Signal transmission device and switching power supply

摘要

A signal transmission device of aspects of the invention can include a master circuit connected to the primary sides of first and second transformers and a slave circuit connected to the secondary sides of the first and second transformers. The master circuit sets one of first and second transmitting/receiving circuits for transmitting operation and the other for receiving operation according to a control signal, and detecting a leading edge and a falling edge of the control signal, transmits a pulse signal with the pulse interval changing after a predetermined period of time. The slave circuit detects the change of the pulse interval of the signal received through third and fourth transmitting/receiving circuits and according to the detection result, sets one of the third and fourth transmitting/receiving circuits for receiving operation and the other for transmitting operation.

主权项

1. A signal transmission device comprising:
first and second transformers provided in parallel; a master circuit connected to terminals in a primary side of the first transformer and terminals in a primary side of the second transformer; a slave circuit connected to terminals in a secondary side of the first transformer and terminals in a secondary side of the second transformer; the master circuit including;
a first transmitting/receiving circuit for transmitting/receiving a signal to/from a side of the slave circuit through the first transformer,a second transmitting/receiving circuit for transmitting/receiving a signal to/from the side of the slave circuit through the second transformer, anda master control circuit that detects a leading edge and a falling edge of a transmitting signal to be transmitted to the slave circuit, sets one of the transmitting/receiving circuits for transmitting operation and the other for receiving operation, and transmits a signal with varying pulse intervals after passing a predetermined period of time since the detection of the leading edge or the falling edge; the slave circuit including;
a third transmitting/receiving circuit for transmitting/receiving a signal to/from a side of the master circuit through the first transformer,a fourth transmitting/receiving circuit for transmitting/receiving a signal to/from the side of the master circuit through the second transformer, anda slave control circuit that detects variation of the pulse intervals of a signal transmitting/receiving through the third and fourth transmitting/receiving circuit, sets one of the third and fourth transmitting/receiving circuits for receiving operation and the other for transmitting operation, and generates and transmits a pulse signal corresponding to transmitting signal to be transmitted to the master circuit.