© 2018
18
WLD SERIES LASER DIODE DRIVERS
Step 5: Install The Laser Diode Configuration
Board
To configure the WLD3393 for your laser diode type, connect
the configuration board to the bottom of the WLD3393 so
that the arrow on the protruding edge of the configuration
board points to either A/B or C. Refer to
for Type
A/B example installation, and
for Type C example
installation.
Type A Laser Diode
Type B Laser Diode
Common
Cathode
Laser Diode Anode &
Photodiode Cathode Common
Isolated Photodiode
Short the
Laser Diode Anode
to Photodiode Cathode
NOTE:
LINE UP
ARROW WITH
LASER TYPE
INDICATED ON
MAIN BOARD
A/B
TYPE
CC
SET
WLD3343
P MON
I MON
COM
PGND
VDD
PDC
PDA
LDC
LDA
WAVELENGTH ELECTRONICS
WLD3393
ONLY
0N
(-)
(+)
FAN
PMON
SET
2.5
PDM
CP
COM
LIM
WITH
ENABLE
VS
IMON
OFF
C
USE
1
Set-Up for
Type A/B
Laser Diodes
Figure 16.
Proper installation of the configuration card for
Type A/B lasers.
Type C Laser Diode
Common
Anode
Laser Diode Cathode &
Photodiode Anode Common
A/B
TYPE
CC
SET
WLD3343
PDC
PDA
LDC
LDA
WAVELENGTH ELECTRONICS
WLD3393
ONLY
0N
(-)
(+)
FAN
PMON
SET
2.5
PDM
CP
COM
LIM
WITH
ENABLE
IMON
OFF
C
USE
1
Set-Up for
Type C
Laser Diodes
P MON
I MON
COM
PGND
VDD
VS
Figure 17.
Proper installation of the configuration card for
Type C lasers.
!
If the WLD3393 is configured incorrectly
for the type of laser diode you are using,
damage can result to your laser diode and/
or the WLD3393.
Step 6: Attach The Heatsink And Fan
This step is optional for less than +5 V, 500 mA operation.
• Heatsink Requirements:
»
Attach a heatsink (WHS302) when the WLD3343
will operate between 500 mA and 1.0 A output
current.
»
Attach a fan (WXC303 for +5 VDC or WXC304
for +12 VDC) to the heatsink for output currents
exceeding 1.0 A.
»
If using Wavelength accessories, refer to the
WHS302, WTW002, WXC303, and/or the
WXC304 datasheets for assembly instructions.
• Fan Connections:
Connect the fan leads to the (+)
and (–) fan power positions on the terminal block and
secure with a small flat head screwdriver. The fan
connects to the V
DD
supply, not V
S
, so care must be
exercised to ensure that the proper fan is selected,
5 VDC or +12 VDC, when using dual power
supplies. Optionally, for lower noise operation, the fan
leads may be connected directly to a separate power
supply compatible with the fan.
Step 7: Attach The V
DD
And V
S
Power Supplies
The WLD3393 has two power supply connections:
• V
S
»
provides power for driving the laser (minimum
current capacity greater than limit current setting).
»
can range from +4.5 to +12 V (except for HB
models, must be b3.3 V and +6 V).
• V
DD
»
provides power to the control electronics
(minimum 100 mA).
»
can range from +5 to +12 V (except for HB
models, must be b3.3 V and +6 V).
V
S
and V
DD
can be connected for simple operation using the
Power Select Jumper. See Step 4 for location.
A separate V
S
power supply allows the output current stage
to operate below the minimum 5 V required for the control
electronics or up to the +12 V maxium (for multiple laser
diodes in series). Select V
S
approximately 2.0 V above the
maximum voltage drop across the laser diode to reduce the
power dissipation in the WLD3343 component and minimize
your heatsinking requirements.
Note that for Type C laser
diodes in Constant Power mode, V
DD
must be greater than
or equal to V
S
to keep the photodiode signal in range.
Use PGND for the power return. The common (COM)
terminal on the WLD3393 is not intended to act as a power
connection, but as the low noise ground reference for
connecting an external VSET source, and for monitoring the
IMON, PMON, and PDM signals.
The 2.5 mm input power jack attaches to V
DD
. You can use
the Wavelength PWRPAK power supplies with this jack. Use
either the power jack or the power inputs on the connector
harness, not both.
