PL Series Features:

• 180 Watts; 2 x (0 to 30V at 0.1mA to 3A), or 1 x (0 to 30V at 0.2mA to 6A), plus 0 to 6V at 0 to 8A
• High accuracy four-digit meters
• S-Lock digitally locks voltage and current settings
• True analog controls make adjustment quick and simple
• V-Span enables the full 300° rotation of the voltage control
• Safety binding post terminals can accept fixed-shroud 4mm plugs
• DC output switch enables voltage and current to be set up before connecting the load
• Voltage sensing can be changed between local and remote
• Bus programmable via USB, RS232, LAN [PL303QMD-P), GPIB incl. w/ PL303QMD-P(G)]
• LAN interface is LXI compliant [PL303QMD-P, PL303QMD-P(G)]

Analog control for a digital world
TTi PL303QMD is a dual output power supply with the same high power density as the single output models: 180 watts from a half-rack 3U sized casing (214mm x 131mm x 288mm). The PL303QMD is more than just two PL303 single power supplies in one box. It has four modes of operation: Independent, Isolated Tracking, Isolated Ratio Tracking, and True Parallel.

• Independent Mode: The two outputs are completely independent and electrically isolated from each other.
• Isolated Tracking Mode: The two outputs remain electrically isolated, but the voltage control of the Master output sets an identical voltage on the Slave output.
• Isolated Ratio Tracking Mode: As normal tracking, but the Slave voltage can be set to any percentage of the Master voltage and retains that ratio as the Master voltage is varied.
• True Parallel Mode: All of the power is channeled to the Master output which can then supply up to 6 amps.

Simultaneous Output Control
The Both On/Both Off buttons are in addition to the individual switches for each output, and allow both outputs to be turned on or off synchronously by a single button press. Synchronous switching of the outputs is of increasing importance for circuitry which can be damaged if one voltage rail is present without the other.

Analog controls with digital stability
The main disadvantage of analog controls is stability and security. The settings of analog potentiometers an drift over time. More importantly, the settings can be changed accidentally with potentially serious consequences. The PL303QMD and PL303QMD-P introduce S-Lock. One press of the Lock button transfers control of voltage and current from the analog controls to internal digital circuitry. This offers not just complete security, but exceptional stability as well with each setting controlled by an instrumentation quality DAC.

Analog Remote Control
Single output PL-P units include analog voltage control of voltage and current (non-isolated). Analog control outputs are also incorporated to enable easy parallel connection of multiple units in a master-slave configuration. Terminals for remote on/off control are also provided. Note PL303QMD-P does not have analog remote control.

Linear regulation for ultra-low noise
Linear regulation still offers the lowest output noise and the best transient response (recovery time from a sudden current step). Most linear regulated power supplies offer low output noise with figures below 2mV RMS being typical. The PL303QMD and PL303QMD-P goes a stage further and an RMS noise figure of 0.4mV with tightly specified pk-pk noise and common-mode current figures.

Ultra-compact design with higher power efficiency and near-silent cooling
The PL303QMD and PL303QMD-P achieve an exceptional power density for a linear regulated power supply by offering 75 watts from a 1/4 rack 3U sized casing. This gives it an unusually small bench footprint taking up less space on a crowded bench. For rack-mount application, up to four PL-Series supplies can be mounted into a single slot. Despite their small size and linear regulation, they generate relatively little heat through the use of an advanced phase controlled preregulator. This gives the PL303QMD and PL303QMD-P significantly higher energy efficiency than conventional linear regulated designs, particularly when supplying lower voltages. The internal heat-sinks use fan-assisted convection cooling in order to remove the heat with minimal fan noise.

Choose a voltage range that suits your task
When working with any particular piece of equipment, you may require a voltage source variable over only a narrow range. Set the voltage too high and damage might occur, set it too low and the circuit may reset. That's where the V-Span function of the New PL series comes in. It allows the you to redefine the end-stop values of the voltage control to define a specific voltage range. For example: you're working on a circuit that will eventually operate from four NiMh cells, use V-Span to set a Vmax of 5.8 volts (to prevent over-voltage damage) and a Vmin of 3.6 volts (to ensure that the circuit doesn't reset). You now have a power supply which provides high resolution analog control over the exact voltage range needed. Vmin and Vmax can be set anywhere between zero and maximum output voltage subject only to Vmax > (Vmin + 0.1V). The fine control gives additional adjustment of ±1%. Once set, the voltage span function can be turned on or off at the press of a button.

Advanced Bus Programmable DC Power Supplies
Interfacing to every application, the PL303QMD-P and PL303QMD-P(G) are bus programmable and includes all of the manual control features of the PL series, but adds comprehensive remote control facilities. The ultra-compact rack-modular sizing makes it ideally suited to rack mounted system applications, while its user-friendly manual controls are retained for bench top applications. Digital Interfaces to meet the varying needs of today's engineers, a comprehensive array of interfaces is provided. RS-232, USB and LAN (Ethernet) with LXI support are provided as standard. Each of the digital bus interfaces provides full control of voltage, current, and output on/off, plus read-back of voltage, current and status. A model (PL303QMD-P(G)) with GPIB interface is also available.

Additional interface options with PL303QMD-P DC Power Supply:

• Rear Power Terminals
  Power and sense terminals are duplicated on the rear panel for rack mount applications or other situations where rear connection is more appropriate.
• Analog voltage control of voltage and current (non-isolated).
• RS-232, USB and LAN (Ethernet) with LXI support are included with PL303QMD-P
  RS-232/RS-423 interface is provided for use with legacy systems. USB provides a simple and convenient means of connection to a PC
• LAN-Ethernet with LXI
  The LAN interface uses a standard 10/100 base-T Ethernet hardware connection with ICMP and TCP/IP Protocol for connection to a Local Area Network or direct connection to a single PC. The LAN interface is compliant with LXI-C.
  Each of the digital bus interfaces provides full control of voltage, current, and output on/off, plus read-back of voltage, current and status. The interfaces are at ground potential and are opto-isolated from the output terminals.
• IVI Driver
  An IVI driver for Windows is included. This provides support for common high-level applications such as LabView, LabWindows, and HP/Agilent VEE.
• GPIB (option G)
  PL303QMD-P(G) is fitted with a GPIB (IEEE-488) interface in addition to USB, RS232 and LAN.

Comprehensive Array of Interfaces RS-232, USB and LAN (Ethernet) with LXI support are provided as standard, with GPIB an option. Each provides full control of voltage, current, and output on/off, plus read-back of voltage, current and status. The interfaces are opto-isolated from the output.