ATLS1A102 Datasheet, PDF (1/6 Pages) List of Unclassifed Manufacturers – Low Noise Constant Current Laser Driver

Low Noise Constant Current Laser Driver
Analog Technologies
ATLS1A102
FEATURES
Ultra Low Noise: <10µA*
High Current without Heat Sink: 1A
High Absolute Accuracy: <0.1%
High Stability: 100ppm/°C
Dual Modulation Ports: High/Low Speed
Low Drop Out Voltage: 1V
Complete Shielding
Compact Size
SMT Package Available
*Total RMS between 0.1Hz to 0.5MHz.
APPLICATIONS
Driving diode lasers with low noise, including DPSSLs,
EDFAs, fiber lasers, diode laser modules, etc.
DESCRIPTION
The ATLS1A102 is an electronic module designed for
driving diode lasers with up to 1A low noise current. The
output voltage is 1.5V to 4V when powered by a 5V power
supply.
The ATLS1A102 has two input ports for modulating the
output current: one for low speed of up to 0.08Hz bandwidth
and the other high speed modulation of up to 300KHz. The
former is for CW (Continuous Wave) operation and the
latter is for modulated operation.
A high stability low noise 2.5V reference voltage is
provided internally for setting the output current. This
reference can also be as the voltage reference for external
ADCs (Analog to Digital Converters) and DACs (Digital to
Analog Converters), which might be used for monitoring
and/or setting the laser current.
The shut down pin can turn the controller electronically
without disconnecting the power supply.
There is an output port, LIO (pin 11), dedicated for
monitoring the laser current. It can be connected to an ADC
or a voltmeter.
The control loop is monitored in real time by an internal
circuit, to make sure that it works properly. The monitoring
result is sent to the LPGD node (pin 12). When this pin is
pulled up internally, it indicates that the loops works fine.
By default, the maximum output current is set to 1A. This
value can be altered by external circuit which is shown in
the application section.
The ATLS1A102 is packaged in a 6 sided metal enclosure,
which blocks EMIs (Electro-Magnetic Interferences) to
prevent the controller and other electronics from interfering
each other.
SDN 1 12 LPGD
GND 2 11 LIO
2P5V
LISL
3
4
10
9
VPS
PGND
19.4
P5V 5 8 LDA
LISH 6 7 LDC
14.5
Figure 1 Pin Names and Locations
The controller has 2 types of mounting packages: through hole
and surface mount. The latter saves PCB space the controller
takes.
Figure 1 is the actual size top view of the ATLS1A102D,
which shows the pin names and locations. Its thickness is 5mm.
SPECIFICATIONS
Maximum output current:
1A
Output current noise:
(0.1Hz to 0.5MHz RMS)
<10µA
Low speed current set voltage:
(on LISL pin)
0 to 2.5V
High speed current set voltage:
(on LISL pin)
0 to 0.5V
Low speed modulation cut-off frequency: 0.08Hz
High speed modulation cut-off frequency: 300KHz
Power supply voltage range:
4.5V to 5.5V
Thermal resistance:
60°C/W (free air)
30°C/W (PCB mount)
Operating temperature:
−25°C to 85°C
OPERATION PRINCIPLE
Figure 2 is the block diagram of the controller.
SDN
1
GND
2
LISL
4
P5V
5
LISH
6
100nF
Low
Pass
Filter
100KΩ
Linear
Mode
Driver
VPS
10
PGND
9
LDA
8
Laser
Diode
Control
Unit
Current
Sense
LDC
7
Figure 2 Block Diagram
55 0 E. W eddell Drive, Suit e 4 , Sunnyvale, CA 9 4089 , U. S. A . Tel.: [phone] , Fax: (408 ) 7 47-977 0, Web: w w w .analogt echnologies.com
Copyrights 2000 – 2005, Analog Technologies, Inc. All Rights Reserved. Updated on 3/29/2007.
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