Targets: Audio, Communication & Wired, Consumer

austriamicrosystems AS3525 Block Diagram

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. It features 16-kbyte cache memories and embedded 320-kbyte SRAM with performance from 20 to 266 MHz operation. The AS3525 includes dedicated high-speed interfaces for USB2.0 HS-OTG (AS3525A+B), ATA IDE, and SDRAM (AS3525A only). Memory interfaces support NAND flashes, MMC/SD cards, and Memory Stick.

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. The AS3525 has an independent 32 kHz RTC (real time clock) on chip, which allows a complete power down of the system CPU and peripherals.

The AS3525 includes 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.

The device offers advanced power management functions. The different regulated supply voltages are fully programmable. The power management block generates 10 different supply voltages out of a single battery supply to power the CPU, NAND flash, SRAM, memory cards, LCD, LCD backlight and USB-OTG. When operating from a single cell (AA or AAA) battery, the AS3525 can use a DCDC booster to generate the needed system supply. 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 a 13x13 mm, 224 pins in a CTBGA package (AS3525A) and a 10x10 mm, 144 pins in a CTBGA package (AS3525B). Both packages are RoHS-compliant.