Tuner Diodes Take Up To 50% Less Board Space

Said to occupy up to 50% less board space and to offer better performance than existing SOT23-packaged devices, SOD323 varactor diodes are based either on hyperabrupt or high ratio hyperabrupt junction profiles. In tuned circuits, the devices have a minimum quality factor Q from 80 to 350 with test conditions of 50 MHz and a low VR of 3V or 4V. With a reverse breakdown of 25V, the Hyperabrupt ZMV830 series of SOD323 tuners offers a nominal capacitance range between 8.2 and 68 pF for a VR of 2V and frequency of 1 MHz. At the same frequency, a minimum C2/C20 capacitance ratio of 5, twice that of abrupt junction types, demonstrates how the device capacitance changes with applied voltage. The diodes are available with a 5% tolerance. The ZMV900 series of miniature diodes demonstrates an even faster change in capacitance for a change in bias voltage, a quality particularly useful in battery-powered applications. With the mid-range ZVM933 device, a VR of 1V demonstrates a capacitance of 42 pF, falling to 12 pF as bias rises to 4V. Breakdown for the device is 12V.