| 摘要 |
A laser diode current drive control circuit including a drive circuit supplying a modulated laser diode current drive signal, a laser diode drive current source having a switch responsive to the drive circuit for controlling flow of drive current to the laser diode. The control circuit is further provided with one or more fault sensing circuits coupled to the diode current switch and responsive to a fault condition in the operation of the diode that would cause the diode power output to exceed a predetermined maximum safety limit to open the switch thereby terminating the flow of diode drive current. A feedback sensing circuit operating synchronously with the current drive signal is effective to open the switch when a normal feedback control signal is lost. A drive signal sensing circuit is effective to open the switch when integrated power output of the laser diode exceeds a safety related limit value. The fault sensing circuits are integral with the laser drive circuit and operate independently of the separate controller circuits.
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