IC-HK_1 Datasheet, PDF (6/13 Pages) IC-Haus GmbH – 155MHz LASER SWITCH

iC-HK
155MHz LASER SWITCH
Im_av = 10µA. RM is thus set to ca. 50kS and CI to
50nF. The use of CM is recommended at 100kHz.
This is set to 20pF.
The oscillogram on the right gives the probable
response of the optical laser power with respect to
the power supply and inputs EN1 and EN2.
Rev 21.11.01, Page 6/13
Fig. 13: Optical laser power for Example 4
Example 5: Switching between two levels (50mA and 250mA) with control to the mean by iC-WK
VCC
LDA
TRANSIENT
PROTECTION
1D
NQ
R
-
+
iC-WK
MDK
MDA
VREF
0.5V
CI
LDK
OVERCURRENT
FEEDBACKMON./
OVERTEMP.
GND
AGND
LDK
VDD
CI
EN1
EN2
AGND1
AGND2 GND
Fig. 14: Switching between two levels with control to the mean by iC-WK
By connecting one of the two ENx inputs (here, EN1)
to VDD the corresponding channel is permanently
switched on, producing a bias current. Via the second
input (EN2) the other channel can be pulsed. The bias
and the pulse currents cumulate at pin LDK. Figure 15
gives the possible response of the optical laser power
and the voltages at CI and MDA with reference to the
power supply and inputs EN1 and EN2.
The dimensioning of RK1, RK2 and voltage V(CI) is
similar to Example 2.
Fig. 15: Optical laser power for Example 5