ADI公司的ADuCM360/1是集成了32位ARM CORTEX M3处理器和双通道24位sigma-delta(Σ-Δ)型ADC以及闪存/EE存储器的低功耗精密模拟微控制器,包含了片上32kHz振荡器和16MHz高频振荡器以及大量的外设,主要用在工业自动化和过程控制,智能精密测量系统,4mA-20mA智能检测系统以及医疗设备,病人监护设备.本文介绍了ADuCM360/1主要特性,功能框图,系统配置图以及评估板EVAL-ADICUP360主要特性,电路图和材料清单.
The ADuCM360 is a fully integrated, 3.9 kSPS, 24-bit data acquisition system that incorporates dual high performance, multichannel sigma-delta (Σ-Δ) analog-to-digital converters (ADCs), a 32-bit ARM Cortex™-M3 processor, and Flash/EE memory on a single chip. The ADuCM360 is designed for direct interfacing to external precision sensors in both wired and battery-powered applications. The ADuCM361 contains all the features of the ADuCM360 except that only one 24-bit Σ-Δ ADC (ADC1) is available.
The ADuCM360/ADuCM361 contain an on-chip 32 kHz oscillator and an internal 16 MHz high frequency oscillator. The high frequency oscillator is routed through a programmable clock divider from which the operating frequency of the processor core clock is generated. The maximum core clock speed is 16 MHz; this speed is not limited by operating voltage or temperature.
The microcontroller core is a low power ARM Cortex-M3 processor, a 32-bit RISC machine that offers up to 20 MIPS peak performance. The Cortex-M3 processor incorporates a flexible, 11-channel DMA controller that supports all wired communica-tion peripherals (SPI, UART, and I2C). Also integrated on chip are 128 kB of nonvolatile Flash/EE memory and 8 kB of SRAM.
The analog subsystem consists of dual ADCs, each connected to a flexible input mux. Both ADCs can operate in fully differential and single-ended modes. Other on-chip ADC features include dual programmable excitation current sources, diagnostic current sources, and a bias voltage generator of AVDD_REG/2 (900 mV) to set the common-mode voltage of an input channel. A low-side internal ground switch is provided to allow power-down of an external circuit (for example, a bridge circuit) between conversions.
The ADCs contain two parallel filters: a sinc3 or sinc4 filter in parallel with a sinc2 filter. The sinc3 or sinc4 filter is used for precision measurements. The sinc2 filter is used for fast measure-ments and for the detection of step changes in the input signal.
The devices contain a low noise, low drift internal band gap reference, but they can be configured to accept one or two external reference sources in ratiometric measurement configurations. An option to buffer the external reference inputs is provided on chip. A single-channel buffered voltage output DAC is also provided on chip.
The ADuCM360/ADuCM361 integrates a range of on-chip peripherals, which can be configured under microcontroller software control as required in the application. The peripherals include UART, I2C, and dual SPI serial I/O communication controllers; a 19-pin GPIO port; two general-purpose timers; a wake-up timer; and a system watchdog timer. A 16-bit PWM controller with six output channels is also provided.
The ADuCM360/ADuCM361 are specifically designed to operate in battery-powered applications where low power operation is critical. The microcontroller core can be configured in a normal operating mode that consumes 290 μA/MHz (including flash/ SRAM IDD). An overall system current consumption of 1 mA can be achieved with both ADCs on (input buffers off), PGA gain of 4, one SPI port on, and all timers on.
The ADuCM360/ADuCM361 can be configured in a number of low power operating modes under direct program control, including a hibernate mode (internal wake-up timer active) that consumes only 4 μA. In hibernate mode, peripherals such as external interrupts or the internal wake-up timer can wake up the device. This mode allows the part to operate with ultralow power and still respond to asynchronous external or periodic events.
On-chip factory firmware supports in-circuit serial download via a serial wire interface (2-pin JTAG system) and UART; non-intrusive emulation is also supported via the serial wire interface. These features are incorporated into a low cost QuickStart™ Development System that supports this precision analog micro-controller family.
The parts operate from an external 1.8 V to 3.6 V voltage supply and are specified over an industrial temperature range of −40℃ to +125℃.
Dual 24-bit ADCs (ADuCM360)
Single 24-bit ADC (ADuCM361)
Programmable ADC output rate (3.5 Hz to 3.906 kHz)
Simultaneous 50 Hz/60 Hz noise rejection
At 50 SPS continuous conversion mode
At 16.67 SPS single conversion mode
Flexible input mux for input channel selection to both ADCs
Two 24-bit multichannel ADCs (ADC0 and ADC1)
6 differential or 11 single-ended input channels
4 internal channels for monitoring DAC, temperature sensor, IOVDD/4, and AVDD/4 (ADC1 only)
Programmable gain (1 to 128)
RMS noise: 52 nV at 3.53 Hz, 200 nV at 50 Hz
Programmable sensor excitation current sources
On-chip precision voltage reference
Single 12-bit voltage output DAC
NPN mode for 4 mA to 20 mA loop applications
ARM Cortex-M3 32-bit processor
Serial wire download and debug
Internal watch crystal for wake-up timer
16 MHz oscillator with 8-way programmable divider
128 kB Flash/EE memory, 8 kB SRAM
In-circuit debug/download via serial wire and UART
Power supply range: 1.8 V to 3.6 V (maximum)
Power consumption, MCU active mode
Core consumes 290 μA/MHz
Overall system current consumption of 1.0 mA with core operating at 500 kHz (both ADCs on, input buffers off, PGA gain of 4, one SPI port on, and all timers on)
Power consumption, power-down mode: 4 μA (wake-up timer active)
UART, I2C, and 2 × SPI serial I/O
16-bit PWM controller
19-pin multifunction GPIO port
2 general-purpose timers
Wake-up timer/watchdog timer
Multichannel DMA and interrupt controller
Package and temperature range
48-lead, 7 mm×7 mm LFCSP
Specified for −40℃ to +125℃ operation
Low cost QuickStart Development System
Third-party compiler and emulator tool support
Multiple functional safety features for improved diagnostics
Industrial automation and process control
Intelligent precision sensing systems
4 mA to 20 mA loop-powered smart sensor systems
Medical devices, patient monitoring
The EVAL-ADICUP360base board consists of two basic blocks:
A fully integrated, 3.9 kSPS, 24-bit data acquisition system that incorporates dual high performance, multichannel sigma-delta (Σ-Δ) analog-to-digital converters (ADCs), a 32-bit ARM Cortex™-M3 processor, and Flash/EE memory, realized on a single chip ADuCM360 microcontroller.
An on-board SWD interface, based on the OpenSDA platform, which is implemented with the Freescale’s К20DX128 microcontroller. This block allows using a free Software Development Toolchain to program and debug the ADuCM360 microcontroller part.
This page describes the hardware connectors, the jumpers and switches configuration options, the USB connectors, and links to download the schematics and the layout.