ILX Lightwave CSM-39400: 4-CH Laser Diode Current Source Module

The ILX Lightwave CSM-39400 is a 4-channel laser diode current source module designed for integration into the LDC-3900 Laser Diode Controller mainframe. Each channel delivers independent, precision-controlled current to laser diodes with output ranges from 0 to 4000 mA and setpoint accuracy of ±0.1% of full scale. The module operates in both constant current and constant power modes, accommodating diverse laser diode driving requirements while protecting sensitive components through integrated safeguard circuitry.

Technical Specifications Drive Current Output

Output current range: 0 to 4000 mA

Setpoint resolution: 100 µA

Setpoint accuracy: ±0.1% FS

Compliance voltage: 5 V

Temperature coefficient: < 100 ppm/°C

Short-term stability (1 hr): < 20 ppm

Long-term stability (24 hr): < 40 ppm

Output noise/ripple: < 20 µA Current Limit Settings

Range: 0 to 4000 mA

Resolution: 16 mA

Accuracy: ±40 mA Photodiode Feedback (Transimpedance)

Photodiode current range: 0 to 20 mA

Current resolution: 1 µA

Current accuracy: ±0.05% FS

Output stability: 0.02%

Reverse bias: 0 to 5 V, adjustable Analog Modulation Input

Bandwidth (low): 0 to 2 kHz

Bandwidth (high): 0 to 50 kHz

Input impedance: 10 kΩ Power & Physical

Total power output: 20 W (4 A @ 5 V)

Dimensions: 10 × 8 × 8 in

Weight: 5 lbs

Key Features

Four independent channels with isolated control

Integrated laser diode protection circuits

High-resolution current control with 100 µA setpoint steps

Dual-mode operation: constant current and constant power

Transimpedance photodiode feedback with 0.05% FS accuracy

Low noise performance suitable for sensitive optical applications

Standard analog modulation input for external signal control

Compatibility & Integration The CSM-39400 installs directly into any of the four module bays on the LDC-3900 mainframe rear panel. Full electrical isolation between modules enables independent operation without cross-talk. Modules are readily interchangeable with other LDC-3900 current source, TEC, or combination modules. Class I equipment (grounded type) rated for indoor use only. Supply voltage fluctuations must not exceed ±10% of nominal.