Drive current supply circuit
AssigneeHamamatsu Photonics K.K.
InventorsTakashi Suzuki, Seiichiro Mizuno
Life of this patent
Estimating the term…
Abstract
A drive current supply circuit is provided in which the speed of rise of the drive current to a laser diode is increased. In a drive current supply circuit for supplying drive current I to load 50 connected with the line 1R of two parallel lines 1R and 2R of a first current mirror circuit 1, this drive current supply circuit is provided with a control circuit CONT that controls the current i flowing in the other line 1L in accordance with first control signal Σø1 and the first control signal Σø1 comprises a steady DC component øD and a drive signal component ø1 added to the DC component øD when desired.
Claims3
A drive current supply circuit for supplying drive current to a laser diode used for reading data from and writing data on an optical disk, comprising:
- a first current mirror circuit having two parallel lines, said laser diode being connected with one of the two parallel lines;
- and
- a control circuit connected with the other of the two parallel lines, said control circuit controls the current flowing in this line in accordance with a potential of this line,
- this potential comprising a steady DC component when reading data;
- and
- this potential comprising a drive signal component added to said DC component when writing data.
Dependencies are inferred from the claim text.