PT2240B View Datasheet(PDF) - Princeton Technology

Part Name

Description

Manufacturer

PT2240B

Encoder IC

Princeton Technology 

PT2240B

FUNCTION DESCRIPTION

PT2240B encodes the address code and data set at D0 ~ D3 and A0 ~ A19 into a special waveform and outputs it to the

DOUT. This waveform is fed to the RF modulator for transmission.

CODE BITS

A Code Bit is the basic component of the encoded waveform, and can be classified as either an (Address/Data) Bit or a

SYNC (Synchronous) Bit.

ADDRESS/DATA BIT WAVEFORM

An Address/Data Bit can be designated as either Bit “0” or “1” if it is in High or Low State respectively. One bit waveform

consists of one pulse cycle and each pulse cycle has 128 oscillating time periods. For further details, please refer to the

diagram below:

where the oscillating time period, α=1/f and (f is the oscillation frequency)

As you can see in the diagram above, Bit “0” consist of a “High“ Pulse for 32α (where α=oscillating time period) then

changes to “LOW” Pulse for 96α. Likewise, for Bit “1”, the “High” Pulse for 96α is followed by “Low” Pulse for 32α.

SYNCHRONOUS (SYNC.) BIT WAVEFORM

The Synchronous Bit Waveform is 8 bits long with 1/32 bit width pulse. Please refer to the diagram below:

V1.2

4

September, 2009

Share Link: