The 1N4148 is a small signal, high-speed switching diode. Typically found in a DO-35 glass axial package it is very useful at high frequencies and are very popular in low-current applications. Currently the 1N4148 is sourced by manufacturers such as Diodes, Inc., EIC Semiconductor, Fairchild Semiconductor, Microsemi Corporation, NXP Semiconductors, ROHM Semiconductor and Vishay Semiconductor.