The MMBF4091 with JFET N-Channel Switch is a part manufactured by ON Semiconductor. It is a small signal, low voltage, 4-terminal, N-Channel JFET-based switching device, designed to be used in analog and digital circuits. This part is ideal for use with low voltage and sensitive components, as it operates at a forward transconductance of 1.3mS and saturation voltage of 0.3V. It also offers excellent thermal and electrical stability, eliminating the need for temperature compensation. The device is available in both through-hole and surface mount packages, and is rated to handle up to 400mA of current. Additionally, the MMBF4091 has an ESD rating of 8kV with high Junction-to-Case thermal resistance, making it safe and reliable for use in a variety of applications.