ILX Lightwave LDX-3565: Precision Current Source, 2/6 A, LDX-3500B Series

The ILX Lightwave LDX-3565 is a precision current source designed for laser diode driver applications requiring stable, accurate output across dual current ranges. Operating in constant current (low and high bandwidth) or constant optical power modes, the LDX-3565 delivers set point accuracy of ±0.1% full scale with output noise as low as 50 µA in low bandwidth mode. The instrument supports analog modulation input up to 500 kHz for power and wavelength tuning, photodiode current measurement for closed-loop optical power control, and comprehensive laser diode protection including adjustable current limits, shorting relays, slow turn-on circuits, and transient protection.

USB 2.0 connectivity with LabVIEW driver support enables remote instrument control and integration into automated test systems. The compact 88 mm × 185 mm × 304 mm chassis houses an intuitive front panel interface with five-digit LED display and error indicators, making it suitable for research, manufacturing test, and production environments.

Technical Specifications

• Output Current Ranges: 2 A / 6 A dual ranges


• Maximum Output Current: 6 A


• Set Point Accuracy: ±0.1% full scale (±2 mA at 2 A range; ±6 mA at 6 A range)


• Set Point Resolution: 500 µA, 1.5 mA, or 1.0 mA selectable


• Output Accuracy: ±0.1% full scale


• Compliance Voltage: 5 V maximum


• Output Noise: 50 µA rms (low bandwidth); <2 µA rms (high bandwidth)


• Temperature Coefficient: <50 ppm/°C to <100 ppm/°C


• Photodiode Measurement Range: 0–25 mA (selectable ranges: 0–5 mA, 0–10 mA, 0–25 mA)


• Analog Modulation Input: 0–10 V, up to 500 kHz, 200 mA/V transfer function

Key Features

• Constant current and constant optical power control modes


• Photodiode current measurement for closed-loop feedback


• Adjustable current limits and shorting relay protection


• Slow turn-on and transient protection circuits


• Analog output for remote monitoring


• USB 2.0 interface with LabVIEW driver support


• Intermittent contact and interlock shutdown protection

Typical Applications

• Laser diode characterization and testing


• Automated manufacturing test systems


• Research and development


• Optical power regulation and control

Compatibility & Integration USB 2.0 connectivity supports fast, repeatable control with remote operation capability. Analog modulation input (BNC) enables wavelength and power tuning. Photodiode feedback path supports constant optical power operation.