UM4002B

RF Diode Overview

The UM4002B is a high power PIN diode from the UM4000 series, manufactured by Microchip Technology (formerly Microsemi). It features a silicon construction with long carrier lifetimes and thick I-regions. The device has a reverse voltage rating of 200 V at 10 uA. Electrical parameters include a forward voltage of 1.0 V at 100 mA, series resistance of 0.5 Ohm at 100 MHz, and capacitance of 3 pF at 100 V reverse bias. Power dissipation is rated at 25 W at 25°C stud temperature with a thermal resistance of 6°C/W.

RF Diode Feature Summary

• High charge storage and long carrier lifetime enable control of high RF levels with relatively low bias current.
• Peak RF voltages can be handled well in excess of applied reverse bias voltage.
• Non-cavity design provides structural integrity for high power applications.
• Compatible with automatic insertion equipment for manufacturing efficiency.

RF Diode Applications

• Low distortion switches and attenuators in HF through S band frequencies.
• High power UHF phase shifters and megawatt peak-power duplexers.
• Antenna selectors and couplers where inductance and capacitance elements are switched in filter or cavity networks.

RF Diode Procurement Notes

Verify the specific package style suffix against the datasheet mechanical drawings to ensure correct mounting compatibility. Confirm RoHS compliance requirements, as standard UM4000 devices use Sn/Pb finish while UMX variants meet EU Directive 2002/95/EC. Consult official Microchip documentation for current production status and ordering specifications before procurement.

RF Diode Selection Notes

Select the UM4002B when a 200 V reverse voltage rating is required for RF switching applications. Compare power dissipation capabilities against the UM4900 series if higher thermal performance is needed due to shorter thermal paths. Ensure the operating frequency range aligns with the device's carrier lifetime and capacitance characteristics for optimal switch performance.

RF Diode Part Context

The UM4002B belongs to the UM4000 series of high power PIN diodes designed for robust RF signal control. This series is electrically equivalent to the UM4900 series but typically offers lower power ratings due to longer thermal paths. The component is widely used in military and aerospace communication systems requiring reliable high-power handling.

RF Diode Replacement Considerations

The UM4902 is an electrically equivalent alternative within the same product family. Verify that the UM4902's higher power dissipation rating fits the thermal constraints of the application. For RoHS compliant replacements, consider the UMX4002 variant which utilizes a matte tin finish.