1

File Number

3555.6

HSP43124

Serial I/O Filter

The Serial I/O Filter is a high performance filter engine that is

ideal for off loading the burden of filter processing from a

DSP microprocessor. It supports a variety of multistage filter

configurations based on a user programmable filter and fixed

coefficient halfband filters. These configurations include a

programmable FIR filter of up to 256 taps, a cascade of from

one to five halfband filters, or a cascade of halfband filters

followed by a programmable FIR. The half band filters each

decimate by a factor of two, and the FIR filter decimates from

one to eight. When all six filters are selected, a maximum

decimation of 256 is provided.

For digital tuning applications, a separate multiplier is

provided which allows the incoming data stream to be

multiplied, or mixed, by a user supplied mix factor. A two pin

interface is provided for serially loading the mix factor from

an external source or selecting the mix factor from an on-

board ROM. The on-board ROM contains samples of a

sinusoid capable of spectrally shifting the input data by one

function as a digital down converter when the filter stages

are configured as a low-pass filter.

The serial interface for

3- input and output data is compatible

with the serial ports of common DSP microprocessors.

Coefficients and configuration data are loaded over a

bidirectional eight bit interface.

Features

• 45MHz Clock Rate

• 256 Tap Programmable FIR Filter

• 24-Bit Data, 32-Bit Coefficients

• Cascade of up to 5 Half Band Filters

• Decimation from 1 to 256

• Multiplier for Mixing or Scaling Input with an External

Source

• Serial I/O Compatible with Most DSP Microprocessors

Applications

• Low Cost FIR Filter

• Filter Co-Processor

• Digital Tuner

Block Diagram

Ordering Information

PART NUMBER

TEMP.

PACKAGE

PKG.

NO.

HSP43124PC-45

0 to 70

28 Ld PDIP

E28.6

HSP43124PC-33

0 to 70

28 Ld PDIP

E28.6

HSP43124SC-45

0 to 70

28 Ld SOIC

M28.3

HSP43124SC-33

0 to 70

28 Ld SOIC

M28.3

HSP43124SI-40

-40 to 85

28 Ld SOIC

M28.3

DIN

SCLK

SYNCIN

MXIN

SYNCMX

DOUT

SYNCOUT

CLKOUT

CONTROL

INTERFACE

HALF

BAND

FILTER

#5

HALF

BAND

FILTER

#2

HALF

BAND

FILTER

#1

Data Sheet

May 1999

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

http://www.intersil.com or 407-727-9207