ILX Lightwave LDC-3744C – Laser Diode Controller, LDC-3700 Series

The ILX Lightwave LDC-3744C is a precision laser diode controller integrating stable current source and thermoelectric temperature management. It delivers 0–4 A output with ±0.05% setpoint accuracy and sub-20 ppm/FS short-term stability, supported by dual-range current selection and comprehensive diode protection. The TEC subsystem maintains ±0.004 °C temperature stability over one hour across a −100 °C to +199 °C range, accommodating thermistor, IC, and RTD sensors. A photodiode monitoring channel with ±0.05% setpoint accuracy enables closed-loop optical feedback. Purpose-built for laser characterization, alignment, and manufacturing test, the controller combines low-noise performance (< 10 µA ripple, low bandwidth) with high-bandwidth capability (DC to 250 kHz) and includes slow-start, intermittent contact protection, and output shorting relays. GPIB and USB connectivity with LabVIEW drivers support integration into automated test systems.

Technical Specifications Laser Current Source

Output range: 0–4 A (dual 2 A / 4 A range)

Setpoint accuracy: ±0.05% of full scale

Resolution: 40 µA / 80 µA (dual range)

Short-term stability (1 hour): < 20 ppm FS

Long-term stability (24 hour): < 40 ppm/°C or < 40 ppm FS

Temperature coefficient: < 100 ppm/°C or < 100 ppm FS/°C

Noise & ripple (low bandwidth): < 10 µA

Noise & ripple (high bandwidth): < 20 µA

Bandwidth (low): DC to 10 kHz or DC to 15 kHz (external modulation)

Bandwidth (high): DC to 250 kHz

Compliance voltage: 10 V maximum

Current limit range: 0 to full scale Temperature Controller (TEC)

Output: −4 A to +4 A, ±8 V maximum

Maximum power: 32 W

Control range: −100 °C to +199 °C

Setpoint resolution: 0.1 °C

Stability (1 hour): ±0.004 °C

Stability (24 hour): ±0.01 °C

Current limit: 0–4 A with ±0.1 A accuracy

Current noise/ripple: < 1 mA rms

Sensor compatibility: Thermistor, IC, RTD Photodiode Monitoring

Measurement range: 5–5000 µA or 0–10,000 µA

Setpoint accuracy: ±0.05%

Current accuracy: ±4 µA

Reverse bias control: 0 to −5 V, user settable Monitor Current

Range: 5–10,000 mA

Accuracy: ±4 µA

24-hour stability: 2×10⁻⁴

Key Features

Dual-range current output with selectable 2 A or 4 A maximum

Slow-start and intermittent contact protection

Output shorting relays for safe diode handling

Bipolar TEC driver with independent current limiting

5-digit front-panel display

External modulation input (BNC)

Compatibility & Integration

GPIB and USB interfaces

LabVIEW drivers included

Power: 100–120 VAC or 220–240 VAC (±10%), 50–60 Hz

Dimensions: 127 mm H × 353 mm W × 345 mm D

Weight: 11.3 kg