IC-HT Datasheet, PDF (34/42 Pages) IC-Haus GmbH – DUAL CW LASER DIODE DRIVER

iC-HT
DUAL CW LASER DIODE DRIVER
START-UP
preliminary
Rev A1, Page 34/42
Setting pin NSTBY to lo iC-HT enters standby mode.
In stand by mode and with no supply voltage at pin
VDD and the current consumption on VB is reduced to
less than 10 µA (cf. Electrical Characteristics No. 002).
of the laser enable pins (EC1, EC2). During this time
(Ten), EC1 and EC2 are ignored and laser cannot be
switched on (cf. Electrical Characteristics No. 111). Af-
ter this time (Ten), laser channels can be switched on.
After wake-up (pin NSTBY rising edge), the internal
regulated supply VDD is generated again. The re-
quired time Tvdd depends on the capacitor connected
to the VDD pin (cf. Electrical Characteristics No. 504).
Once the VDD voltage level is correct, iC-HT enters an
offset compensation procedure regardless of the state
The switch-on procedure needs an initial time (Tci) to
reach the 80 % of the target light power (in APC mode)
or laser current (in ACC mode) (cf. Electrical Char-
acteristics No. 112) and an additional time (Tcio) to
reach the 99 % of the value (cf. Electrical Characteris-
tics No. 113 ). Figure 19 illustrates an startup example
for channel 1 in iC-WK mode.
TVdd
Ten
Tci
Tcio
NSTBY
VDD
VDDOK
EC1
I(LDK1)
Figure 19: Startup timing diagram