5. Circuit Descriptions
5-11. Key Scan and Display Circuit
1) Key Scan and display operation.
The model uses a decorder IC which 4 inputs and 9 outputs.
If the IC 9 decorder (TC4028BP) received signals from
MICOM pins (3 6), an output signal per 2 miliseconds
∼
comes out from Q3, Q41, Q8, Q6, Q9, Q7, Q0, Q2, and Q4
pin in sequence. This signal enters to a driver IC input
terminal of the CoolSelect ZoneTM PCB and IC5 (TD
62783AP), then approximate 11V peaks will generate from
an output terminal as shown on the next page.
80