Introbotics Corporation Repeatability Study.

REPEATABILITY STUDY

Today's controlled impedance testing is more of an art form than a science. Controlled impedance testing is currently performed manually with a hand-held probe, as shown below.

Clearly, the repeatability and accuracy of this manual process is highly variable.

Introbotics has has solved the repeatability and accuracy problems inherent with manual controlled impedance testing. Introbotics CI1000™, Controlled Impedance Tester, uses a robotic system, an automated calibration source and a TDR standard to achieve exceptional repeatability and accuracy.

The following study was performed for Rambus on January 28, 2000 and reported on February 5, 2000. The study was consistent with Intel's "PCB Test Methodology, Rev 1.5".

Study Summary

The Rambus benchmark data was gathered on the CI1000™. This system was specifically designed to take controlled impedance measurements on printed wiring boards (PWB), coupons, and panels.

Study Equipment Used

		Tektronix 11801C Digital Sampling Scope (SN# B020508, upgrade), last calibrated 8/4/1999
		SD-24 TDR Sampling Head (SN# B021544)
		SD-24 Calibration Record: August 4, 1999, 15.2 pico-second rise time
		Cntinental Microwave High Frequency Probe Assembly
		Probe Calibration Record: February 2, 2000, 38 pico-second rise time
The CI1000™		28 ohm Airline Standard (Maury Microwave)
		CI1000, Controlled Impedance Tester (SN# 0001)

Study Procedure

Two coupons were provided by Rambus for testing. Each coupon was tested with 20 tests.

Study Results

Test Run	Coupon #1	Coupon #2
1	26.16	26.26
2	26.14	26.21
3	26.19	26.24
4	26.14	26.26
5	26.18	26.25
6	26.13	26.25
7	26.16	26.25
8	26.17	26.27
9	26.17	26.27
10	26.15	26.23
11	26.13	26.25
12	26.17	26.24
13	26.18	26.25
14	26.14	26.23
15	26.13	26.30
16	26.16	26.24
17	26.15	26.24
18	26.16	26.23
19	26.10	26.20
20	26.13	26.20
Mean	26.152	26.244
Min	26.10	26.20
Max	26.19	26.30
Spread	0.09	0.10
Std. Dev.	0.022	0.024

Calibration offsets:

For Coupon #1 = 48.9559
For Coupon #2=48.9559

Note: These values are the recorded apparent impedance value of the in-line semi-rigid cable as determined by a measurement against the 28 ohm airline. These offsets were applied to the values before entering coupon impedance measurements in the table.

Operator: Brian D. Butler

INTROBOTICS CORPORATION
4208 Balloon Park Road NE Albuquerque, NM 87109
Tel: (505) 345-7785 Fax: (505) 345-7790 Email: info@introbotics.com