DMJ3940-257

• Low 1/f noise
• Low intermodulation distortion
• Epoxy and hermetically sealed packages
• SPC controlled wafer fabrication

DME, DMF, DMJ Series: Silicon Beam-Lead Schottky Mixer Diodes-Singles, Pairs and Quads Bondable and Packaged Chips

Skyworks beam-lead silicon Schottky barrier mixer diodes are designed for applications through 40 GHz. DMJ3940-257 design reduces the problem of bonding to the very small area characteristic of the low capacitance junctions. DMJ3940-257 Schottky barrier mixer diodes are made by the deposition of a suitable barrier metal on an epitaxial silicon substrate to form the junction. The process and choice of materials result in low series resistance with a narrow spread of capacitance values for close impedance control.

A variety of forward voltages are available, ranging from low values for low, or starved, local oscillator drive levels to high values for high drive, low distortion mixer applications. Beam-lead diodes are available in a wide range of packages. Capacitance ranges and series resistances are comparable with the packaged devices that are available through K-band. Unpackaged diodes are well suited for use in microwave integrated circuits. DMJ3940-257 are designed to be inserted as hybrid elements in strip, transmission line applications.

DMJ3940-257 Schottky barrier diodes are categorized by universal mixer applications in four frequency ranges: S, X, Ku and Ka bands. DMJ3940-257 may also be used as modulators and high-speed switches.

DMJ3940-257 diodes are suited for balanced mixers, due to their low parasitics and uniformity. A typical VF vs. IF curve is shown in Figure 1. Typical noise figures vs. LO drive is shown in Figure 2 for single N-type, low drive diode types.