iC-VJ, iC-VJZ
LASER DIODE CONTROLLER
Rev A1, Page 8/10
up transients (Fig. 7). This capacitor should be placed
close to the laser diode and not at the start of the LD
supply line.
VCC [2V/div]
LASER Output [1mW/div]
An approx. 12 Ω series resistor at pin KLD reduces
the iC power consumption and damps possible reso-
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.
C [50mV/div]
Figure 6: Turn-off behavior
Operation of a laser diode via cable
When the LD supply line is laid out on the PCB, the
It is recommended to connect a capacitor from 1 nF up forward path VCC should be arranged in parallel with,
to 10 nF across the laser diode in order to protect the i.e. be close to the return path to KLD, even when the
laser diode against destruction due to ESD or build- line is only a few centimeters in length.
Sync
DC−Monitor
5V
R3
C3
C4
10kΩ
100nF
100µF
13
4
12
MI
MO
VCC
DRIVER
OUTPUT
DIVIDER
16:1
Q
1
LD
14
15
PRF
C5
NQ
5nF
MD
NQ
AMD
1
MONITOR
NPRF
4
7
2
1:1 iC−VJ
1:3 iC−VJZ
R5
12Ω
POWER ON
TH.− SHUTDOWN
REFERENCE
KLD
2
3
OSCILLATOR
GND
3
5
6
R
RC
6
ISET
11
AGND
7
iC−VJ/VJZ CI
5
9
R1
800Ω
RSET
C2
470nF
C1
100pF
Figure 7: Operation of a laser diode via cable
ICHAUS [ IC-HAUS GMBH ]
