Sanyo EP93F manual LC72723/M, LC72720Y/YV

Models: EP93F

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:CCB is SANYO's original bus format. All bus addresses are managed by SANYO for this format.

RDS Demodulator ICs

LC72723/M

Overview

The LC72723 and LC72723M are Radio Data System (RDS) demodulation and signal-processing ICs.

These ICs integrate a bandpass filter, the demodulation circuit, and data buffer RAM on the same chip and allow the RDS data to be read out in slave mode operation with an externally provided clock input signal.

(Master mode operation, in which the data is output in synchronization with the internal RDS clock output, is also supported.)

Functions

Bandpass filter: switched capacitor filter (SCF)

RDS demodulation: 57 kHz carrier regeneration, clock regeneration, biphase and differential decoding

Buffer RAM: 128 bits (about 100 ms)

Data I/O: Data readout in either master or slave mode

RDS ID detection: Supports ID reset

Standby mode: The crystal oscillator is stopped

Fully adjustment free

Packages:(LC72723) : DIP16(300mil)

(LC72723M) : MFP16(225mil)

Block Diagram

+5V

VREF

FLOUT

CIN

+5V

Vdda

 

 

 

Vddd

 

 

 

 

CLOCK

Single-Chip RDSDS SignalSignal--ProcessingProcessingSystemSystem ICIC

LC72720Y/YV

Overview

The LC72720Y and LC72720YV are single-chip system ICs that implement the signal processing required by the European Broadcasting Union RDS (Radio Data System) standard and by the US NRSC (National Radio System Committee) RDBS (Radio Broadcast Data System) standard. These ICs include band-pass filter, demodulator, synchronization, and error correction circuits as well as data buffer RAM on chip and perform effective error correction using a soft-decision error correction technique.

Functions

Band-pass filter: Switched capacitor filter (SCF)

Demodulatior: RDS data clock regeneration and demodulated data reliability information

Synchronization: Block synchronization detection (with variable backward and forward protection conditions)

Error correction: Soft-decision/hard-decision error correction

Buffer RAM: Adequate for 24 blocks of data (about 500 ms) and flag memory

Data I/O: CCB interface (power on reset)

Features

Error correction capability improved by soft-decision error correction

The load on the control microprocessor can be reduced by storing decoded data in the on-chip data buffer RAM

Two synchronization detection circuits provide continuous and stable detection of the synchronization timing

Data can be read out starting with the backward-protection block data after a synchronization reset

Fully adjustment free

Low voltage (supply voltage: 3.0 V min) type

Operating power-supply voltage: 3.0 to 3.6 V

Operating temperature: -40 to +85°C

Packages: (LC72720Y) : DIP24S(300mil)

(LC72720YV) : SSOP30(275mil)

Block Diagram

 

 

 

+

PLL

RECOVERY

 

 

REFERENCE

 

-

(57kHz)

 

 

 

(1187.5Hz)

 

 

VOLTAGE

 

 

 

 

Vssa

 

 

 

 

Vssd

 

 

VREF

 

 

 

 

 

 

 

 

 

 

57kHz

 

 

 

 

MPXIN

ANTIALIASING

BPF

SMOOTHING

 

DATA

RDDA

(SCF)

 

 

FILTER

FILTER

 

DECODER

 

 

 

 

RDCL

 

 

 

 

 

 

 

 

 

 

 

RAM

MODE

 

 

 

 

 

(128 bit)

 

 

 

 

 

 

 

 

 

CLK(4.332MHz)

 

RST

 

 

 

 

RDS-ID/

TEST

TEST

 

 

 

RDS-ID

 

 

 

READY

 

 

 

 

OSC

DETECT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

XIN

XOUT

 

 

+3.3 V

 

VREF

FLOUT

CIN

 

 

 

 

Vdda

 

 

 

+

 

 

CLOCK

 

 

 

 

PLL

 

 

REFERENCE

 

 

-

(57kHz)

RECOVERY

 

 

 

(1187.5Hz)

Vssa

VOLTAGE

 

 

 

 

 

 

VREF

 

 

 

 

 

 

 

 

 

 

 

 

 

57kHz

 

 

 

 

 

 

MPXIN

ANTIALIASING

BPF

SMOOTHING

 

 

 

DATA

(SCF)

 

 

 

 

FILTER

FILTER

 

 

DECODER

 

 

 

 

DO

 

 

RAM

ERROR CORRECTION

 

 

 

CL

CCB

 

SYNC/EC CONTROLLER

(24 BLOCK DATA)

(SOFT DECISION)

DI

 

 

 

 

 

 

 

CE

 

 

 

 

 

 

 

 

T1

 

MEMORY CONTROL

CLK(4.332MHz)

 

 

 

TEST

 

 

SYNC

 

SYNC

T2

 

 

 

 

 

 

 

 

 

DETECT-1

DETECT-2

T3 to T7

 

 

 

OSC/DIVIDER

 

 

 

 

 

 

 

 

 

 

XIN

XOUT

 

 

 

+3.3 V

Vddd

Vssd

RDS-ID

SYNC SYR

 

71 Car Audio

72 Car Audio

 

 

 

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Sanyo EP93F manual LC72723/M, LC72720Y/YV