Friedrich Taenzler

Analog Signature- Driven Postmanufacture Multidimensional Tuning of RF Systems

Tuning knobs are becoming common in analog and RF devices for postsilicon calibration for variation tolerance and compensation. This article presents a low-cost, hardware-iterative technique based on a steepest-descent-based gradient search algorithm and demonstrates its utility in performance tuning of a 2.4-GHz transmitter system.

Octal-Site EVM Tests for WLAN Transceivers on "Very" Low-Cost ATE Platforms

Present day needs of RF IC manufactures for EVM tests in production testing from engineering and customer perspectives strongly demands massive parallel testing. This paper presents an industry development and deployment approach of octal-site, OFDM based broadband EVM tests on low-cost ATE platforms. Results obtained from an octal-site EVM solution for a WLAN transceiver is presented to validate the approach. The effects of repeatability and isolation of these tests in multi-site configuration are discussed. Also, a study of test time and test cost is presented to justify deployment of these tests in production.

Optimized EVM Testing for IEEE 802.11a/n RF ICs

Characterization of RF ICs based on their error vector magnitude (EVM) is gaining a lot of attention in the industry. In order to deliver this specification at a reasonable cost, the input test signal and the analysis techniques have to be optimized such that EVM testing can provide a robust pass/fail decision while utilizing a reasonable amount of tester resources. In this paper, we propose techniques to optimize EVM testing, both from input signal generation and from output analysis perspectives. Our goal is to achieve both efficient and reliable test approaches for WLAN (Wireless Local Area Networks) circuits.

Probe tip invasiveness at indirect electro-optic sampling of MMIC

Electric field disturbances induced by an electrooptic (EO) probe tip have been experimentally investigated up to 40 GHz by means of direct EO sampling. The results are compared with conventional network analyzer measurements. A field distortion depending on the working distance between the EO probe tip and the tested circuit, which has to be taken into account when using this technique for MMIC (monolithic microwave integrated circuit) characterization above 30 GHz, is shown.<<ETX>>

Characterization of a MMIC by direct and indirect electro-optic sampling and by network analyzer measurements

Abstract The internal frequency characteristic of a monolithic integrated 1 – 2 GHz travelling-wave amplifier based on GaAs-substrate is measured by using the direct (internal) and indirect (external) electro-optic sampling techniques. For the first time, an experimental comparison of both techniques is made. Moreover, the results are compared with conventional network analyzer measurements and simulations.

Contactless characterization of microwave integrated circuits by device internal indirect electro-optic probing

Deals with a contactless working test system for the internal test of monolithic microwave integrated circuits (MMIC) based on both: III-V-semiconductor and Si-substrate material. This electro-optic test system determines the electrical field above the test-point within the MMIC. Measurements demonstrate the capability of this test system for device internal function control and failure analysis.<<ETX>>

Use of polymeric materials for external electro-optic probing

Abstract The present paper offers a computational look into a new and potentially exciting area of external electro-optic probing. The benefits that might be derived from substituting polymeric materials as a prober tip for measuring fast electrical waveforms are presented. The large reduction of the perturbation of microwave circuits when tested by external electro-optic probing is calculated for the organic system PMMA/Disperse Red. This is an example for an organic prober tip material with an extremly low permittivity and good nonlinear optical quality and compared to the perturbation due to standard inorganic prober tip materials like LiNbO 3 or KD ∗ P.

Physics Based Fault Models for Testing High-Voltage LDMOS

This paper presents a fault model based test technique for high-voltage laterally-diffused metal oxide semiconductor field effect transistor (HV-LDMOS) to test for structural defects such as gate-FOX breakdown, gate-stress due to thermal overload and drain leakage due to high voltage stress. We have developed highly accurate equivalent circuit models for HV-LDMOS which is represented as a hybrid model and has been validated for different device geometries including both large and small gate-channels. The hybrid model is incorporated to develop fault models for testing and diagnosis of HV-LDMOS. We have developed fault models for structural defects by inducing their physical effect in the HV-LDMOS hybrid model. HV-LDMOS testing is performed by connecting the device in common-emitter configuration and computing its gain by using a chopped test stimulus and capturing the device response using a digitizer. The test measurements are further processed using a lock-in amplifier (noise-reduction scheme) in MATLAB-Simulink software platform. The proposed test technique is low-cost and highly accurate.

Production Test of High Volume Commercial RFIC

This presentation covers the motivations and constraints involved in multi-site testing of RF devices. A comprehensive list of these issues is documented in the following text.

Experimental characterization of the perturbations of microwave devices by the electro-optic probe tip

Abstract Disturbances induced by the electro-optic probe tip of an indirect electro-optic test system are studied experimentally and compared to simulations. It is shown that the probe tip can have a significant influence on the behaviour of the device under test (DUT) when not optimally positioned.