AT-42085G

Overview

The AT-42085G is a medium power silicon NPN bipolar transistor designed for high-frequency applications up to 6 GHz. Fabricated using a 10 GHz fT self-aligned-transistor process, it features a low-cost plastic package with a .085-inch diameter and 4-micron emitter-to-emitter pitch. Key electrical specifications at VCE = 8 V and IC = 35 mA include a typical output power of 20.5 dBm at 1 dB compression (P1dB) and a gain of 14.0 dB at 2.0 GHz. The device offers a typical noise figure of 2.0 dB at 2.0 GHz when biased at IC = 10 mA, supporting its use in low-noise amplifier configurations.

Feature Summary

• High gain-bandwidth product of 8.0 GHz typical fT
• Low noise figure suitable for LNA applications
• Medium power capability with easy impedance matching
• Lead-free option available with G suffix

Applications

• Wireless systems as a Low Noise Amplifier (LNA)
• Gain stage implementation
• Buffer circuits
• Oscillator designs
• Mixer applications

Procurement Notes

Verify the presence of the 'G' suffix in the part number to confirm lead-free compliance. Ensure the ordering quantity matches the specified packaging count of 100 devices per unit for the AT-42085G variant. Confirm that the supplier provides the original Avago Technologies datasheet or equivalent official documentation to validate the component's authenticity and technical specifications before purchase.

Selection Notes

Select this component for designs requiring a balance of medium power output and low noise performance in the sub-6 GHz range. The device is optimized for 50Ω noise matching near 1 GHz. Consider the thermal resistance of 130°C/W and derating requirements above 85°C case temperature during PCB layout. The 48-TQFP package is not applicable; this part uses a specific plastic axial-style package requiring appropriate mounting techniques.

Part Context

The AT-42085 belongs to Avago Technologies' lineup of general-purpose NPN bipolar transistors utilizing self-aligned-transistor technology. It is distinct from signal diodes or logic components, serving specifically as an active RF element. The 'G' suffix denotes a lead-free manufacturing variant, while the base model AT-42085 represents the standard composition. This family focuses on high-frequency performance within a cost-effective plastic housing.

Replacement Considerations

Publicly confirmed substitute part numbers are not provided in the source material. Engineers should consult manufacturer cross-reference guides or perform detailed parameter matching for alternative components.