Mic ETS2228, Руководство по обслуживанию

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ETS2228 Maintenance Manual
All right reserved Page 12, Total 43
6~13 DATA BUS DB0~ DB7
14
Power supply
VDD
15 Ground VSS
16 VOUT
17 CAP3P
18 CAP1N
19 CAP1P
20 CAP2P
21 CAP2N
22
DC/DC voltage converter.
CAP4P
23 V4
24 V3
25 V2
26 V1
27
This is a multi-level power supply for the liquid crystal drive. The voltage Supply applied is
determined by the liquid crystal cell, and is changed through the use of a resistive voltage divided
or through changing the impedance using an op. amp. Voltage levels are determined based on Vss,
and must maintain the relative magnitudes shown below.
V0 ≧ V1 ≧ V2 ≧ V3 ≧ V4 ≧ Vss
V0
List 2 Lattice LCD Signals

Keypad unit
In the ETS2288 series FWTs, the keypad is a peripheral component. If it is broken, it can be
directly replaced. And 72PIPU veneer uses 5×5 keypad
。