Analog Devices ADuC812 manual General Description, Functional Block Diagram

a	MicroConverter®, Multichannel
	12-Bit ADC with Embedded FLASH MCU
	ADuC812

FEATURES

ANALOG I/O

8-Channel, High Accuracy 12-Bit ADC On-Chip, 100 ppm/ C Voltage Reference High-Speed 200 kSPS

DMA Controller for High-Speed ADC-to-RAM Capture Two 12-Bit Voltage Output DACs

On-Chip Temperature Sensor Function

MEMORY

8K Bytes On-Chip Flash/EE Program Memory

640Bytes On-Chip Flash/EE Data Memory

256Bytes On-Chip Data RAM

16M Bytes External Data Address Space

64K Bytes External Program Address Space

8051-COMPATIBLE CORE

12 MHz Nominal Operation (16 MHz Max) Three 16-Bit Timer/Counters

High Current Drive Capability—Port 3

Nine Interrupt Sources, Two Priority Levels

POWER

Specified for 3 V and 5 V Operation Normal, Idle, and Power-Down Modes

ON-CHIP PERIPHERALS UART Serial I/O

2-Wire (I2C®-Compatible) and SPI® Serial I/O Watchdog Timer

Power Supply Monitor

APPLICATIONS

Intelligent Sensors Calibration and Conditioning

Battery Powered Systems (Portable PCs, Instruments,

Monitors)

Transient Capture Systems

DAS and Communications Systems

Control Loop Monitors (Optical Networks/Base Stations)

GENERAL DESCRIPTION

The ADuC812 is a fully integrated 12-bit data acquisition system incorporating a high performance self calibrating multichannel ADC, dual DAC and programmable 8-bit MCU (8051 instruc- tion set compatible) on a single chip.

The programmable 8051-compatible core is supported by 8K bytes Flash/EE program memory, 640 bytes Flash/EE data memory and 256 bytes data SRAM on-chip.

Additional MCU support functions include Watchdog Timer, Power Supply Monitor and ADC DMA functions. 32 Pro- grammable I/O lines, I2C-compatible, SPI and Standard UART Serial Port I/O are provided for multiprocessor interfaces and I/O expansion.

Normal, idle, and power-down operating modes for both the MCU core and analog converters allow for flexible power man- agement schemes suited to low power applications. The part is specified for 3 V and 5 V operation over the industrial tem- perature range and is available in a 52-lead, plastic quad flatpack package.

FUNCTIONAL BLOCK DIAGRAM

P0.0–P0.7

P1.0–P1.7

P2.0–P2.7

P3.0–P3.7

AIN0 (P1.0)–AIN7 (P1.7)

12-BIT

ADC

DAC0

BUF

DAC0

CONTROL

DAC

AIN

T/H

SUCCESSIVE

AND

MUX

APPROXIMATION

CONTROL

CALIBRATION

ADC

BUF

LOGIC

DAC1

DAC1

T0 (P3.4)

MICROCONTROLLER

T1 (P3.5)

8051 BASED

POWER SUPPLY

3

16-BIT

T2 (P1.0)

2.5V

TEMP

MICROCONTROLLER CORE

MONITOR

TIMER/COUNTERS

T2EX (P1.1)

REF

SENSOR

8K

8 PROGRAM

WATCHDOG

2-WIRE

INT0 (P3.2)

SPI

FLASH EEPROM

TIMER

SERIAL I/O

INT1 (P3.3)

VREF

BUF

640

8 USER

UART

MUX

ALE

FLASH EEPROM

256

8 USER

PSEN

ADuC812

OSC

EA

RAM

CREF

RESET

AVDD

AGND

DVDD

DGND

XTAL1 XTAL2 RxD

TxD

SCLOCK MOSI/

MISO

(P3.0) (P3.1)

SDATA

(P3.3)

MicroConverter is a registered trademark of Analog Devices, Inc.

I2C is a registered trademark of Philips Corporation.

SPI is a registered trademark of Motorola Inc.

REV. B

Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

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Fax: 781/326-8703	© Analog Devices, Inc., 2001