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PT2249A_PT2250A V2.6

- 14 -

May, 2007

Remote Control Receiver IC

PT2249A_PT2250A

APPLICATION NOTE:

1. Combination of PT2248/PT2249A Series Code Bits

a) PT2249A Series Code Bit C1 is internally pulled high and thereby set at a default value of “1”. Thus,

PT2248 Code Bit C1 must be set at “1”.

b) PT2249A Series Code Bits C2 and C3 may be programmed as follows:

1) “0”, “0” (This combination is not available with TC9149.)

2) “0”, “1”

3) “1”, “0”

4) “1”, “1”

c) To set Code Bit to “1” on PT2248, diodes must be connected to Code Terminal from the T1 ~ T3

terminals.

d) To set Code Bit to “0” on PT2248, the terminals must be kept floating, except C1 - add one diode.

e) The Code Bits Combinations of PT2248 and PT2249A Series are shown below:

PT2248

PT2249A Series

C1

C2

C3

C2

C3

1

0

0

0

0

1

0

1

0

1

1

1

0

1

0

1

1

1

1

1

f) Example: (Refer to Example 1 diagram)

The following example shows the case when PT2248 Code Bits C1=1, C2=1, and C3=0. The CODE2

Pin of the PT2249A Series is programmed in floating state and CODE3 pin is connected to Vss (C2=1,

C3=0.) In this way, the PT2249A Series can match the C2, C3 Code Bits of PT2248 and correctly

decode the remote commands.

Example 1

Circuit Diagram when Code Bit C2 = 1 and C3 = 0