The ILX Lightwave LDX-3620B is a battery-powered, ultra-low noise laser diode current source engineered for applications demanding narrow linewidth or stable wavelength laser operation. Delivering precision current output with exceptional noise performance and long-term stability, it excels in sensitive laser diode control applications. Extensive protection circuits safeguard against electrical transients, overcurrent conditions, and intermittent contact failures.
## Technical Specifications
**Current Output & Accuracy**
• Dual range: 200 mA / 500 mA maximum
• Output current accuracy: ±0.05%
• Set point resolution: 10 µA / 100 µA
• Monitor current range: 20–2000 µA
**Noise Performance**
• RMS noise (battery mode): <100 nA
• Laser diode output noise/ripple (low bandwidth): <70 nA
• Laser diode output noise/ripple (high bandwidth): <600 nA
• Current noise density: 815 pA/√Hz
• Wideband current noise: 850 nA rms
**Stability**
• 1-hour stability: <10 ppm
• 24-hour stability: <50 ppm FS
• Temperature coefficient: <20 ppm/°C
**Operating Modes**
• Constant current (low bandwidth): DC operation, optimized for laser protection and lowest noise
• Constant current (high bandwidth): Supports up to 1 MHz modulation for wavelength tuning
• Constant optical power: Measures laser diode photocurrent for stable optical output
**Modulation**
• External modulation bandwidth (high): DC to 1 MHz
• External modulation bandwidth (low): DC to 10 kHz
• Input 1 transfer function: 2 mA/V (10 V range)
• Input 2 transfer function: 5 mA/V (10 V range)
• AC or DC coupled inputs (fine and coarse)
**Compliance Voltage**: <5 V
## Key Features
• Adjustable current and voltage limits
• Slow-start routine prevents photodiode damage
• Normally closed shorting relay and semiconductor switch
• Floating output configuration
• Power line surge and EFT transient protection
• Error indicators for open circuit and power limit conditions
• Internal lead-acid battery: up to 16 hours operation
• Battery charge time: 15 hours
• Built-in charger with front panel indicator
• Low battery cutoff circuit
## Typical Applications
Narrow linewidth spectroscopy, wavelength-stabilized laser systems, optical frequency metrology, and precision laser power control requiring sub-nanosecond current noise and long-term output stability.
## Compatibility & Integration
Two external modulation inputs (fine and coarse) support analog control. No computer interfaces or remote I/O. Floating output enables flexible system integration.
