LDP-3811 Newport Precision Pulsed Current Source

Model LDP-3811 is a microprocessor-controlled current source designed specifically to drive low power laser diodes. The unit operates in either stable continuous wave or precision pulsed mode and offers a dual range 200/500 mA output. An intuitive front panel makes it easy to adjust pulse amplitude, pulse width and repetition interval. Standard GPIB interface and flexible triggering offer complete system integration with other equipment in the lab, improving the ease and speed of data gathering and remote measurement.

Unlike many other pulsed current sources, the LDP-3811 has been designed to improve communication throughout the lab. The standard GPIB/IEEE-488.2 interface allows remote programming and readout from most computers. All instrument functions accessible from the front panel are also accessible through the interface bus.

The standard Trigger In/Trigger Out function is located on the rear panel. This feature provides the ability to trigger measurements from remote instruments, simplify data collection and certify accurate start and end points for pulse analysis.

The LDP-3811 offers a large range of adjustments designed to meet a wide variety of test parameters. Pulse amplitude and pulse widths can be set from 100 ns–1 ms, pulse repetition interval (PRI) from 1 µs to > 1 ms. A constant PRI mode permits adjustment of desired pulse width while maintaining PRI setting. In addition, the constant duty cycle mode allows maintenance of a preset duty cycle, regardless of how PRI or pulse width is adjusted. The intuitive front panel allows pulse characteristics to be set or changed easily. Operating modes are illuminated and informative fault indicators warn of potential damage to the laser diode.

The LDP-3811 minimizes pulse distortion by delivering an exceptionally clean pulse guaranteed to less than 5% overshoot. The unit’s low noise, transient-suppressed output is designed to drive 50 W.

The LDP-3811 also offers complete laser diode protection. Features like current limiting, overshoot minimization and transient protection have all been designed into the circuitry of the unit.