Sos Detect (D And Pa Board) - Panasonic TH-37PX50U Technical Manual

SOS Detect (D and PA Board)

Figure 38
The SOS detection circuits of the standard definition model TH-42PD50 is similar to the
one used in the high definition models. They are monitored by two microprocessors,
IC4005 of the DG board and IC9003.of the D board. IC4005 of the DG board monitors
for an abnormality detected on the PA and the PB boards. The abnormality may due to
an over-voltage or a short circuit located on the PA or one of the boards powered by PA
board. The SOS input at pin 111 is an active high when an abnormality is detected. The
MPU IC9003 of the D board monitors a variety of SOS inputs. All other SOS conditions
are monitored by IC4005 located on the D board (see fig. 37). Upon detection, the MPU
IC9003 of the D board relates the information to pin 110 (Panel_SOS) of IC4005,
located on the DG board, to trigger the shutdown of the unit.
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