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CONTROL PANEL
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5.4.2 LED display circuit
Method of LED display
Example: Displaying “COPY”
Fig. 5-6
The transistors (Q3 and Q1) are turned ON when the COM1 signal becomes Low level.
Also, when OUTP7 signal changes to Low level, the current flows from +5.1VA via the transistor (Q1) to
the LED10 (COPY) to turned ON the LED10.
Conditions to turn ON the LED
1. The transistor (Q1) connected to the LED anode is ON.
2. The transistor (Q11) connected to the LED cathode side is ON.
The LED is turned ON when 1) and 2) are satisfied.
Low
Low
(COPY)
LED10
G
Q11
Q1
+5.1VA
SG
SG
Q3
COM1
OUTP7
Current