The present invention discloses a power supply circuit and method for a
USB 5G
millimeter wave
wireless network card, comprising a
USB socket, an input filter circuit, a plug detection circuit, a step-down circuit, a super
capacitor, a
delay switch circuit, a
filter capacitor, a
filter capacitor and a
wireless communication module; the
USB socket and the input filter circuit, the plug detection circuit, the step-down circuit, the super
capacitor, the
delay switch circuit, the
filter capacitor, the filter
capacitor and the
wireless communication module are interconnected to form a circuit. The present invention utilizes the characteristics of super capacitors, such as an
energy density greater than that of ordinary capacitors and less than that of
lithium batteries, and combines an ordinary step-down circuit and a simple
delay switch circuit to form a stable power supply
system, avoiding the unfavorable factors such as safety, volume, and cost brought about by the use of other
energy storage elements such as
lithium batteries. While reducing the design difficulty and saving costs, the
wireless network card becomes more refined, compact, stable, convenient, safe, and has a longer service life.