RF switch core — PIN diode in SOD-323
The Infineon BAR6503WE6327HTSA1 is a single PIN diode designed for RF switching and attenuator applications. It handles up to 100 mA forward current and blocks 30 V peak reverse. On-resistance sits at 900 mOhm when biased at 10 mA at 100 MHz, with a junction capacitance of 0.8 pF at 3 V reverse bias and 1 MHz — numbers that define insertion loss and isolation in the signal path. The SOD-323 package (PG-SOD323-2) keeps the footprint small for dense RF front-end boards.
The 900 mOhm resistance at 10 mA forward bias sets the series loss when the diode is on — lower resistance means less signal attenuation through the switch. The 0.8 pF capacitance at 3 V reverse bias determines how well the diode isolates the RF port when it's off; lower capacitance improves isolation at higher frequencies. Together they define the on/off ratio the designer can expect in a shunt or series configuration. The 100 mA current rating is the DC bias limit, not the RF envelope — the diode is meant to be DC-biased through an inductor or bias tee, not driven directly by the RF carrier.
Infineon lists the BAR6503WE6327HTSA1 as Active. RoHS3 compliant.