User manual

OVERVIEW
11
Series Lineup / Main Features Series Lineup Model V Meter A Meter USB Tracking Error
GPD-3303D 3 digit 3 digit Yes
≤ 0.5% + 50mV of Master
GPD-3303S 5 digit 4 digit Yes
≤ 0.5% + 10mV of Master
Main Features Performance
• Low noise: Cooling fan controlled by Heatsink
temperature
• Compact size, light weight
Operation
• Constant Voltage / Constant Current operation • Tracking Series / Tracking parallel operation • Output On/Off control • 3 outputs: 30V/3A x 2, 2.5V/3.3V/5V/3A x 1 • Digital panel control • 4 sets of panel setup save/recall • Coarse and fine Voltage/Current control • Software calibration • Buzzer output • Key lock function
Protection
• Overload protection • Reverse polarity protection
Interface
• USB for remote control
GPD-3303 Series User Manual
12 Principle of Operation Overview
The power supply consists of the following.
• AC input circuit • Transformer • Bias power supply including rectifier, filter,
pre-regulator and reference voltage source
• Main regulator circuit including the main
rectifier and filter, series regulator, current comparator, voltage comparator, reference voltage amplifier, remote device and relay control circuit
The block diagram below shows the circuit arrangement. The single phase input power is connected to the transformer through the input circuit. Details of each part are described in the next page.
Block diagram