IC-WJBEVALWJ1D ICHAUS [IC-Haus GmbH], IC-WJBEVALWJ1D Datasheet - Page 9

• Manufacturer Part Number: IC-WJBEVALWJ1D
• Description: 2.7 V LASER DIODE DRIVER
• Manufacturer: ICHAUS [IC-Haus GmbH]

Furthermore, the introduction of the watchdog permits
long pulse pauses and activation of the laser diode with
pulse packets.
CW Operation
In case of CW operation, the input IN can be con-
nected to the power supply VCC. The pin CWD may
be left open, because the capacitor for the watchdog
is not necessary. The capacitor CI for the averaging
control can be reduced to 100 nF.
Operation of laser diode via cable
It is recommended to connect a capacitor of 1 to 10 nF
across the laser diode in order to protect the laser
diode against destruction due to ESD or transients.
This capacitor should be placed close to the laser
diode and not at the beginning of the LD supply line.
An approx. 2
the IC power consumption and damps possible reso-
iC-WJB
2.7 V LASER DIODE DRIVER
100nF
CI
15kΩ
RSET
2.7..6V
1
2
3
4
series resistor at pin KLD reduces
GND
CWD
CI
ISET
WDOG
REF
iC−WJB
S1
Figure 10: CW operation via cable plus protective circuitry
VCC
KLD
AMD
IN
R2
2Ω
8
7
6
5
ZD6V8
0..2Ω
R1
100nF
C2
D1
nances of the load circuit caused by the inductive LD
supply line. This resistor is useful for many applica-
tions, also for those which do not operate via cable.
On a PCB the forward path VCC to the laser diode
should be arranged in parallel with the return path to
KLD even when the line is only a few centimeters in
length.
Additional protective components for clipping of strong
positive and negative spikes can be useful, in particu-
lar when contact bouncing occurs in an inductive accu-
mulator power supply line. Elements which come into
question here are D1 and R1 as in Figure 10.
C1
47uF
LD supply cord
KLD
AMD
VCC
C3
4.7nF
LD
Rev E1, Page 9/12
MD