CN0221 Datasheet, PDF (1/5 Pages) Analog Devices – Devices Connected

Circuit Note
CN-0221
Circuits from the Lab® reference designs are engineered and
tested for quick and easy system integration to help solve today’s
analog, mixed-signal, and RF design challenges. For more
information and/or support, visit www.analog.com/CN0221.
Devices Connected/Referenced
ADuCM360/ Cortex-M3 Based Microcontroller with
ADuCM361 Dual 24-Bit Σ-Δ ADCs
ADP1720-3.3 Low Dropout Linear Regulator
USB-Based, Thermocouple Temperature Measurement System Using ARM Cortex-M3
EVALUATION AND DESIGN SUPPORT
Circuit Evaluation Board
CN-0221 Evaluation Board (EVAL-ADuCM360TCZ)
Design and Integration Files
Schematics, Layout Files, Bill of Materials, source code for
ADuCM360
converter (DAC), and a 1.2 V internal reference, as well as an ARM
Cortex-M3 core, 128 kB flash, 8 kB SRAM, and various digital
peripherals such as UART, timers, SPIs, and I²C interfaces.
In the circuit, the ADuCM360/ADuCM361 is connected to a
thermocouple and a 100 Ω platinum resistance temperature
detector (RTD). The RTD is used for cold junction compensation.
CIRCUIT FUNCTION AND BENEFITS
In the source code, an ADC sampling rate of 4 Hz is chosen. When
This circuit uses the ADuCM360/ADuCM361 precision analog
microcontroller in an accurate thermocouple temperature
monitoring application. The ADuCM360/ADuCM361 integrates
the ADC input programmable gain amplifier (PGA) is configured
for a gain of 32, the noise-free code resolution of the ADuCM360/
ADuCM361 is greater than 18 bits.
dual 24-bit sigma-delta (Σ-Δ) analog-to-digital converters (ADCs),
dual programmable current sources, a 12-bit digital-to-analog
USB HEADER
BEAD
5V
3.3V
ADP1720-3.3
IN
OUT
BEAD _10Ω
10µF
GND
4.7µF
4.7µF
0.1µF
0.1µF
D–
D+
GND
SHIELD
0.1µF
BEAD
FT232R
TxD
RxD
AVDD
AIN5/IEXC
100Ω
PtRTD
10Ω
0.01µF
AIN0
IOVDD
RESET
P2.2/BM
RESET
SD
10Ω
AIN1
FERRITE BEADS:
1kΩ @ 100MHz
TAIYO YUDEN
BK2125HS102-T
0.01µF
R_REF
5.6kΩ
0.1%
V_REF+
V_REF–
ADuCM360
AIN2
THERMOCOUPLE
JUNCTION
J1
AIN3
AIN7/VBIAS
AGND
TxD
RxD
Figure 1. ADuCM360/ADuCM361 as a Temperature Monitor Controller with a Thermocouple Interface (Simplified Schematic, All Connections Not Shown)
Rev. C
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