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PT2270 V1.3

- 8 -

May, 2006

Remote Control Decoder IC

PT2270

VALID TRANSMISSION

When PT2270 receives a transmission code word, it initially checks whether this is a valid transmission.

For a transmission to be valid, (1) it must be a Complete Code Word, and (2) the Address Bits must

match the Address Setting at the Address Pins. After two consecutive valid transmissions, PT2270 (1)

drives the data pins according to the data bits received, and (2) raises VT to high voltage (high state).

The timings are shown in the following diagram.

1st Word

2nd Word

Sync Bit

Sync Bit

DIN

Data Pins

(Momentary)

VT

2tc

Note: tc=Width of 1 Code Word

LATCH OR MOMENTARY DATA OUTPUT TYPE

PT2270 uses either the latch or the momentary data output type depending on the PT2270 version

used. The latch type (PT2270-Lx) activates the data out during transmission and this data is sustained

in the memory until another data is inputted or entered. A momentary type (PT2270-Mx), on the other

hand, activates the data out only during transmission. In the momentary type, the data does not remain

in the memory after the transmission is completed. Please refer to the diagram below.

Data Words (X)

Data Words (Y)

2tc

2tc

2tc

≤

2tc

≤

Data Output X

Data Output Y

Data Output X

Data Output Y

DIN

VT

DATA PINS

(Momentary)

DATA PINS

(Latch)

Note: tc=Width of 1 Code Word