FEATURES

? Wide Input Voltage Range: 4.5V ～15V

? Wide Output Voltage Range: 0.2VVPS to 0.8VVPS (input

voltage)

? Maximum Output Current: 2A

? High Efficiency: ≥92 - no heat sink is needed

(IOUT=2A@LDA=10V&VVPS =15V)

? Wide Modulation Bandwidth: DC ～10kHz

? Dual Independent Current Set Ports: LISH and LISL

? Direct Digital Modulation Control: PCN

? Three Control States: Shutdown, Standby and Operation

? Low Output Current Noise: 4.39μAP-P @0.1Hz ~ 10Hz

? High Current Stability: <250μA@2A &?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, ATLS2A212, is an electronic module that

has all the valuable and important, but often difficult to

achieve simultaneously, features: wide input and output

voltage range, high output current capability, high efficiency,

low output noise (but it has an output 4mVp-p ripple voltage at

500kHz), wide modulation bandwidth, and small size. The

wide output voltage range, 0.2VVPS ~ 0.8VVPS, allows driving

one or multiple serial laser diodes at the same time, for up to

2A 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 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 ATLS2A212D.

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 driver 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 works

except the output stage, see Figure 4. Under Shutdown mode,

all the components of the laser driver stops working and the

power supply current is reduced to < 3μA.

This laser driver generates a high accuracy high stability low

noise, 5μVP-P, <1μVRMS, <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 ATLS2A212 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

around 500kHz.