SPS20 Cagire Low-Noise AC/DC Power Supply


  • 3U – 100mm x 160mm
  • Occupied width: 10HP (50.8mm)
  • 230V or 115V AC input
  • Chassis isolated output
  • DC output: 4 options
    • +5V/2.2A
    • +12V/2.2A
    • +15V/2.2A
    • +24V/1A
  • Low EMI : toroidal transformer & linear control
  • High reliability:
    • Current limiter
    • Overvoltage crowbar protection
    • Inrush current limiter
    • Thermal shutdown.
  • Low voltage noise
    • Density  ≤ 100 nV/√Hz
    • Ripple ≤  1mV RMS
  •  Connection: 2 options
    • DIN41612 H15
    • PCB terminal blocks (Cage Clamp™)
  • 3D models available

Contact Sisyph

SPS20 Cagire modules w/ DIN41612-H15 (right) or Cage clamp terminal blocks (left). Front panel not shown.


  • Low-noise DC power supply
  • Laser frequency stabilization
  • Opto-electronic oscillator
  • OPLL – Phase-locked lasers
  • Ultra-low noise current controller
  • Laser diode controller
  • RF noise sensitive prototyping


The SPS20 Cagire is a low-noise power supply based on a linear AC/DC converter. It was first designed to provide a quiet environment to operate our ultra-low noise laser current source (SMC-Series). For this purpose, three SPS20 modules are assembled in a 3U desktop case (SR100 Estélas) to power up to 2 complete
laser diode controllers and their dedicated laser frequency control electronics (SMA– and SMB-Series).
Because they have little to no ability to reject supply variations, many RF subsystems should also benefit from the low-noise features of the SPS20-Series to prevent unwanted side bands and low signal-to-noise ratio.

The SPS20 Cagire’s output  is protected against short-circuit using an adjustable current limiter. An overvoltage crowbar is also added on the output to provide ultimate protection of the loads. The SPS20 Cagire can be remotely controlled (on/off) using its dedicated isolated input. For more information refer to the functional block diagram.

Additional Views

SPS20 Cagire module : front view (left) and bottom view (right). Front panel not shown.

Rear views for the Cage Clamp™ terminal blocks option (left) and DIN41612-H15 option (right). Front panel not shown.