ILX Lightwave LDC-3712: 50/100 mA Laser Diode Controller, LDC-3700 Series

The ILX Lightwave LDC-3712 is a precision laser diode controller delivering selectable 50 mA and 100 mA current output for low to medium power laser diode applications. It combines a high-stability, low-noise current source with a 32 W integrated temperature controller, offering both constant current and constant power operating modes. The instrument provides 0.05% set point accuracy, sub-microradian stability to 20 ppm, and comprehensive laser diode protection including slow-start turn-on, output shorting relays, and independent adjustable current limits. Temperature control spans −100°C to 199.9°C with ±0.004°C stability.

Technical Specifications Laser Current Source

Current Ranges: 50 mA and 100 mA selectable

Set Point Accuracy: 0.05%

Resolution: 1 µA (50 mA range), <2 µA (100 mA range)

Noise and Ripple: <1.5 µA both ranges

Stability: 20 ppm

Operating Modes: Constant Current (CC) and Constant Power (CP)

Modulation: Up to 1 MHz analog modulation (high bandwidth CC); up to 15 kHz low bandwidth CC mode

Laser Forward Voltage: 4-wire measurement

Compliance Voltage: Adjustable limit

Current Limit: Independent, adjustable during operation Temperature Controller

Integrated Power: 32 W

Temperature Range: −100°C to 199.9°C

Stability: ±0.004°C

Set Point Resolution: 0.01°C

Measurement Accuracy: 0.05°C (with calibrated sensor)

Sensor Types: Thermistor, IC, RTD (includes calibrated 10 kΩ thermistor TS-510)

Operating Modes: Constant Temperature (CT), Constant Sensor (CS), Constant TE Current (CTE)

TEC Forward Voltage: Supported for power consumption monitoring

Safety: Automatic laser current shutdown and fault indication on open temperature sensor or TE circuit General

Interface: GPIB/IEEE-488; USB available on select LDC-3700C models

Display: 5-digit green LED for laser and TEC parameters

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

Key Features

Dual-range current source with independent adjustable limits

Intermittent contact protection and output shorting relays

TEC forward voltage measurement for total module power monitoring

Multi-sensor support with automatic calibration

Typical Applications Low to medium power laser diode systems requiring precise current and temperature stabilization, including laboratory test setups and OEM integrated modules.

Compatibility & Integration GPIB/IEEE-488 remote control standard; USB interface available on LDC-3700C series variants. Operates on standard 100–240 VAC single-phase power.