Interface circuit which meets universal serial bus standard and performs host and device functions

摘要

When a device such as a printer is connected to a connector 49 via a USB cable using an electronic device 40 as a host, a selecting circuit 43b is switched to a host function circuit 43a by operating a switch 42. When a host such as a personal computer is connected to the connector 49 via the USB cable using the electronic device 40 as device, the selecting circuit 43b is switched to a device function circuit 44a by operating the switch 42. A USB interface is controlled according to output of a microcomputer 41. Therefore, an interface circuit which meets USB standards, facilitates switching between a host function and a device function, has a simple circuit configuration and allows small-sizing can be provided.