Patent ID: 9077195
Filing Date: 2015-07-07
Classification: H02J

Abstract:
1. An input-output circuit that connects a connector including: at least a power supply terminal; and a first data terminal and a second data terminal, which are data terminals of a differential pair, and an internal circuit to each other, the input-output circuit comprising: a power supply detection circuit that detects power feeding to the power supply terminal from the outside; and a charger detection circuit that specifies the kind of charger by detecting voltages of the first data terminal and the second data terminal, wherein the charger detection circuit detects open, pull-up, pull-down of at least one of the first data terminal and the second data terminal, or formation of a short circuit between both the terminals, wherein the charger detection circuit includes: a first comparator that compares a voltage of the first data terminal and a first reference voltage; a second comparator that compares a voltage of the second data terminal and a second reference voltage; and a determination circuit that determines the kind of charger in accordance with output results of the first comparator and the second comparator.