Download - Multiport Calibration
Multiport Calibration
ATE Architecture, Design and Support
What We Do
Solve challenging high-speed and microwave measurement problems, providing customers with accurate, reliable, and repeatable data
FixturingCalibration & Error CorrectionReference Plane Positioning
Areas of Expertise
Test System HW & SW Develop-ment
Measurement Science
Fixturing
Calibration & Error Correction Data
Analysis
ATE System Development
•RF•High-Speed•Multi-port
•SMT•Non-coaxial•Device-specific
•Conventional•Novel •Signal Integrity
•Power Integrity
Simple
Company Philosophy
Fast
Simultaneously make measurement systems:
Accurate
Description of Problem
• Multi-port Device Under Test• Switch Matrix & Test Cables have non-
negligible loss, group delay, dispersion• Must calibrate at DUT port• Calibration must be done at least once
per day• Manual calibration is time-consuming
and error-prone• Time required to calibrate reduces
system throughput
Why It Matters
• Poor (or no) calibration results in poor measurement accuracy• Poor accuracy causes
- Bad parts to pass through, or- Good parts to be scrapped
• Both represent real costs through- Higher-level system failures & customer relations issues, or- Increased material costs due to scrapage
• Time required for calibration takes away from system throughput and must be minimized to reduce cost per tested part
Conventional ApproachesDescription Advantages Disadvantages
SOLT cal at VNA only
Simple, fast Poor accuracy
SOLT cal at DUT ports
Potential for very good accuracy
Very time consuming for large devices
Manual process is error-prone
SOLT cal at VNA, characterize and de-embed to DUT
Potential for good accuracy
Tedious to characterize each path
Cal not updated for changes due to environment or mechanical flexure
ATE Solution
1 Calibrate at VNA test ports
2 Automatically characterize interconnect path in situ
Calibration can be done with DUT connected
3 Measure DUT
Measurement done with cal modules connected
4 Automatically de-embed interconnect and display data at DUT reference plane
Instrument Calibration
Module
FCM
FCM
FCM
FCM
FCM
FCM
FCM
FCM
Reference PlanesFCM = Fixture Characterization Module
VNA & ICM
Fixture Characterization Module
Calibration Procedure
4-Ports2000 pointsIFBW = 3000HzCalibration time = 48 sec
Measurement Procedure
4-Ports2000 pointsIFBW = 3000HzMeasurement time = 9 sec
2-Port Probe System Configuration
2-port Calibration Process: Bring Port 1 probe down on Short Measure Short on Port 1 Bring Port 1 probe down on Open Measure Open on Port 1 Bring Port 1 probe down on Load Measure Load on Port 1 Bring Port 2 probe down on Short Measure Short on Port 2 Bring Port 2 probe down on Open Measure Open on Port 2 Bring Port 2 probe down on Load Measure Load on Port 2 Bring Port 1 and Port 2 probes down on Thru Measure Thru between Ports 1 & 2
2-port Calibration Process: Press Calibrate Button
Option 1Traditional ApproachATE Approach
2-Port Probe System ConfigurationOption 2
Calibration Process: Bring Port 1 and Port 2 probes down on Thru Measure Thru between Ports 1 & 2
Compared to Option 1: Hardware configuration simplified Does not allow calibration on-the-fly
ATE Approach
4-Port Probe System Configuration
Switch Matrix
4-port Calibration Process: Approximately 30 steps4-port Calibration Process: Press Calibrate Button
Traditional ApproachATE Approach
Software: Programmatic Module Control
• SCPI-based command set• TCP/IP over Ethernet• VISA compatible• Web Browser Interface to configure Module Controller• Full VISA-based LabVIEW and CVI Wrappers provided
Example Command (Set FCM at module port 5 to thru state):CONTROL:FCM5:STATE THRU
Software: Automated Cal with TruCal
• Application Programming Interface (API) for all ATE Calibration Algorithms
• Standard Win32 DLL• Callable from any language/IDE that supports DLL
access (e.g. C, C++, LabVIEW, CVI, VB, etc.)• Uses rudimentary C data types for maximum
compatibility• Full LabVIEW API Wrapper provided
Example Function (Initialize 2-port algorithm):TC2P_Initialize(double* dFreqs, int nFreqs, int nStates);
Characteristics: Automated
• In situ calibration allows system to be calibrated without removing DUT and connecting standards
• No manual, error-prone operations• Fast calibration improves system availability• Non-intrusive calibration allows it to be done more
frequently
Characteristics: Accurate
• Calibration transfer standards have TRL-level accuracy• In situ calibration removes inaccuracies resulting from
test cable performance with flexure of conventional cal methodologies
• Fast calibration facilitates more frequent calibration as needed
Characteristics: Cost-Effective
• Improved accuracy avoids costs associated with shipping bad material resulting in high-level system failure and customer dissatisfaction
• Improved accuracy avoids scrapping good material just when it has the maximum value-added, reducing manufacturing cost
• Increased system up-time reduces cost per tested part by being able to test more devices in a shift
Contact information
For more information please contact us at:
ATE Systems, Inc. Phone: +1-978-362-185085 Rangeway Road email: [email protected] Billerica, MA 01862 http://www.atesystems.com