Wide input voltage range power supply circuit

摘要

A wide input voltage power supply circuit for a load includes a first stage and a second stage. The first stage includes a linear regulator circuit configured to maintain an output voltage at a predetermined output voltage level. The linear regulator includes an input for shutting the linear regulator off when an input voltage exceeds a predetermined shut off threshold. The second stage includes a high voltage detection circuit coupled to the input of the linear regulator. The high voltage detection circuit is configured to detect the level of the input voltage and to shut the linear regulator off when the input voltage exceeds the predetermined shut off threshold. An under voltage lockout circuit may be included, the under voltage lockout circuit configured to set a minimum turn-on voltage for the load.

主权项

1. A wide input voltage power supply circuit for a load, the circuit comprising:
a first stage comprising a linear regulator circuit configured to maintain an output voltage at a predetermined output voltage level, the linear regulator circuit including an input for shutting the linear regulator off when an input voltage exceeds a predetermined shut off threshold; a second stage comprising a high voltage detection circuit coupled to the input of the linear regulator circuit, the high voltage detection circuit configured to detect the level of the input voltage and to shut the linear regulator circuit off when the input voltage exceeds the predetermined shut off threshold; a capacitor snubber circuit coupled to an input of the high voltage detection circuit, the capacitor snubber circuit to divert current from a line inductance when the high voltage detection circuit turns the linear regulator circuit off, and an under voltage lockout circuit coupled to the power supply circuit, the under voltage lockout circuit configured to set a minimum turn-on voltage for the load and prevent operation of the load until the minimum turn-on voltage is reached.