7-4
2.4 DC to DC
The required power supply is different for each chip, and the voltage of 12v, and 5v offered by PWPC can’t
reach the requirement, so we deal with this problem by means of two pieces of DC TO DC chips(AIC1084,
BS1834). The circuit diagrams are as follows:
5V TO 3.3V
5V TO 1.8V
2.5
Panel Control Circuit
The high level output from PIN 30 of U101 makes Q105, Q104 break through, and offer 3.3V to panel when
work well. The output is low level when it’s saving energy state and Q105, Q104 break off, so the panel doesn’t
work.
Active high
PANEL
power select