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Full-Text Articles in Electronic Devices and Semiconductor Manufacturing

Design And Modeling Of A 40w Microwave Switch In Qfn 2x2 Package, Chin-Leong Lim Nov 2010

Design And Modeling Of A 40w Microwave Switch In Qfn 2x2 Package, Chin-Leong Lim

Chin-Leong Lim

This paper describes a Quad Flat Non-lead (QFN 2x2) packaged PIN diode switch that is capable of handling Continuous Wave (CW) power up to 40W and WCDMA signal up to 10W. The target application is the Transmit arm of a Transmit Receive switch for cellular base-stations. The part was developed in response to this market segment's aggressive cost-cutting pressure. Prior designs relied on more expensive ceramic packages.


Lna Based On A Low Cost (~Usd1.30) Commercial Gaas Phemt Mmic Offers Wideband (0.4~1.4 Ghz) And Room-Temperature Low Noise (~0.3 Db) Performances That Satisfy The Ska Low Cost And No-Cooling Requirement, Chin-Leong Lim Aug 2010

Lna Based On A Low Cost (~Usd1.30) Commercial Gaas Phemt Mmic Offers Wideband (0.4~1.4 Ghz) And Room-Temperature Low Noise (~0.3 Db) Performances That Satisfy The Ska Low Cost And No-Cooling Requirement, Chin-Leong Lim

Chin-Leong Lim

Introduction: New generations of radio telescopes such as the Square Kilometre Array consist of millions of receivers scattered over a continent. The array’s quantity and geographic considerations ruled out the traditional radio astronomy LNA implementation; i.e. costly InP devices cooled by high-maintenance closed-cycle helium (He) refrigerators. Several LNA designs have been proposed to address the cost and room-temperature operation constraints but none appear a clear winner. Peltier and package-scale cooling have also been proposed as a lower cost/maintenance alternative to He cooling but when multiplied by the quantity required can still carve a significant chunk of the budget. Additionally, cooling …


Wideband Limiter Fits Sot-323 Pack, Chin-Leong Lim Jun 2010

Wideband Limiter Fits Sot-323 Pack, Chin-Leong Lim

Chin-Leong Lim

Limiters protect wireless receiver front-ends from damage due to signal overload. The Schottky-PIN limiter is more protective than the self-biased PIN limiter because the former's limiting threshold is ~10 dB lower. Present implementation of the Schottky-PIN limiter use separate PIN and Schottky diodes. Additionally, some prior knowledge is necessary to select the correct PIN and Schottky diodes for limiter service. To miniaturize the limiter and to simplify the diode selection process, we combined a pair of limiter-optimized PIN and Schottky diodes into a compact and low-cost SOT-323 package. This paper describes the design, fabrication and experimental validation of the industry's …


Pin Switch Protects Lna From Overloads, Chin-Leong Lim Mar 2010

Pin Switch Protects Lna From Overloads, Chin-Leong Lim

Chin-Leong Lim

The objective of this paper is to describe how a Microwave Monolithic Integrated Circuit (MMIC) can be paired with an external PIN diode bypass switch in the implementation of a Low Noise Amplifier (LNA) with overload protection feature for mobile TV receiver applications. In the preliminary phase of the design, competing schemes for reducing LNA gain were reviewed and their respective cost-performance trade-offs were benchmarked against the customer’s set of requirements. Based on the selected design, a “proof of concept” prototype was then assembled and tested. The key components of this switch by-passable LNA were sourced from in-house product portfolio, …


Lna With A Bypass Mode Improves Overload Resistance For Mobile Tv, Chin-Leong Lim Mar 2010

Lna With A Bypass Mode Improves Overload Resistance For Mobile Tv, Chin-Leong Lim

Chin-Leong Lim

Objective: This paper describes how a Microwave Monolithic Integrated Circuit (MMIC) can be paired with an external PIN diode bypass switch in the implementation of a Low Noise Amplifier (LNA) with overload protection feature for mobile TV receiver applications.

Method: In the preliminary phase of the design, competing schemes for reducing LNA gain were reviewed and their respective cost-performance trade-offs were benchmarked against the customer’s set of requirements. Based on the selected design, a “proof of concept” prototype was then assembled and tested.

Material: The key components of this switch by-passable LNA were sourced from in-house product portfolio, consisting of …