IC-WJB Datasheet, PDF (2/12 Pages) IC-Haus GmbH – 2.7 V LASER DIODE DRIVER

iC-WJB
2.7 V LASER DIODE DRIVER
Rev E1, Page 2/12
DESCRIPTION
The iC-WJB device is a driver IC for laser diodes in
continuous or pulsed operation of up to 300 kHz. The
wide power supply range of 2.7 to 6 V and the inte-
grated reverse battery protection allows for battery-
operation with two to four AA/AAA cells.
The laser diode is activated via switching input IN.
A control to the average value of the optical laser
power (APC) and integrated protective functions en-
sure nondestructive operation of the sensitive semi-
conductor laser.
The IC contains protective diodes to prevent destruc-
tion due to ESD, a protective circuit to guard against
overtemperature and undervoltage and a soft-start
circuit to protect the laser diode when switching on
the power supply. Short-term reversed battery con-
nection destroys neither the IC nor the laser diode.
An external resistor at ISET is employed to adapt the
APC to the laser diode being used. The capacitor at
CI determines the recovery time constants and the
starting time.
A watchdog circuit monitors the switching input IN.
If IN remains low longer than preset by the capaci-
tor at CWD, the capacitor of the APC is discharged
at pin CI. This ensures that the current through the
laser diode during the next high pulse at input IN is
not impermissibly high.
PACKAGES SO8, MSOP8 to JEDEC Standard
PIN CONFIGURATION SO8
1
GND
2
CWD
3
CI
4
ISET
8
KLD
7
AMD
6
IN
5
VCC
PIN CONFIGURATION MSOP8
1
GND
CWD
CI
ISET
KLD
AMD
IN
VCC
PIN FUNCTIONS
No. Name Function
1 GND
2 CWD
3 CI
4 ISET
5 VCC
6 IN
7 AMD
8 KLD
Ground
Capacitor for Watchdog
Capacitor for Power Control
Reference Current Input
+2.7 to +6 V Supply Voltage
Input
Anode Monitor Diode
Cathode Laser Diode