ADUC816 Datasheet, PDF (1/68 Pages) Analog Devices – MicroConverter-R, Dual-Channel 16-Bit ADCs with Embedded Flash MCU

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MicroConverter^®, Dual-Channel
16-Bit ADCs with Embedded Flash MCU
ADuC816
FEATURES
High-Resolution Sigma-Delta ADCs
Dual 16-Bit Independent ADCs
Programmable Gain Front End
16-Bit No Missing Codes, Primary ADC
13-Bit p-p Resolution @ 20 Hz, 20 mV Range
16-Bit p-p Resolution @ 20 Hz, 2.56 V Range
Memory
8 Kbytes On-Chip Flash/EE Program Memory
640 Bytes On-Chip Flash/EE Data Memory
Flash/EE, 100 Year Retention, 100 Kcycles Endurance
256 Bytes On-Chip Data RAM
8051-Based Core
8051-Compatible Instruction Set (12.58 MHz Max)
32 kHz External Crystal, On-Chip Programmable PLL
Three 16-Bit Timer/Counters
26 Programmable I/O Lines
11 Interrupt Sources, Two Priority Levels
Power
Specified for 3 V and 5 V Operation
Normal: 3 mA @ 3 V (Core CLK = 1.5 MHz)
Power-Down: 20 ␮A (32 kHz Crystal Running)
On-Chip Peripherals
On-Chip Temperature Sensor
12-Bit Voltage Output DAC
Dual Excitation Current Sources
Reference Detect Circuit
Time Interval Counter (TIC)
UART Serial I/O
I²C^®-Compatible and SPI^® Serial I/O
Watchdog Timer (WDT), Power Supply Monitor (PSM)
APPLICATIONS
Intelligent Sensors (IEEE1451.2-Compatible)
Weigh Scales
Portable Instrumentation
Pressure Transducers
4–20 mA Transmitters
GENERAL DESCRIPTION
The ADuC816 is a complete smart transducer front-end, inte-
grating two high-resolution sigma-delta ADCs, an 8-bit MCU,
and program/data Flash/EE Memory on a single chip. This low
power device accepts low-level signals directly from a transducer.
The two independent ADCs (Primary and Auxiliary) include a
temperature sensor and a PGA (allowing direct measurement of
low-level signals). The ADCs with on-chip digital filtering are
MicroConverter is a registered trademark of Analog Devices, Inc.
SPI is a registered trademark of Motorola, Inc.
I²C is a registered trademark of Philips Semiconductors, Inc.
REV. 0
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
FUNCTIONAL BLOCK DIAGRAM
AIN1
AIN2
AIN3
AIN4
AIN5
AVDD
ADuC816
AVDD
MUX
BUF
PGA
MUX
AGND
AUXILIARY
16-BIT ⌺-⌬ ADC
PRIMARY
16-BIT ⌺-⌬ ADC
12-BIT
VOLTAGE O/P
DAC
CURRENT
SOURCE
MUX
BUF
TEMP
SENSOR
INTERNAL
BANDGAP
VREF
PROG.
CLOCK
DIVIDER
EXTERNAL
VREF
DETECT
OSC
&
PLL
8051-BASED MCU WITH ADDITIONAL
PERIPHERALS
8 KBYTES FLASH/EE PROGRAM MEMORY
640 BYTES FLASH/EE DATA MEMORY
256 BYTES USER RAM
3 ؋ 16 BIT
TIMER/COUNTERS
1 ؋ TIME INTERVAL
COUNTER
ON-CHIP MONITORS
POWER SUPPLY
MONITOR
WATCHDOG TIMER
4 ؋ PARALLEL
PORTS
I²C-COMPATIBLE
UART AND SPI
SERIAL I/O
REFIN– REFIN+ XTAL1 XTAL2
IEXC1
IEXC2
DAC
intended for the measurement of wide dynamic range, low
frequency signals, such as those in weigh scale, strain gauge,
pressure transducer, or temperature measurement applications.
The ADC output data rates are programmable and the ADC
output resolution will vary with the programmed gain and
output rate.
The device operates from a 32 kHz crystal with an on-chip PLL
generating a high-frequency clock of 12.58 MHz. This clock is,
in turn, routed through a programmable clock divider from which
the MCU core clock operating frequency is generated. The
microcontroller core is an 8052 and therefore 8051-instruction-
set-compatible. The microcontroller core machine cycle consists
of 12 core clock periods of the selected core operating frequency.
8 Kbytes of nonvolatile Flash/EE program memory are provided
on-chip. 640 bytes of nonvolatile Flash/EE data memory and
256 bytes RAM are also integrated on-chip.
The ADuC816 also incorporates additional analog functionality
with a 12-bit DAC, current sources, power supply monitor,
and a bandgap reference. On-chip digital peripherals include a
watchdog timer, time interval counter, three timers/counters,
and three serial I/O ports (SPI, UART, and I²C-compatible).
On-chip factory firmware supports in-circuit serial download and
debug modes (via UART), as well as single-pin emulation mode
via the EA pin. A functional block diagram of the ADuC816 is
shown above with a more detailed block diagram shown in
Figure 12.
The part operates from a single 3 V or 5 V supply. When operating
from 3 V supplies, the power dissipation for the part is below
10 mW. The ADuC816 is housed in a 52-lead MQFP package.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
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© Analog Devices, Inc., 2001