Microchip Technology UM4001E

Overview

UM4001E from Microsemi is a high-power PIN diode designed for RF switching and attenuation in HF–S-band systems. It features 200 V reverse voltage rating, 0.5 Ω typical series resistance at 100 MHz/100 mA, >5 µs carrier lifetime, low 3 pF capacitance at 100 V reverse bias, and operates in stud-mounted isolated package Style "E". It is used in UHF phase shifters and megawatt peak-power duplexers.

For engineers reviewing the UM4001E datasheet, UM4001E pinout, UM4001E application, or UM4001E equivalent, key selection criteria include reverse voltage capability, thermal path performance under pulsed RF loads, RF distortion behavior at high signal levels, and compatibility with automatic insertion equipment in high-reliability microwave assemblies.

Technical Context

The UM4001E employs a thick intrinsic (I) region and long minority-carrier lifetime (>5 µs) to sustain high RF current while maintaining low distortion in switching and variable attenuator topologies. Its non-cavity construction and thermally matched configuration minimize parasitic inductance and improve thermal transfer from chip to stud.

Rated for 200 V reverse voltage and capable of handling RF peak voltages well beyond applied DC bias, it supports operation in high-isolation, high-linearity RF paths where low capacitance (≤3 pF) and high parallel resistance (>10 kΩ at 100 V) are critical for insertion loss and isolation performance.

Key Specifications

Pinout & Package

UM4001E is supplied in Style "E" isolated stud-mount package: an electrically isolated metal stud with axial leads, optimized for high-power RF grounding and thermal dissipation via chassis mounting. The package provides low-inductance RF current paths and eliminates cavity-related resonance effects.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-power RF PIN diode applications.

Compared with UM4001E, UMX4001E offers identical RF and thermal behavior with lead-free finish, while UM4901E delivers superior steady-state power handling at the cost of slightly different thermal interface requirements-both require no PCB layout change but differ in compliance and thermal derating profiles.

Availability

UM4001E is available at Aetrix Electronics and suitable for UHF phase shifters, megawatt peak-power duplexers, antenna selector networks, and RF cavity tuning applications requiring stable component supply and long-term obsolescence management.

Supply support for UM4001E includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microsemi (now part of Microchip Technology) designs high-reliability analog and RF semiconductors for aerospace, defense, and industrial markets.

The UM4000 series targets high-power microwave switching and attenuation, emphasizing ruggedized packaging, low distortion, and proven field reliability in mission-critical radar and EW systems.

FAQ

What is the maximum reverse voltage rating for UM4001E?

The UM4001E has a reverse voltage rating of 200 V at 10 µA leakage current. This rating is verified under DC and low-frequency conditions; its ability to withstand RF peak voltages exceeds this value due to long carrier lifetime and thick I-region design. Always observe derating curves for elevated temperature or pulsed operation per the official UM4000/UM4900 datasheet.

Does UM4001E support automatic insertion assembly?

Yes, UM4001E is compatible with automatic insertion equipment. Its Style "E" package features standardized lead geometry and mechanical robustness suitable for high-speed placement and wave soldering. The device meets industry standards for lead coplanarity and thermal shock resistance required in automated RF module manufacturing lines.

How does UM4001E achieve low distortion in RF switching applications?

UM4001E achieves low distortion through a combination of long carrier lifetime (>5 µs), low series resistance (0.5 Ω), and thick intrinsic region design. These features enable linear RF current control with minimal harmonic generation, especially in analog attenuators and high-isolation switches operating from HF through S-band. Distortion performance is validated in thousands of hours of field use in UHF phase shifters.

What is the thermal resistance (θ_JA) of UM4001E in Style "E" package?

The UM4001E in Style "E" package has a thermal resistance of 6 °C/W when mounted at 25 °C stud temperature (Condition C). This value assumes direct metal-to-metal contact with a heatsink and is derived from absolute maximum ratings tables in the UM4000/UM4900 datasheet. Actual thermal performance depends on mounting torque, thermal interface material, and heatsink design.

Is there a RoHS-compliant version of UM4001E?

Yes, the RoHS-compliant version is designated UMX4001E. It uses a matte tin finish instead of Sn/Pb and meets EU Directive 2002/95/EC. All electrical and thermal specifications-including 200 V reverse voltage, 0.5 Ω series resistance, and Style "E" mechanical form-are identical to UM4001E. No redesign or qualification retesting is needed when substituting UMX4001E.