MicroConverter
®
Multichannel
24-/16-Bit ADCs with Embedded 62 kB
Flash and Single-Cycle MCU

ADuC845/ADuC847/ADuC848


Rev. A
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infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
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Tel: 781.329.4700 www.analog.com
Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved.
FEATURES
High resolution Σ-∆ ADCs
Two independent 24-bit ADCs on the ADuC845
Single 24-bit ADC on the ADuC847 and
single 16-bit ADC on the ADuC848
Up to 10 ADC input channels on all parts
24-bit no missing codes
22-bit rms (19.5 bit p-p) effective resolution
Offset drift 10 nV/°C, gain drift 0.5 ppm/°C chop enabled

Memory
62-kbyte on-chip Flash/EE program memory
4-kbyte on-chip Flash/EE data memory
Flash/EE, 100 year retention, 100 kcycle endurance
3 levels of Flash/EE program memory security
In-circuit serial download (no external hardware)
High speed user download (5 seconds)
2304 bytes on-chip data RAM

8051-based core
8051-compatible instruction set
High performance single-cycle core
32 kHz external crystal
On-chip programmable PLL (12.58 MHz max)
3 × 16-bit timer/counter
24 programmable I/O lines, plus 8 analog or
digital input lines
11 interrupt sources, two priority levels
Dual data pointer, extended 11-bit stack pointer

On-chip peripherals
Internal power-on reset circuit
12-bit voltage output DAC
Dual 16-bit Σ-∆ DACs
On-chip temperature sensor (ADuC845 only)
Dual excitation current sources (200 µA)
Time interval counter (wake-up/RTC timer)
UART, SPI®, and I
2
C® serial I/O
High speed dedicated baud rate generator (incl 115,200)
Watchdog timer (WDT)
Power supply monitor (PSM)
Power
Normal: 4.8 mA max @ 3.6 V (core CLK = 1.57 MHz)
Power-down: 20 µA max with wake-up timer running
Specified for 3 V and 5 V operation
Package and temperature range:
52-lead MQFP (14 mm × 14 mm), −40°C to +125°C
56-lead CSP (8 mm × 8 mm), −40°C to +85°C

APPLICATIONS
Multichannel sensor monitoring
Industrial/environmental instrumentation
Weigh scales, pressure sensors, temperature monitoring
Portable instrumentation, battery-powered systems
Data logging, precision system monitoring

FUNCTIONAL BLOCK DIAGRAM
62 kBYTES FLASH/EE PROGRAM MEMORY
4 kBYTES FLASH/EE DATA MEMORY
2304 BYTES USER RAM
3 × 16 BIT TIMERS
BAUD RATE TIMER
4× PARALLEL
PORTS
SINGLE-CYCLE 8061 BASED MCU
ADuC845
TEMP
SENSOR
CURRENT
SOURCE
AIN0
AIN9
AINCOM
RESET
DV
DD
DGND
WAKE-UP/
RTC TIMER
IEXC1
IEXC2
PWM0
PGABUF
MUX
AUXILIARY
24-BIT Σ-∆ ADC
PRIMARY
24-BIT Σ-∆ ADC
DACBUF
PWM1
12-BIT
DAC
AV
DD
DUAL 16-BIT
Σ-∆ DAC
DUAL 16-BIT
PWM
POWER SUPPLY MON
WATCHDOG TIMER
UART, SPI, AND I
2
C
SERIAL I/O
MUX
04741-
0-
001
XTAL2XTAL1
OSC
AVCO
AGND
PLL AND PRG
CLOCK DIV
POR
REFIN+
REFIN–
REFIN2–
REFIN2+
EXTERNAL
V
REF
DETECT
INTERNAL
BAND GAP
V
REF

Figure 1. ADuC845 Functional Block Diagram