AS3525 Microcontroller IC

Description

The AS3525 is an ultra low-power microcontroller based on the ARM9 32-bit processor with fully integrated high performance audio features and system power management features.

Using advanced 0.13µm process technology and a large on chip RAM leads to outstanding low power consumption of as low as 58mW for a complete flash-player during a typical audio SW playback.

AS3525 is based on the ARM922 processor, with 16kB cache memories and embedded 320K Byte SRAM with performance from 20 ~ 266MHz. The AS3525 features dedicated high speed interfaces for USB2.0 HS-OTG (AS3525A+B), ATA IDE and SDRAM (AS3525A only) ensuring maximum performance for download, upload, and playback.

Furthermore interfaces for NAND flashes, MMC/SD cards and Memory Stick ensure most flexible system design possibilities. Hardware support for parallel interfaces lower the CPU load serving complex and/or color user interfaces.

Additional serial high-speed data and control interfaces guarantee the connection to other peripherals and or processors in the system.

Two independently programmable PLLs generate the required frequencies for audio playback/recording, for the processor core and for the USB interface at the same time. An additional external clock input eliminates the use of external crystals when used in multi-processor systems.

It has a variety of audio inputs and outputs to directly connect microphones, and auxiliary signal sources via a 10-channel mixer to a 16Ω / 32Ω headset, 4Ω speaker or auxiliary audio peripherals.

Further the device offers advanced power management functions. All necessary ICs and peripherals for an audio necessary system with flash or hard-disk memory are supplied by the AS3525. The different regulated supply voltages are fully programmable. The power management block generates 10 different supply voltages out of a single battery supply. CPU, NAND flash, SRAM, memory cards, LCD, LCD backlight and USB-OTG can be powered. When operating from a single cell (AA or AAA) battery, the AS3525 can use a DCDC booster to generate the needed system supply.

The AS3525 has an independent 32kHz real time clock (RTC) on chip, which allows a complete power down of the system CPU and peripherals. AS3525 also contains a charger for Li-Ion battery supply. The single supply voltage may vary from 1.0V to 5.5V.

AS3525 is available in the following two variants:

• 13x13mm, 224 pins in a CTBGA package (AS3525A)
• 10x10mm, 144 pins in a CTBGA package (AS3525B)
  • No IDE Host Interface
  • No External Memory Interface

Both packages are RoHS-compliant.

Key Features

1. Digital Core

• Embedded 32-Bit RISC Controller
  • ARM922TDMI RISC CPU
  • 2.5Mbit on-chip RAM
  • 1Mbit on chip ROM
  • Clock speed max 250MHz (200MIPS)
  • Standard JTAG interface
• USB 2.0 HS & OTG Interface
  • Up to 480Mbit/s transfer speed
  • USB 2.0 HS/FS physical inlcuding OTG support
  • USB 2.0 HS/FS digital core including OTG host
  • Dedicated dual port buffer RAM
  • DMA bus master functionality
• IDE Host Controller (AS3525A)
  • Supporting Ultra ATA 33/66/100/133 modes
  • Programmable IO and Multi-word DMA capability
  • Dedicated dual port buffer RAM
  • DMA bus master functionality
• External Memory Controller (AS3525A)
  • Dynamic memory interface
  • Asynchronous static memory
  • DMA bus master functionality
• DMA Controller
  • Single Master DMA controller
  • 2 DMA channels possible at the same time
  • 16 DMA requests supported
• Interrupt Controller
  • Support for 32 standard interrupts
  • Support for 16 vectored IRQ interrupts
• Audio Subsystem Interface
  • Dedicated 2 wire serial control master
  • I²S input and output with dual port buffer RAM
• Nand Flash Interface
  • 8 and 16bit flash support
  • 3, 4 & 5 byte address support
  • Hardware ECC
• MMC/SD Interface
  • MMC/SD Card host for multiple card support
  • 4 data line support for SD cards
• MS / MS Pro Interface
  • Dedicated dual port buffer RAM
• Display Interface
  • Serial and parallel controller supported
  • On-chip hardware acceleration
• Synchronous Serial Interface
  • Master and slave operation
  • 8/16 bit support
  • Several protocol standards supported
• I²S Interface
  • Input multiplexed with audio subsystem
  • Selectable SPDIF input conversion
  • Dedicated dual port buffer RAM
• 2-Wire Serial Control Interface
  • Master and slave operation
  • Standard and fast mode support
• General Purpose IO Interface
  • 4x 8-bit ports

2. Audio

• Multi-bit Sigma Delta Converters
  • DAC: 18bit with 94dB SNR (‘A’ weighted)
  • ADC: 14bit with 82dB SNR (‘A’ weighted)
  • Sampling Frequency: 8-48kHz
  • 32 gain steps @ 1.5dB and MUTE
• 2 Line Inputs
  • Stereo, 2x mono or mono differential inputs
  • 32 gain steps @ 1.5dB and MUTE
• 2 Microphone Inputs
  • Differential inputs
  • 3 gain pre-sets (28/34/40 dB) and OFF with AGC
  • 32 gain steps @ 1.5dB and MUTE
  • Microphone detection with about 50μA
  • Supply for electret microphone max 1mA
  • Remote control by switch
• Line Output
  • Max 1Vp @ 10kΩ in single ended stereo mode
  • >32Ω in mono differential mode to drive earpieces
  • 32 gain steps @ 1.5dB and MUTE
• Stereo Headphone Audio Amplifier
  • 2x 60mW @ 16Ω driver capacity
  • 32 gain steps @ 1.5dB and MUTE
  • Click- and pop-less start-up and power down
  • Headphone and over-current detection
  • Phantom ground eliminates large capacitors
• Stereo Speaker Audio Amplifier
  • 2x 500mW @ 4Ω driver capacity
  • 32 gain steps @ 1.5dB and MUTE
  • Click- and pop-less start-up and power down
  • Over-current detection
• 10 Channel Audio Mixer
  • Mixes Line inputs, Mic inputs and DAC output
  • Separate selectable source for right and left channel
  • Possibility to select AGC to prevent clipping

3. Power Management

• Voltage Generation
  • Step up for system supply (3.0V-3.6V, 150mA)
  • Charge-pump for CPUcore (1.05V-1.2V, 50mA)
  • Charge pump for USB OTG (5V, 10mA)
  • LDO for digital supply (2.9V, 200mA)
  • LDO for analog supply (2.9V, 200mA)
  • LDO for IO supply (2.94 or 3.11V, 200mA)
  • LDO for peripherals (1.7V-3.3V, 200mA)
  • LDO for USB Transceiver (3.26V, 200mA)
  • LDO for RTC (1.0V-2.5V, 2mA)
• 25V Back-light step-up converter
  • For driving up to 6 white LEDs in series to achieve a uniform illumination
  • Current programmable up to 40mA (1.25mA steps)
• Li-Io Battery Charger
  • Automatic 50mA trickle charging
  • Prog. constant current charging (50-400mA)
  • Prog. constant voltage charging (3.9-4.25V)

4. System

• RTC
  • Ultra low power 32kHz oscillator
  • 32bit RTC second counter
  • Selectable alarm (seconds or minutes)
  • Trim able oscillator
• Oscillator
  • Low power 12-24MHz Oscillator
  • Generating main system clock
• Supervisor
  • Automatic battery monitoring with interrupt generation and selectable warning level
  • Automatic temperature supervision with interrupt generation and selectable warning and shutdown levels
• General Purpose ADC
  • 10-bit resolution
  • 16 inputs analog multiplexer
• UID
  • Unique Identification Number in OTP ROM for DRM support
• General
  • Reset pin, watchdog
  • 10sec emergency shut-down
  • Wide battery supply range 1V-5.5V
  • MP3 playback with 58mW
• Packages:
  • AS3525A: CTBGA224 13x13mm, 0.8mm pitch
  • AS3525B: CTBGA144 10x10mm, 0.8mm pitch

Applications

• Portable Voice Recorders
• Portable Music Recorders
• Wearables
• Personal Museum Guides
• Audiobooks
• Remote Controls
• e-books
• Broadband Internet Gadgets
• Point-of-sales(POS) equipment
• USB Transport Controller
• USB to GPRS Adapter

Block Diagram