Crown MARCO-TECH 5000VZ User Manual page 14

Notes
Also tapping in to the ODER output control of LS bias feed and Voltage
Translator feed are signáis from the fault, power (turn-on delay), and
power loss (brown-out) circuits. By using the output of ODER for ±LL
and ±LH control, these sources can mute the audio to the ouíput stage:
a. until power-up delay has timed out; b. immediately upon indication
of any failure mode; c. and immediately upon loss of AC mains (power-
down or actual loss of AC service).
±TEMP signáis are produced by U500 and U501 on the output modules.
U108, on the main module, is a buffer which drives the temperature
sense test point. U117A hasafixed window voltage of 6.2VviaZener
D129. If heatsink temperature level exceeds about 130°C U117A
output will cause both the positiva and negative ODER amplifiers to go
into hard ODER limiting. When the thermal condition clears this ümiting
condition will also clear.
+VCC enters via dual PNP transistor pack U116. Positive ODER bias
isadjustedbyR182. The voltage atthat point controls thestatic balance
of the U116 device. U116 combines the VCC and output current sense
information, the output of which represents output power level. The
common output is brought into RN101 where it provides the reference
for temperature and power. U112B is the active device and, together
Positive ODER
-15V
C130
0.1
14-MA-5000VZ