3.8 Over-temperature-protection of the LDC2xx
LDC2xx / page 22
Connect the modulation source to the ja ck "MOD IN" (R1). Avoid ground loops when
connecting the function generator.
The laser diode current "I
LD
" can be supervised at the analog output "CTL OUT" (R2)
(refer to chapter 3.1.4).
If the injection current "I
LD
" reaches the set current limit "I
LIM
" in operation the LED
"LIM" (L7) lights up, a beep is given as short warning signal and the laser current is
limited to the value of the current limit "I
LIM
".
If the injection current "I
LD
" is limited by the se lected current limit "I
LIM
" ripple and
noise do no longer correspond to the specif ications for normal operation (refer to
chapter 6.3). However the set maximum current "I
LIM
" cannot be exceeded.
3.8 Over-temperature-protection of the LDC2xx
The laser diode controllers LDC205(B), LDC210(B) and LDC220 have an automatic
over-temperature-protection. If overheated by operating
errors or high ambient
temperatures the current out put of the module is swit ched off automatically. LED
"ERR" (L6, B- version only), lights up and the beeper gives a short warning signal.
The current through the laser diode is swit ched off immediately. Pressing key "ON"
(L9) has no effect in this case.
When the temperature withi n the unit has dropped for about 10 °C the LED "ERR"
(L6) extinguishes and the laser current output can be switched on again.