IC-WKM Datasheet, PDF (2/9 Pages) List of Unclassifed Manufacturers – M-TYPE CW LASER DIODE DRIVER

iC-WKM
M-TYPE CW LASER DIODE DRIVER
preliminary
Rev C1, Page 2/9
DESCRIPTION
iC-WKM is a driver for laser diodes in continuous
wave operation with laser currents of up to 350 mA,
which requires only four external components. The
wide power supply range of up to 15 V allows for op-
eration of blue laser diodes, e.g. by Nichia or Sanyo.
The driver is optimised for M-type laser diodes and
allows the operation from a single supply and the
connection of the laser diode case (common cath-
ode) with ground.
The iC includes integrated circuitry protecting against
destruction by ESD, excessive temperature and over-
current plus a soft start of the regulator to protect the
laser diode when the power supply is switched on.
The iC also filters the laser diode power supply for
transients.
The regulator is adapted to the laser diode by an ex-
ternal resistor at MDA. The monitor current acts as
a reference and is regulated independent of the in-
fluence of temperature and supply voltage (range:
2.5 µA to 6.25 mA). The capacitor at CI determines
the control time constants and start-up time.
A second monitor input, pin MDK, allows the driver
to be used for P-type laser diode configuration; alter-
natively, it can be used as an analogue modulation
input (DC to a few kHz).
In the event of failure, such as overcurrent in the laser
path with a lack of feedback, for example, a quick
power lockout is activated. The shutdown persists
until power is reapplied, permitting a restart. The
strain on power packs and batteries is relieved and
the laser class is retained even in the event of a dis-
turbance.
iC-WKM offers additional protection by means of
spike detection at pin MDA. Should spikes or oscilla-
tion occur at pin MDA the power lockout is activated
after a certain time-out.