FEATURES

 Wide Input Voltage Range: 8.5V ∼40V

 Wide Output Voltage Range: 0.1×VVPS to 0.8×VVPS

(input voltage)

 High Current Capability: 25A

 High Efficiency: ≥95%

(IOUT=25A@VLDA=30V&VVPS=40V)

 Wide Modulation Bandwidth: DC ∼ 10kHz

 Compact Size: 63.0(L) × 61.0(W) × 16.7(H) (mm)

 Dual Independent Current Set Ports: LISH and LISL

 Direct Digital Modulation Control: PCN

 Three Control States: Shutdown, Standby or Operation

 Low Output Current Noise: <20μAP-P@0.1Hz~10Hz

 High Current Stability: <±20mA@25A&(‒20°C~80°C)

 Low Output Ripple Voltage: <10mVP-P@500kHz

 Fully Shielded

 100 % Lead (Pb)-free and RoHS Compliant

DESCRIPTION

This laser driver, ATLS25A219CH, 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 10mVp-p ripple voltage at 500kHz),

wide modulation bandwidth, and small size. The wide output

voltage range, 0.1×VVPS ~ 0.8×VVPS, allows driving one or

multiple serial laser diodes at the same time, for up to 25A well

controlled current at high efficiency. The extremely low noise

between DC 0.1Hz ~ 10Hz and low DC current drift make it ideal

for driving high current laser diode arrays. Because of the high

efficiency, the build-in small heat sink is sufficient to dissipate

the heat generated by the driver, no additional heat sink is

needed. 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 foot print of this laser driver saves

valuable space for the laser system. Figure 1 shows physical

photo of the ATLS25A219CH.

This laser driver has two current set ports which can digitally be

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 is

monitored by dedicated port. 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 well.

The laser driver has 3 states: Operation, Standby and Shutdown.

Under Standby mode, all the laser driver components will be

working 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 < 2mA.

This laser driver generates a high accuracy high stability low

noise. When outputting 25A to the laser, the noise current is

20μAP-P, noise voltage at the output node, LDA, is <2μVRMS,

output current stability is <100ppm/°C. It comes with a low

noise high stability voltage reference 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 ATLS25A219CH uses a constant frequency high efficiency

PWM output stage. Its switching signal is taken out through a

buffer at the SYNO port, pin 10, 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.

For noise sensitive applications, please be aware that this laser

driver has very low noise between DC 0.1Hz to 10Hz, but there

is a 500kHz sine-wave ripple voltage, around 10mVp-p, present

at the output, the LDA port.