Accessory apparatus
AssigneeFujitsu Limited
InventorsYutaka Hosono, Teruaki Yagoshi, Kazuo Shimada
Life of this patent
Estimating the term…
Abstract
There is provided a device in an accessory apparatus, which is connected with a main apparatus, for protecting a motor driver IC and a logic circuit in the accessory apparatus from the application of a voltage higher than the rated voltage for these circuits, when the connection between the main apparatus and the accessory apparatus (optional apparatus) which receives power from the main apparatus enters an abnormal state. Therefore, even when the power of the main apparatus is ON, the accessory apparatus can be attached to, or removed from, the main apparatus without damaging the circuits. The device comprises an inexpensive element, such as a rectifying diode or a Zener diode.
Claims8
An accessory apparatus which is connected to a main apparatus and receives power from a power source of the main apparatus, comprising:
- a connector including a first terminal to be connected to a first power potential of the main apparatus, a second terminal to be connected to a second power potential of the main apparatus, and a third terminal to be connected to a ground potential of the main apparatus;
- a first circuit to be connected to said first, second and third terminals;
- and
- a first device for preventing said first circuit from being applied a voltage higher than a rated voltage of said first circuit in a direction from said third terminal to said first terminal in case that said second terminal is connected to the second power potential of the main apparatus with said first terminal being connected to the first power potential of the main apparatus, without said third terminal being connected to the ground potential of the main apparatus.
Dependencies are inferred from the claim text.