ADUC816 Analog Devices, ADUC816 Datasheet - Page 32

• Manufacturer Part Number: ADUC816
• Description: Precision Analog Microcontroller: 1MIPS 8052 MCU + 8kB Flash + Dual 16-Bit ADC + 12-Bit DAC
• Manufacturer: Analog Devices

Specifications of ADUC816

• Mcu Core: 8052
• Mcu Speed (mips): 1.3
• Sram (bytes): 256Bytes
• Gpio Pins: 34
• Adc # Channels: 4

Auxiliary ADC
The Auxiliary ADC is intended to convert supplementary inputs
such as those from a cold junction diode or thermistor. This ADC
is not buffered and has a fixed input range of 0 V to 2.5 V
TEMPERATURE
ON-CHIP
SENSOR
THE MULTIPLEXER IS CONTROLLED VIA
CONVERSION CYCLE. CHOPPING
AIN3
AIN4
AIN5
EXTERNAL SINGLE ENDED INPUTS OR
THE INPUTS ARE ALTERNATELY
ANALOG INPUT CHOPPING
OFFSET AND OFFSET DRIFT
REVERSED THROUGH THE
ALLOWS SELECTION OF THREE
A DIFFERENTIAL MULTIPLEXER
YIELDS EXCELLENT ADC
THE ON-CHIP TEMP. SENSOR.
ANALOG MULTIPLEXER
THE CHANNEL SELECTION
SEE PAGE 28 AND 33
PERFORMANCE
SEE PAGE 36
BITS IN ADC1CON
MUX
MU
X
CHOP
REFIN(–)
THE EXTERNAL REFERENCE INPUT TO
ENCE VOLTAGE IS SELECTED VIA THE
DETECT CIRCUITRY TESTS FOR OPEN
XREF1 BIT IN ADC1CON. REFERENCE
OPERATION. THE EXTERNAL REFER-
THE ADuC816 IS DIFFERENTIAL AND
OR SHORTED REFERENcES INPUTS
DIFFERENTIAL REFERENCE
FACILITATES RATIOMETRIC
STREAM (THE OUTPUT OF WHICH
REFIN(+)
THE MODULATOR PROVIDES A
HIGH FREQUENCY 1-BIT DATA
REPRESENTS THE SAMPLED
THE DUTY CYCLE OF WHICH
IS ALSO CHOPPED) TO THE
SEE PAGE 35
ANALOG INPUT VOLTAGE
SIGMA-DELTA
DIGITAL FILTER,
MODULATOR
MODULATOR
SEE PAGE 35
SIGMA-DELTA A/D CONVERTER
SIGMA-
DELTA
PROGRAMMABLE
DIGITAL FILTER
(assuming an external 2.5 V reference). The single-ended inputs
can be driven from AIN3, AIN4 or AIN5 pins or directly from
the on-chip temperature sensor voltage. A block diagram of the
Auxiliary ADC is shown in Figure 19.
CHOPPED TO REMOVE DRIFT
ARCHITECTURE ENSURES
SIGMA-DELTA ADC
SIGMA-DELTA ADC IS
16 BITS NO MISSING
CODES. THE ENTIRE
THE SIGMA-DELTA
SEE PAGE 35
QUANTIZATION NOISE INTRODUCED
BY THE MODULATOR. THE UPDATE
PROGRAMMABLE DIGITAL
RATE AND BANDWIDTH OF THIS
FILTER ARE PROGRAMMABLE
ERRORS
THE SINC 3 FILTER REMOVES
VIA THE SF SFR
SEE PAGE 35
CHOP
FILTER
AVERAGE
OUTPUT
AS PART OF THE CHOPPING
WITH ITS PREDECESSOR
SUMMED AND AVERAGED
IMPLEMENTATION EACH
TO NULL ADC CHANNEL
OUTPUT AVERAGE
DATA WORD OUTPUT
FROM THE FILTER IS
OFFSET ERRORS
SEE PAGE 36
DIGITAL FILTER IS SCALED BY
THE OUPUT WORD FROM THE
THE CONVERSION RESULT
SCALING
OUTPUT
COEFFICIENTS BEFORE
OUTPUT SCALING
BEING PROVIDED AS
THE CALIBRATION
SEE PAGE 37
RESULT WRITTEN
TO ADC1H/L SFRs
DIGTAL OUTPUT
REV. A