Why are there so many diode types to choose from? How do I know what diode-type I should select?
Answer
The wide selection of diode types is due to the wide-ranging application space of our customers. The actual diode-choice corresponds to the LO drive level required to turn the diode ON and OFF (a.k.a. the diode barrier potential). Schottky diode turn-on voltages depend on the diode construction and range anywhere from around 0.25 V to as high a 1.1 V. For standard double balanced mixers, the low-barrier diodes (“L-type”) warrant LO drive levels around +7 to +10 dBm. Super-high barrier diodes (“S-type”) require LO levels from +19 to +22 dBm. The best advice is to determine how much LO drive is available in your system and select the diode option as specified in the datasheet.