FEATURES
 Power Supply Voltage VPS Range: 4.5V ∼15V
 Full Swing Output Voltage: 0.2VVPS to 0.8VVPS (input
voltage)
 Maximum Output Current: 3A
 High Efficiency: ≥90% - no heat sink is needed
 (IOUT=3A @ VLDA=11V&VVPS=15V)
 Wide Modulation Bandwidth: DC ∼ 10kHz
 Dual Independent Current Set Ports
 Direct Digital Modulation Control
 Three Control States: Shutdown, Standby and Operation
 Low Output Current Noise: < 5.21μAP-P @0.1Hz~10Hz
 High Current Stability: <±300μA@3A &−20°C~80°C
 Low Output Ripple Voltage: <4mV@500kHz
 Fully Shielded
 Compact Size: 25.4×20×5 (mm)
 100 % Lead (Pb)-free and RoHS Compliant
DESCRIPTION
This laser driver, ATLS3A212, is an electronic module that has
all the valuable and important, but often contradict features,
simultaneously: Wide input and output voltage range, high
output current capability, high efficiency, low output noise (but
it has a 4mVP-P ripple voltage at 500kHz), wide modulation
bandwidth, and small size. The wide output voltage range,
0.2VVPS to 0.8VVPS, allows driving one or multiple serial laser
diodes at the same time, for up to 3A well controlled current at
high efficiency. The extremely low noise between DC ~10kHz
and low DC current drift make it ideal for driving diode
pumped single mode laser diodes to achieve mode-hop-free
and narrow optical wavelength drift, thus, long coherent length.
Because of the high efficiency, the laser driver generates small
amount of heat, thus, no heat sink is necessary for normal
operation. The fully shielded case blocks all the incoming and
outgoing EMIs (Electro-Magnet Interferences). Therefore, this
laser will not interfere with other surrounding electronics, nor
will be interfered by them. The small package saves valuable
PCB space in laser systems. Figure 1 shows physical photo of
the ATLS3A212.
This laser driver has two current set ports digitally controlled to
switch between them for setting the output current. This feature
allows modulating the laser digitally with 2 preset current
values.
The actual laser current and laser driver temperature are
monitored by dedicated ports. In case the laser driver
temperature exceeds the limit, 120°C, the laser driver will shut
down the output stage by itself and force the laser drive into
Standby Mode. There is a loop good indication output to tell if
the laser driver works ok.
The laser driver has 3 states: Operation, Standby and Shutdown.
Under Standby mode, all the laser driver components work
except the output stage, see Figure 4. Under Shutdown mode,
all the components of the laser driver stop working and the
power supply current is reduced to < 3μA.
This laser driver generates a high accuracy high stability low
noise, 5μVp-p, 3μVRMS, <8ppm/°C, 2.5V<±2mV, voltage
reference output which can be used for setting the output
current and also be used as the reference voltage for the ADCs
(Analog to Digital Converters) and/or DACs (Digital to Analog
Converters).
The ATLS3A212 uses a constant frequency high efficiency
PWM output stage. Its switching signal is taken out through a
buffer at the SYNO port, pin 14, which can be used by other
switch mode electronics as the trigger signal to avoid
frequency beating interference, if the free-run frequency is near
to 500kHz.