Wavelength Electronics WLD3343, Datasheet And Operating Manual

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© 2018 www.teamWavelength.com 22
WLD SERIES LASER DIODE DRIVERS
ADDITIONAL TECHNICAL
INFORMATION
This section includes useful technical information on these
topics:
• Noise Reduction
• Improve Temperature Coefficient with the WLD3393
Evaluation Board
• Using the WLD3343HB with the WLD3393 Evaluation
Board
• Bandwidth Optimization with the WLD3393
Evaluation board
• Thermal Management Kits
• Prior Revision of the WLD3393 Evaluation Board
• Safe Operating Area Calculation
• WLD3393 Evaluation Board Schematic
NOISE REDUCTION
For lowest noise, operate in Constant Current mode with
the cathode of the laser diode grounded (Type C).
If you buy a special low-noise version of the WLD3343
(WLD3343-2L, or WLD3343-3L for 3 A output), you can
decrease noise by a factor of 2.5 under the same conditions.
Note that you can only operate in Constant Current mode
with the WLD3343-2L and WLD3343-3L.
IMPROVE TEMPERATURE COEFFICIENT WITH
THE WLD3393 EVALUATION BOARD
To achieve better stability, use the external setpoint input
rather than the onboard setpoint trimpot.
USING THE WLD3343HB WITH THE WLD3393
EVALUATION BOARD
To operate with 3.3 V input, use the WLD3343HB. Note that
maximum output current at this supply voltage is 170 mA
(200 mA range) or 1.7 A (2 A range).
BANDWIDTH OPTIMIZATION WITH THE
WLD3393 EVALUATION BOARD
To improve bandwidth, shorten the cables. Expect 1.8 MHz
at 200 mA and 850 kHz at 2 A (sine wave 3 dB point) with
factory-length cables.
POWER SUPPLIES AND NOISE
The WLD drivers deliver stable current with low noise, but
the chosen power supply will directly influence the noise
performance of the driver.
We recommend using a regulated linear power supply for the
best noise performance, but depending on the application
requirements, a switching power supply may be acceptable.
Each case must be evaluated, because a switching power
supply will affect noise, transient, and stability performance.
Wavelength offers several switching power supplies that
may be appropriate.
MODEL MAX VOLTAGE MAX CURRENT
PWRPAK-5V 5 V 8 A
PWRPAK-7V 7 V 3 A
PWRPAK-9V 9 V 3 A
PWRPAK-12V 12 V 2.5 A
Table 12. Available power supplies.
THERMAL MANAGEMENT KITS
The WLD Series of laser diode drivers have customized
thermal kits available. Available kits are:
• WEV300, includes
»
WTW002 thermal washer
»
WHS302 heatsink
»
WXC305 screw kit
• WEV301, includes
»
WTW002 thermal washer
»
WHS302 heatsink
»
5 V fan
»
WXC305 screw kit
• WEV302, includes
»
WTW002 thermal washer
»
WHS302 heatsink
»
12 V fan
»
WXC305 screw kit
PRIOR REVISION OF THE WLD3393
EVALUATION BOARD
The prior revision of the WLD3393 was black. That revision’s
datasheet is available here:
www.teamwavelength.com/download/Datasheets/wld3393b.pdf