iC-WK, iC-WKL
2.4 V CW LASER DIODE DRIVER
Rev D1, Page 2/8
DESCRIPTION
The iC-WK/L device is a driver for laser diodes in con-
tinuous wave operation which requires only four ex-
ternal components. The wide power supply range of
2.4 to 6 V and the integrated reverse battery protec-
tion allow for battery operation with a minimum of two
cells. A reversed battery connection destroys neither
the iC nor the laser diode.
The iC includes integrated circuitry protecting against
destruction by ESD, excessive temperature and over-
current and a soft start which regulates the power
and protects the laser diode when the power supply
is switched on. The iC also filters the laser diode
power supply for transients.
The power supply is regulated and adapted to the
laser diode used by an external resistor at MDA. The
monitor current acts as a reference and is regulated
independent of the influence of temperature and sup-
ply voltage (range: 10 µA to 2.5 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 other types of laser diode configuration;
alternatively, it can be used as an analogue modula-
tion 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 continues
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-WK
offers additional protection by means of spike
detection at pin MDA. Should spikes or oscillation
occur at pin MDA the power lockout is activated.
PACKAGES
SO8, MSOP8 to JEDEC
PIN CONFIGURATION SO8
(top view)
1
8
PIN FUNCTIONS
No. Name Function
LDK
GND
2
7
CI
LDA
1
2
3
4
GND
CI
AGND
MDK
3
6
AGND
4
VCC
5
5 MDA
6 VCC
7 LDA
8 LDK
MDK
MDA
Ground
Capacitance for Power Control
Reference Ground for CI, RM
Monitor Input 2
(MD Cathode, Modulation)
APC Setup,
Monitor Input 1 (MD Anode)
+2.4 to +6 V Supply Voltage
Laser Supply (LD Anode)
Driver Output (LD Cathode)
PIN CONFIGURATION MSOP8
(top view)
1
GND
CI
AGND
MDK
LDK
LDA
VCC
MDA
code...
...
WK
Do not short-circuit pins AGND and GND, for this may
deteriorate the precision of the regulator and interfere
with the soft-start!
iC−WK
Code
ICHAUS [ IC-HAUS GMBH ]
