FEATURES
 High efficiency: ≥ 76%
 Maximum output current: 45A
 Wide output voltage: 0V ~ 4V
 Wide input voltage: 100VAC ~ 240VAC
 High speed digital modulation: 5kHz
 Configurable output current and voltage limit
 Configurable digital modulation valley current
 Low temperature rise: 30°C
 Over-temperature protection
 Operating temperature: −20°C ~ 50°C
 MBTF (Mean Time Before Failure): 180,000 hours
 The ripple noise at 600kHz: <10mVP-P
 Compact size
 Low cost
 100 % lead (Pb)-free and RoHS compliant

APPLICATIONS
Driving diode lasers with high current and high stability,
such as fiber lasers, diode laser bars, etc.

DESCRIPTIONS
The AAS45A4V2 is an electronic power supply block
designed for driving diode lasers with up to 45A low noise
current. The output current can be set by an analog voltage
of 0V to 2.5V, an external potentiometer, or an internal
potentiometer, to between 0A and 45A.
A pulsed output current can be generated by controlling the
PCN port with a digital signal, under which, the peak output
current is set by the LISH port while the valley output current
is set by the LISL port. The modulation frequency can go up to
5kHz, resulting to an approximately 56μS rise/fall time at the
output current.
The AAS45A4V2 laser driver comes with a high stability low
noise 2.5V reference voltage. It can be used for setting the
output current and maximum output voltage. This reference
can also be used as the voltage reference for external ADCs
(Analog to Digital Converters) and DACs (Digital to Analog
Converters), which might be used for monitoring and/or setting
the laser current and maximum output voltage, the so-called
compliance voltage.
This laser driver block is highly efficient: its efficiency is
≥ 76%. It saves energy and has low temperature rise.
There is an over-temperature protection circuit inside, in case
the laser power supply temperature exceeds the temperature
limit, 85°C, the laser driver will shut down itself and be turned
back on by itself after the temperature returns to the normal
temperature range.
There is a soft-start circuit in this laser driver, which ensures
smooth current transactions during power-up periods.
In case there is a short circuit at the output, the internal
protection circuit will cut off the output.
The output voltage is automatically set from 0V to 4V to keep
the output current at a pre-set value. The maximum voltage can
be set by a potentiometer to between 0V and 4V. When the
output voltage hits this set maximum value, the output voltage
remains to be the maximum value and output current stop
following the set value, the laser driver will be working under
constant voltage mode.
The control loop is monitored in real time by an internal circuit,
to make sure that it works properly. The monitoring result is
sent to the LPGD node. When this pin is pulled up internally, it
indicates that the control loop works properly and Loop Good
LED will be lit. This pin signal can be sent to a microcontroller,
or used for driving an LED through a buffer. The internal
equivalent circuit of this pin is a 5kΩ pull-up resistor in parallel
with an open drain comparator output.
The main specifications are shown in Table 1 below.