
Depth) 7
(Df)
2.4 (Rz)
5 Stripline
6 Panasonic R-1755V R-5725
Journal of the HKPCA / Issue No. 50 / 2013/ Q414
Technical Paper
7 (ac) (
)
100MHz
7 m 10,000MHz (10GHz)
1 m
(Rz)
(Standard Foil) 7~8 m VLP (very Low
Prof ile) 3~5 m
100MHz
9 1 OZ 6mil
(Ra Rz
Ra Rz )
µ
µ
µ
µ
2.5 (Line width)
Stripline ( 10) 1 OZ
4.3+/-1 mil
4.3mil
0.4mil 4.7mil
1
35 0.4mil
3.5% ( 11)
8
9
10 Stripline
11
2.6 (Backdrill)
(via stub)
Broadside-Coupled Stripline
( 12 Broadside)
7 L5_L6 L8_L9
L 1 1 _ L 1 2 L 1 5 _ L 1 6 L 1 8 _ L 1 9 L 2 1 _ L 2 2
L24_L25 via
stub 7
(SDD21) 13 26
5.7mm Test pads L1
stub stub
stub
via stub
(Resonance) stub
7 (L26)
( 15) 14
via stub
12 Broadside-Coupled Stripline
13 7 Broadside stub
14 (
L25 ( ) L22 L19 L16 L12 L9 L6)
15 7 Broadside
3.1
PCB
(Stripline)
dB/m dB/in
dB
15www.hkpca.org
Technical Paper
Journal of the HKPCA / Issue No. 50 / 2013/ Q416
Technical Paper
3.2 (Df)
3.3 (Rz Ra)
3.4 (Line width)
3.5 (Backdrill) (via stub)
(Df)
(Resin Content)
Df
PCB
PCB
PCB
stub
(backplanes)
1.
PCB
PCB (Optical
PCB) PCB
Ra Rz
1. Ra: (arithmetical mean
deviation of the assessed prof ile)
Ra
Z Ra Ra
Ra
Ra
Ra 0.025~6.3 mµ
2. Rz (maximum height of prof ile)
Rz 5
5
[1] D r. E r i c B o g a t i n < S i g n a l I n t e g r i t y > ,
http://www.bethesignal.net/bogatin/
[2] IPC-TM-650 2.2.17A, Surface Roughness and
Prof ile of Metallic Foils (Contacting Stylus
Technique)
[3] P o l a r C I T S 8 0 0 s U s u a l M a n u a l ,
http://www.polarinstruments.com
[4] Intel SET2DIL: Method to Derive Differential
Insertion Loss from Single-Ended TDR/TDT
Measurements, Jeff Loyer, Intel Corp.
[5] Agilent Network Analyzer Basics
[6] IPC-TM-650 2.5.5 .12, Test methods to
Determine the Amount of Signal Loss on
Printed Boards (PBs)