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LCX005BKB

Level Conversion Circuit

The LCX005BKB has a built-in level conversion circuit in the clock input unit located inside the panel. The

3.0V to 5.0V 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 values under standard conditions are

indicated in the table below. (HST, VST, EN, CLR,

and RGT in the case of a single-phase input)

2

Vth

Input voltage [V]

Example of single-phase

I/O characteristics

Item

Vth voltage of circuit

Vth

0.4

1.50

2.75

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.)

2

Vth

Input voltage [V]

Example of differential I/O

characteristics

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.)

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