PCX-150

The PCX-150 is an air-cooled, high power pulsed current source designed to drive diode lasers, bars and arrays. It delivers current pulses variable from 1A to 150A, pulse widths variable from <50ms to 5ms, with rise times <5ms, and pulse repetition frequencies variable from single shot to 5KHz at duty cycles up to 20%.

A microprocessor-controlled front-panel and RS-232/IEEE-488 interface of PCX-150 provide individual control of each electronic function,while the backlit display provides immediate visual confirmation of all operating parameters, including output current setpoint and amplitude, pulse width, repetition frequency, duty cycle, and error and fault messages. The front panel controls allow the user to set either pulse width and frequency independently, or to set frequency and duty cycle, which then sets the pulse width accordingly. The front panel display of PCX-150 monitors both the setpoints,and the actual current delivered to the diode. Analog current and voltage monitors and a synchronization output are also provided for monitoring of the current and voltage to the laser diode. In addition to stand-alone operation, the PCX-150 can be externally triggered.

Connection to the laser diode is made through an innovative front panel, low impedance ribbon cable, designed to preserve the fidelity of high-speed, large-amplitude current pulses. The output connector is interlocked, so that the PCX-150 is disabled when the connector is removed.

The PCX-150 features advanced circuitry to protect both the diode and driver. A relay closure shorts the output to ground when power to the driver is turned off. At turn on, and at any time the driver is not pulsing, the PCX-150's output is electronically shorted to ground, ensuring that no current flows through the diode except during the on period of the pulse. In addition, the actual current through the diode is monitored in real-time. If the actual current ever exceeds the user-adjustable current setpoint,the driver truncates the output current pulse, electronically shorts the output to ground, and displays an error message on the frontpanel display. In addition, the PCX-150 has a factory-set hardware-controlled current-limit and an independent, useradjustable current limit. This provides a fail-safe mechanism to prohibit the user from setting the current amplitude setpoint above the user-controlled current limit.

A user-selectable slow-start option allows the user to configure a slow-start current ramp, as shown in the waveform below.Safety features of the PCX-150 include a laser enable keyswitch,an output cable safety interlock, remote interlock, and delayed .