PIN diode in 0805 — 250 V peak, 800 mOhm series resistance
The GMP4235-GM1/TR is a single PIN diode from Microchip's GIGAMITE® series, built for RF switching and attenuator stages where low capacitance and low series resistance are both required. It handles a 250 V peak reverse voltage, which covers most 50 Ω and 75 Ω RF front-end applications up through several watts of incident power. Series resistance is 800 mOhm at 20 mA forward current and 100 MHz — low enough that insertion loss in a shunt switch configuration stays under 0.3 dB through the low-GHz band. The 0.6 pF capacitance at 10 V reverse bias and 1 MHz keeps the off-state isolation high; at 2 GHz the capacitive reactance is about 130 Ω, so a single shunt leg provides roughly 15 dB of isolation.
0805 footprint and temperature range
Housed in the standard 0805 (2012 Metric) SMD package, the GMP4235-GM1/TR matches the footprint of a common chip resistor or capacitor — no special pad geometry needed. Operating temperature spans -55°C to 125°C, covering military and industrial thermal profiles without derating. The plastic SMT construction is non-hermetic, so the part is suitable for controlled environments or conformally coated boards but not for direct exposure to condensing humidity without protection.