Electrical Performance Report 85 ohm Reference Impedance

Electrical Performance Report
85 ohm Reference Impedance
ERM8-050-09.0-S-DV
Mates with
ERF8-050-07.0-S-DV
Description:
Edge Rate Strip Series, 0.8mm Centerline
16mm Stack Height
Samtec Inc.
520 Park East Blvd.
New Albany IN 47151-1147 USA
©Samtec, Inc. 2005
WWW.SAMTEC.COM
1-800-SAMTEC-9 (US & Canada)
[email protected]
Phone: 812-944-6733
Fax: 812-948-5047
Report Revision: 3/3/2009
All Rights Reserved
Electrical Performance Report
85 ohm Reference Impedance
Series: ERM8/ERF8 Edge Rate Strip Series
Description: 0.8mm (.0315”) Pitch, 16mm (0.630”) Stack Height
TABLE OF CONTENTS
Connector Overview........................................................................................................ 1
Purpose........................................................................................................................... 1
Differential Return Loss................................................................................................... 2
Differential Insertion Loss................................................................................................ 3
Differential Impedance Profile ......................................................................................... 4
Samtec Inc.
520 Park East Blvd.
New Albany IN 47151-1147 USA
©Samtec, Inc. 2005
WWW.SAMTEC.COM
1-800-SAMTEC-9 (US & Canada)
[email protected]
Page:ii
Phone: 812-944-6733
Fax: 812-948-5047
Report Revision: 2-6-2009
All Rights Reserved
Electrical Performance Report
85 ohm Reference Impedance
Series: ERM8/ERF8 Edge Rate Strip Series
Description: 0.8mm (.0315”) Pitch, 16mm (0.630”) Stack Height
Connector Overview
Edge Rate Strip Series 0.8mm (.0315”) pitch interfaces (ERF8/ERM8 Series) are available in
increments of 10 positions per row from 10 up to 70. Seventy-five positions per row are also
available. ERF8/ERM8 series board-to-board spacing is available in 7mm (0.2755”), 10mm
(0.3935"), or 16mm (0.630") stack heights. The data in this report is applicable only to the
16mm (0.630”) board-to-board spacing in 2:1 signal to ground ratio.
Purpose
This report presents the results of the 16mm ERM8/ERF8 connector response acquired in a 100
ohm differential measurement system transformed to an 85 ohm measurement system. The
purpose is to show how Samtec products will operate in an 85 ohm system.
The transformation process is described in Samtec Technical Note “Transformation of Samtec
Connector Test Data for 85 ohm Differential Impedance Applications”
Samtec Inc.
520 Park East Blvd.
New Albany IN 47151-1147 USA
©Samtec, Inc. 2005
WWW.SAMTEC.COM
1-800-SAMTEC-9 (US & Canada)
[email protected]
Page:1
Phone: 812-944-6733
Fax: 812-948-5047
Report Revision: 3/3/2009
All Rights Reserved
Electrical Performance Report
85 ohm Reference Impedance
Series: ERM8/ERF8 Edge Rate Strip Series
Description: 0.8mm (.0315”) Pitch, 16mm (0.630”) Stack Height
Differential Return Loss
Figure 1 shows the differential return loss for the 16mm ERM8/ERF8 connector with 100 ohm
reference impedance and with 85 ohm reference impedance. Notice that this connector has a
better match in a 100 ohm system up to approximately 4 GHz.
dB(TDA_import_85..S(1,1))
dB(S(1,1))
Differential Return Loss
0
-10
-20
-30
-40
-50
-60
0
2
4
6
8
10
12
14
16
18
freq, GHz
Figure 1. Differential Return Loss of Samtec 16mm ERM8/ERF8
Red – 100 ohm Reference Impedance, Blue – 85 ohm reference Impedance
Samtec Inc.
520 Park East Blvd.
New Albany IN 47151-1147 USA
©Samtec, Inc. 2005
WWW.SAMTEC.COM
1-800-SAMTEC-9 (US & Canada)
[email protected]
Page:2
Phone: 812-944-6733
Fax: 812-948-5047
Report Revision: 3/3/2009
All Rights Reserved
Electrical Performance Report
85 ohm Reference Impedance
Series: ERM8/ERF8 Edge Rate Strip Series
Description: 0.8mm (.0315”) Pitch, 16mm (0.630”) Stack Height
Differential Insertion Loss
Figure 2 shows the differential insertion loss of the 16mm ERM8/ERF8 connector with 100 ohm
reference impedance and with 85 ohm reference impedance. Notice that the difference in
transmission performance is fairly minor.
dB(TDA_import_85..S(2,1))
dB(S(2,1))
Differential Insertion Loss
0
-2
-4
-6
-8
0
2
4
6
8
10
12
14
16
18
freq, GHz
Figure 2. Differential Insertion Loss of Samtec 16mm ERM8/ERF8
Red – 100 ohm Reference Impedance, Blue – 85 ohm reference Impedance
Samtec Inc.
520 Park East Blvd.
New Albany IN 47151-1147 USA
©Samtec, Inc. 2005
WWW.SAMTEC.COM
1-800-SAMTEC-9 (US & Canada)
[email protected]
Page:3
Phone: 812-944-6733
Fax: 812-948-5047
Report Revision: 3/3/2009
All Rights Reserved
Electrical Performance Report
85 ohm Reference Impedance
Series: ERM8/ERF8 Edge Rate Strip Series
Description: 0.8mm (.0315”) Pitch, 16mm (0.630”) Stack Height
Differential Impedance Profile
Figure 3 shows the differential impedance profile of the 16mm ERM8/ERF8 connector with 100
ohm reference impedance and with 85 ohm reference impedance. The short length of 100 ohm
test traces are visible after the 85 ohm transformation (blue trace) at about 0.15 nSec. It is
important to note that the connector impedance response (between 0.3 nSec and 0.45 nSec) is not
affected by the choice of the reference impedance. This is the reason that a SPICE model of the
connector can be used in systems with a non-standard reference impedance such as 85 ohm
differential.
Differential Impedance Profile
TDA_import_85..TDR
TDR
120
110
100
90
80
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
time, nsec
Figure 3. Differential Impedance Profile of 16mm ERM8/ERF8
Red – 100 ohm Reference Impedance, Blue – 85 ohm reference Impedance
Samtec Inc.
520 Park East Blvd.
New Albany IN 47151-1147 USA
©Samtec, Inc. 2005
WWW.SAMTEC.COM
1-800-SAMTEC-9 (US & Canada)
[email protected]
Page:4
Phone: 812-944-6733
Fax: 812-948-5047
Report Revision: 3/3/2009
All Rights Reserved