RESET
(Active Low,
TTL compatible
VDD
GND
LDC1
LDC1
LDC2
LDC2
PWR GND
(for LD V
S
)
PWR GND
(for LD V
S
)
V
SET
1
V
SET
2
(Impedance:
2kΩ per driver,
1kΩ when
paralleled)
GND
(forV
SET
)
V
S
LD
VDD
SAFETY INFORMATION
SAFE OPERATING AREA — DO NOT EXCEED
INTERNAL POWER DISSIPATION LIMITS
Before attempting to operate the FL500 driver, it is imperative
that you first determine that the unit will operate within the
Safe Operating Area
(SOA). Operating outside of the SOA
may damage the laser and the FL500. Operating outside of
the SOA will void the warranty.
To determine if the FL500 driver will be operating in the
safe range in your application, consult the instructions for
calculating the Safe Operating Area online:
www.teamwavelength.com/support/design-tools/soa-ld-calculator/
SOA charts are included in this datasheet for quick reference
(
), but we recommend you use the online tools
instead.
T
o
ensure
safe
operaTion
of
The
fL500
Driver
,
iT
is
imperaTive
ThaT
you
DeTermine
if
The
uniT
is
going
To
be
operaTing
wiThin
The
inTernaL
heaT
DissipaTion
s
afe
o
peraTing
a
rea
(soa).
If you have any questions about the Safe Operating Area
calculator, call the factory for free and prompt technical
assistance.
PREVENT DAMAGE FROM ELECTROSTATIC
DISCHARGE
Before proceeding, it is critical that you take precautions to
prevent electrostatic discharge (ESD) damage to the driver
and your laser. ESD damage can result from improper
handling of sensitive electronics, and is easily preventable
with simple precautions.
For more information regarding ESD, see Application Note
AN-LDTC06: Basics: Electrostatic Discharge (ESD).
We recommend that you always observe ESD precautions
when handing the FL500 driver and your laser diode.
!
THEORY OF OPERATION
The FL500 driver is a controlled current source: it delivers
the current commanded by the setpoint. The current source
continually monitors the actual output current, compares it to
the setpoint, and adjusts the current if there is a difference
between the two signals.
It may be useful to remember that you do not directly set the
driver current setpoint; instead, you adjust a voltage signal
that represents the output current. The voltage and output
current are related by a transfer function that varies by driver
capacity. The setpoint voltage is adjusted with an external
input.
As current is driven through the load, there is a voltage drop
across the load because of the impedance. As the current
increases, the voltage drop may increase to the point that it
reaches the Compliance Voltage limit of the current source.
Once that occurs, the current source is no longer able to
increase the current driven to the load even if you increase
the setpoint.
shows the block diagram of the FL500.
The FL500 driver includes features that help protect your
laser and make the driver more versatile in a wide array of
applications: handheld devices, airborne applications, and
spectroscopy systems.
Figure 6. FL500 Block Diagram
© 2020
7
FL500 LASER DIODE DRIVER
