FEATURES

 Power Supply Voltage VPS Range: 5V ∼ 14V

 Full Swing Output Voltage: 0.2VVPS to 0.8VVPS

(input voltage)

 Maximum Output Current: 4A

 High Efficiency: ≥90 - no heat sink is needed

(IOUT=4A@VLDA=10V & VVPS=14V)

 Wide Modulation Bandwidth: DC ∼ 4kHz

 Dual Independent Current Set Ports

 Direct Digital Modulation Control

 Three Control States: Shutdown, Standby and Operation

 Low Output Current Noise: 6.07μAP-P @0.1Hz~10Hz

 High Current Stability: < ±600μA@4A &‒20°C~80°C

 Low Output Ripple Voltage: < 6mV@500kHz

 Fully Shielded

 Both DIP and SMT Packages Available

 Compact Size: 27.4×21×5.7 (mm)

 100 Lead (Pb)-free and RoHS Compliant

DESCRIPTION

This laser driver, ATLS4A214, is an electronic module that

has all the valuable and important, but often difficult to

achieve simultaneously, features simultaneously: wide input

and output voltage range, high output current capability,

high efficiency, low output noise (but it has an output 4mVpp

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 4A well controlled

current at high efficiency. The extremely low noise between

DC ~ 4kHz and low DC current drift make it ideal for driving

diode pumped single mode laser diodes to achieve mode-hopfree

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 ATLS4A214D.

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 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 ATLS4A214 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