Patent ID: 7889609

Claim:
A writing current circuit ( 42 ) adapted for supplying a controlled electrical current to a laser diode ( 34 ) included in a drive ( 10 ) that is adapted for swiftly recording a Digital Video Disc (“DVD”) ( 16 ), the writing current circuit ( 42 ) operating responsive both: a. to write control digital data for controlling operation of the writing current circuit ( 42 ), the write control digital data including data which specifies an amount of electrical current which the writing current circuit ( 42 ) controllably supplies to the laser diode ( 34 ); and b. to serial digital data which controls application of the electrical current to the laser diode ( 34 ) thereby specifying digital data to be recorded on the DVD ( 16 ), both the write control digital data and the serial digital data being received from a control processor ( 14 ) included in the drive ( 10 ), the writing current circuit ( 42 ) comprising: a plurality of separate current sources ( 62 ) each of which receives a single output signal from a current control register ( 58 ) included in the Writing current circuit ( 42 ), the output signal respectively received by each current source ( 62 ) from the current control register ( 58 ): a. when in a first state activating the receiving current source ( 62 ) for supplying a particular quantity of electrical current to the laser diode ( 34 ); and b. when in a second state deactivating the receiving current source ( 62 ) for supplying the particular quantity of electrical current to the laser diode ( 34 ), each current source ( 62 ), in addition to receiving the single output signal from the current control register ( 58 ), responds to a logical inverse of the single output signal for controlling overshoot in voltage applied to the laser diode ( 34 ).