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5
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LCX032ANB
Level Conversion Circuit
The LCX032ANB has a built-in level conversion circuit in the clock input unit located inside the panel. The
circuit voltage is stepped up to V
DD
inside the panel. This level conversion circuit meets the specifications of a
3.0V power supply of the externally-driven IC.
1. I/O characteristics of level conversion circuit
(For a single-phase input unit)
An example of the I/O voltage characteristics of a level
conversion circuit is shown in the figure to the right.
The input voltage value that becomes half the output
voltage (after voltage conversion) is defined as Vth.
The Vth value varies depending on the V
DD
voltage.
The Vth values under standard conditions are
indicated in the table below. (HST, VST, EN, DWN,
STB, RGT, VCK and BLK in the case of a single-phase
input)
V
DD
= 12.0V
V
DD
2
V
DD
Vth
Input voltage [V]
Example of single-phase
I/O characteristics
O
Item
Vth voltage of circuit
Vth
0.35
1.50
2.60
V
Symbol
Min.
Typ.
Max.
Unit
(For a differential input unit)
An example of I/O voltage characteristics of a level
conversion circuit for a differential input is shown in
the figure to the right. Although the characteristics,
including those of the Vth voltage, are basically the
same as those for a single-phased input, the two-
phased input phase is defined. (Refer to clock
timing conditions.)
V
DD
2
V
DD
Vth
Input voltage [V]
Example of differential I/O
characteristics
O
2. Current characteristics at the input pin of level conversion circuit
A slight pull-in current is generated at the input pin
of the level conversion circuit. (The equivalent
circuit is shown to the right.) The current volume
increases as the voltage at the input pin decreases,
and is maximized when the pin is grounded. (Refer
to electrical characteristics.)
V
DD
output
HCK1
input
HCK2
input
Level conversion equivalent circuit
0
0
Max. value
Input pin voltage [V]
10
Pull-in current characteristics at the input pin
I