02001346 Rev 1
HPP-1000/6000 User Manual
Page 4 of 19
2.
Description of HPP System
Lumina Power’s HPP power supplies are designed for pulsing diode lasers in Quasi-CW
applications. Before operating this unit, it is important to understand the operation. A
block diagram of the power supply is shown below.
High Power
Linear Regulator
DC
Input Voltage
Control System
Hall Effect
Sensor
Laser
Diode
Iout Control
Iout Monitor
Figure 1, HPP Block Diagram
Referring to Figure 1, it’s easiest to think of the basic elements of the system as a high
power linear regulator. The four main components are:
•
A
storage capacitor
which holds the energy for a high power pulse.
•
A
high power linear regulator
which is controlled by an error signal.
•
A
high current sensing circuit.
•
Control system.
The
DC input voltage
source must be voltage programmable and have current limit but
not fold-back. It must be able to deliver constant current into a big capacitor which is a
short at start up and the voltage will be discharged to a low level at the end of every
pulse. Set the output voltage at 2 to 5V higher that the load compliance voltage for
optimal efficiency.
Even though the HPP output current has better than 15us rise/fall time, the compliance
voltage is only a few volts higher than the load voltage and the LDD-xx-yy-HP will
perform this requirement automatically.
The
high power linear
regulator is typically a bank of high power MOSFETS mounted
on an appropriate heat sink with over-temp protection.
The
control system
provides the interface to the supply and provides various protection
circuits for the laser diode.
