sion. This library supports the MPEG 1 sample rates
of 48 k, 44.1 k and 32 k bits per second; the MPEG 2
sample rates of 24 k, 22.05 k and 16 k bits per sec-
ond; and the MPEG 2.5 sample rates of 12 k,
11.025 k and 8 k bits per second. In addition to all
standard fixed compressed data rates, the MPEG
layer 3 object code library also supports decompres-
sion of variable bit-rate data streams.
2
DS453PP2
EP7209
OVERVIEW
(cont.)
Power Management
The EP7209 is designed for ultra-low-power opera-
tion. Its core operates at only 2.5 V, while its I/O has
an operation range of 2.5 V-3.3 V. Through careful
design, Cirrus Logic has achieved extremely low
power consumption with the EP7209. This is
achieved by using a combination of dynamically
adjustable core clock frequencies, low power states
utilized during periods of inactivity, and fully static
design principles. For example, when decompressing
MPEG 1 layer 3 music data with sample rates of
44.1 kHz and 128 kbits/sec, the EP7209 consumes
less than 87 mW. At sampling frequencies of
22.05 kHz and 64 kbits/sec, power consumption falls
to 50 mW.
downloading of compressed music or data from a PC
to an EP7209-based portable digital audio player.
The EP7209 can also be connected to industry stan-
dard USB slave devices through an external inter-
face. The power of the EP7209 coupled with the
36 MHz external data bus ensures that the EP7209
can support rapid transfer of compressed audio data
over a USB interface.
The EP7209 also includes a built-in 115.2 kbps IrDA
SIR protocol encoder/decoder that can be used to
drive an infrared communication interface to down-
load the data.
Digital Audio Interface
The EP7209 integrates an DAI interface to enable a
direct connection to many low cost, low power, high
quality audio converters. In particular, the DAI inter-
face can be used to drive the Crystal CS43L41 / 42 /
43 low power audio DACs and the Crystal CS53L32
low power audio ADC. Some of these devices feature
digital bass and treble boost, digital volume control
and compressor-limiter functions.
Audio Data Memory Interfaces
The EP7209 connects directly to both on-system
FLASH memory and to removable FLASH memory-
cards. The generality of the external interface on the
EP7209 allows for the use of a wide variety of addi-
tional memory types for compressed audio data stor-
age.
LCD Interface
The EP7209 interfaces directly to a single-scan panel
monochrome LCD display. For portable digital audio
player applications that require LCDs, a 128 kbyte
display buffer is provided.
Packaging
The EP7209 is available in a 208-pin LQFP package
and a 256-ball PBGA package.
System Design
As shown in the system block diagram, simply adding
FLASH memory, an LCD, an audio DAC, and some
discrete components, a complete low power digital
audio player system can be made. (See the following
illustration).
Data Download
The EP7209 along with minimal glue logic can con-
nect to a PC through the parallel port. This enables
Contacting Cirrus Logic Support
For a complete listing of Direct Sales, Distributor, and Sales Representative contacts, visit the Cirrus Logic web site at:
http://www.cirrus.com/corporate/contacts/
Preliminary product information describes products which are in production, but for which full characterization data is not yet available. Advance product infor-
mation describes products which are in development and subject to development changes. Cirrus Logic, Inc. has made best efforts to ensure that the information
contained in this document is accurate and reliable. However, the information is subject to change without notice and is provided “AS IS” without warranty of
any kind (express or implied). No responsibility is assumed by Cirrus Logic, Inc. for the use of this information, nor for infringements of patents or other rights
of third parties. This document is the property of Cirrus Logic, Inc. and implies no license under patents, copyrights, trademarks, or trade secrets. No part of
this publication may be copied, reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical, photographic, or
otherwise) without the prior written consent of Cirrus Logic, Inc. Items from any Cirrus Logic website or disk may be printed for use by the user. However, no
part of the printout or electronic files may be copied, reproduced, stored in a retrieval system, or transmitted, in any form or by any means (electronic, mechanical,
photographic, or otherwise) without the prior written consent of Cirrus Logic, Inc.Furthermore, no part of this publication may be used as a basis for manufacture
or sale of any items without the prior written consent of Cirrus Logic, Inc. The names of products of Cirrus Logic, Inc. or other vendors and suppliers appearing
in this document may be trademarks or service marks of their respective owners which may be registered in some jurisdictions. A list of Cirrus Logic, Inc. trade-
marks and service marks can be found at http://www.cirrus.com.
DS453PP2
3
EP7209
OVERVIEW
(cont.)
CRYSTAL
CRYSTAL
MOSCIN
RTCIN
LCD
D[31:0]
A[27:0]
COL[7:0]
PA[7:0]
KEYBOARD/
PUSH BUTTONS
FLASH CARD/
FLASH MEMORY
PC PARALLEL PORT
NMOE
NMWE
EP7209
EINT[X]
CS[3]
SMART MEDIA
CARD
INTERFACE
CS[0]
CS[1]
PE[2:0]
NPOR
NPWRFL
NBATOK
NEXTPWR
NBATCHG
RUN
WAKEUP
POWER
SUPPLY UNIT
AND
COMPARATORS
BATTERY
NOR
FLASH
×
16
PB[6:7]
SSICLK
SSITXFR
SSITXDA
SSIRXDA
HEADPHONES
STEREO DAC
CS43L41 / 42 /
43
NAND
FLASH
×
8
STEREO ADC
CS53L32
MIC
USB
CS[4]
Figure 1. A Typical EP7209-Based Digital Audio Player Reference
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