CIRRUS EP7312-90

Leading the Digital Entertainment RevolutionTM
New ARM720T 90 MHz Embedded Processor
Allows Faster than Real-Time Recording
EP7312-90 Features
ARM720T processor
8 Kbytes of four-way set-associative cache
MMU with 64-entry TLB (translation lookaside buffer)
Write buffer
Thumb code support enabled
90 MHz & 74 MHz clock speeds
MaverickKey™ IDs for DRM
32-bit unique ID
128-bit random ID
Ultra low power
Designed for applications that require long
battery life while using standard AA/AAA
batteries or rechargeable cells
Typical power numbers
— 90 mW at 74 MHz typical
— 108 mW at 90 MHz typical
— <.03 mW in the Standby State
Actual Size
The EP7312-90 is one of the world's fastest ARM-7 embedded
processors today—with clock speeds of up to 90 MHz, it allows for
real-time MP3 encoding, as well as decoding for all major digital
music standards. The EP7312-90 also supports WMA, MP3, and
AAC playback. With faster than real-time MP3 encoding capability,
the need for a personal computer to create digital audio content is
eliminated. Now, manufacturers can easily build portable rotating
media and flash-based audio players that record and store CD/MP3
data during playback—more than ten hours of music content to be
stored on a single CD-RW disc.
The EP7312-90 delivers high performance with low power,
permitting advanced user interfaces and operating systems in
battery powered entertainment devices. A digital audio interface
(DAI) provides a glueless connection to today's most popular DACs
and ADCs, enabling scalable audio performance and price points. It
also includes our patent-pending MaverickKey™ technology, which
provides consumer Internet product manufacturers with on-chip
security utilizing specific hardware IDs, such as those assigned for
DRM or other authentication mechanisms.
Design in the EP7312-90 for a wide range of consumer
entertainment products, including portable and set-top digital audio
devices, car audio jukebox systems, as well as general-purpose
controller applications.
For more information, visit us at
EP7312-90 Features (cont.)
Advanced audio decoder/decompression capability
Allows support of multiple audio decompression
48 Kbytes (0x9600) of on-chip SRAM for fast program
execution and/or as a frame buffer
Two synchronous serial interfaces
Supports MPEG 1, 2, and 2.5 layer 3 audio decoding,
including ISO compliant MPEG 1 and 2 layer 3
support for all standard sample rates and bit rates
Supports bit streams with adaptive bit rates
Improved DAI (Digital Audio Interface) providing
glueless interface to low-power DACs, ADCs, and
SDRAM controller
Supports two memory banks of up to 256 Mbits in
SDRAM memory interface is programmable from 4
to 32 bits wide
27 general-purpose input/output pins
Three 8-bit and one 3-bit GPIO port
Supports scanning keyboard matrix
Two UARTs (16550 type)
Supports bit rates up to 115.2 Kbits/s
Contains two 16-byte FIFOs for TX and RX
UART1 supports modem counter signals
SIR (up to 115.2 kbps) infrared encoder
LCD controller
Interfaces directly to a single-scan panel
monochrome or color STN LCD
Panel width size is programmable from 32 to 1024
pixels in 16-pixel increments
Video frame buffer size programmable up to 128
ADC (SSI) Interface: Master mode only; SPI and
Microwire1-compatible (128 Kbits/s operation)
IrDA (Infrared Data Association) SIR protocol
DC-to-DC converter interface (PWM)
Provides two 96 kHz clock outputs with
programmable duty ration (from 1-in-16 to 15-in-16)
that can be used to drive a DC to DC converter
Two timer counters
Evaluation kit with schematics, sample code, and
design database
Memory controller
Decodes up to 6 separate memory segments of up
to 256 Mbytes each
Support for up to two ultra-low power CL-PS6700 PC
card controllers
Each segment can be configured as 8, 16, or 32 bits
wide with support for page-mode access
Dedicated LED flasher pin from the RTC
Programmable access time for conventional
Full JTAG boundary scan and Embedded ICE support
Commercial and Industrial temperature range
Supports removable FLASH card interface
Enables connection to removable FLASH card for
addition of expansion FLASH memory modules
Optimized for low power dissipation and fabricated on
a fully static 0.25 micon CMOS process
Available in 208 LQFP, 256 PBGA, & 204 TFBGA
For more information, visit us at
Power Management
The EP7312-90 is designed for ultra-low power operation. Its
core operates at only 2.5 V, while I/O has an operational range
of 2.5 V to 3.3 V. The device has three basic power states:
Operating—This state is the full performance state. All the
clocks and peripheral logic are enabled.
Idle—This state is the same as the Operating State,
except the CPU clock is halted while waiting for an event
such as a key press.
Standby—This state is equivalent to the computer being
switched off (no display) and the main oscillator shut
down. An event such as a key press can wake-up the
MaverickKey™ Unique ID
MaverickKey unique hardware programmed IDs are a solution
the growing concern over secure web content and commerce.
With Internet security playing an important role in the delivery
of digital media such as books or music, traditional software
methods are quickly becoming unreliable. The MaverickKey
unique IDs provide OEMs with a method of utilizing specific
hardware IDs such as those assigned for DRM (Digital Right
Management) or any other authentication mechanism.
Both a specific 32-bit ID as well as a 128-bit random ID is
programmed into the EP7312-90 through the use of laser
probing technology. These IDs can then be used to match
secure copyrighted content with the ID of the target device the
EP7312-90 is powering, and then deliver the copyrighted
information over a secure connection. In addition, secure
transactions can benefit by also matching device IDs to server
IDs. MaverickKey IDs provide a level of hardware security
required for today’s Internet appliances.
Memory Interfaces
There are two main external memory interfaces. The first is the
ROM/SRAM/FLASH-style interface that has programmable
wait-state timings and includes burst-mode capability, with
eight chip selects decoding six 256 Mbyte sections of
addressable space. For maximum flexibility, each bank can be
specified to be 8, 16, or 32-bits wide. This allows the use of 8bit wide boot ROM options to minimize system memory
requirements and cost, the ARM Thumb instruction set is
supported providing for the use of high-speed 32-nbit
operations in 16-bit op-codes and yielding industry-leading
code density.
The second is the programmable 4 or 32-bit-wide SDRAM
interface that allows direct connection of up to two banks of
SDRAM, each bank containing up to 256 Mbits. To assure the
lowest possible power consumption, the EP7312 supports
self-refresh DRAMs, which are placed in a low-power Standby
A DMA address generator is also provided that fetches video
display data for the LCD controller from main SDRAM
memory. The display frame buffer start address is
programmable. In addition, the built-in LCD controller can
utilize external or internal SRAM for memory, thus eliminating
the need for SDRAMs.
Digital Audio Capability
The EP7312-90 includes its powerful 32-bit RISC processing
engine to implement audio decompression algorithms in
software. The nature of the on-board RISC processor and the
availability of efficient C-compilers and other software
development tools ensures that a wide range of audio
decompression algorithms can easily be ported to and run on
the EP7312-90.
Serial Interfaces
The EP7312-90 includes two 16550-type UARTs for RS-232
serial communications, both of which have two 16-byte FIFOs
for receiving and transmitting data. The UARTs support bit
rates up to 115.2 kbits/s. An IrDA SIR protocol
encoder/decoder can be optionally switched into the RX/TX
signals to drive an infrared communication interface directly.
Improved Digital Audio Interface (DAI)
The EP7312-90 integrates an interface to enable a direct
connection to many low cost, low power, high quality audio
converters. In particular, the DAI can directly interface with the
Cirrus CS43L41/42/43 low-power audio DACs and CS55L32
low-power ADC. Among the features for these devices are:
digital bass and treble boost, digital volume control, and
compressor-limiter functions.
The EP7312-90 is available in a 208-pin LQFP package and a
256-ball PBGA package.
System Design
As shown in the system block diagram (page 4), simply adding
desired memory and peripherals to the highly integrated
EP7312-90 completes a low-power system solution. All
necessary interface logic is integrated on-chip.
For more information, visit us at
Cirrus Logic, Inc.
Corporate Headquarters
2901 Via Fortuna
Austin, Texas 78746
T: (800) 888-5016
T: (512) 851-4000
F: (512) 851-4977
United States
Cirrus Logic, Inc.
Cirrus Logic K.K.
Cirrus Logic Intl. Ltd.
Cirrus Logic UK
2901 Via Fortuna
Austin, Texas 78746
T: (800) 888-5016
T: (512) 851-4000
F: (512) 851-4977
Cirrus Logic KK
Aioi Sonpo, Bldg. 6F
5-6 Niban-cho, Chiyoda-ku
Tokyo, Japan 102-0084
T 81-3-5226-7390
F 81-3-5226-7677
20F., Ocean Building
80 Shanghai Street
Kowloon, Hong Kong, China
T 852-2376-0801
T 852-2314-9920
F 852-2375-1202
Girdler House
Quebec Road
Oxfordshire RG9 1EY
United Kingdom
T: 44-1491-414-030
F: 44-1491-410-976
Please access our website,, for your nearest local distributor.
© 2002, Cirrus Logic, Inc. All rights reserved. Cirrus, Cirrus Logic, MaverickKey, and Leading the Digital Entertainment Revolution are trademarks of Cirrus Logic, Inc. Other brand
and product names may be trademarks or service marks of their respective owners.
For more information, visit us at