The Comchip Technology 1031946-CZRF52C18-HF is a zener diode that has a zener voltage (Vz) of 18V and a maximum impedance (Zzt) of 20 Ohm. This diode has a voltage forward (Vf) of 900mV at 10mA and a reverse leakage current of 100nA at 8.5V. It is mounted using SMD (SMT) technology and is packaged in 1005/SOD-323F. This zener diode has a maximum power dissipation of 200mW and has a temperature range of -55°C to 125°C. It is ideal for use in various discrete semiconductor applications.