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.