What this X-band mixer diode is
The Infineon BAT15-098LRH is a low-barrier Schottky diode array — two pairs with a common cathode — designed for X-band mixer and detector stages. Its key spec is the 0.5pF capacitance at zero bias (1 MHz), which keeps the RF insertion loss low up into the X-band. The 4V peak reverse voltage limits the local-oscillator drive level, so this is a small-signal mixer diode, not a power rectifier.
The 0.5pF junction capacitance at 0V is the figure that determines how high in frequency this diode can mix before the capacitive reactance shunts the RF signal. For an X-band down-converter, that 0.5pF keeps the conversion loss in check. The 4V reverse rating means the LO and RF signal peaks must stay under 4V — typical for a low-barrier Schottky in a receiver front-end. Exceed that and you forward-bias the diode, distorting the IF output.
Package and handling for field swap
The BAT15-098LRH comes in a PG-TSLP-4-7 package — a 4-lead XFDFN. The common cathode is pin 1, marked by a dot on the package top.
The BAT15-098LRH is an active Infineon part, ROHS3 compliant. It is available through independent distribution.