Datasheet ADUCM355 (Analog Devices) - 4

ADuCM355 Data Sheet GENERAL DESCRIPTION
The ADuCM355 is an on-chip system that controls and measures machine. The Arm Cortex-M3 processor also has a flexible electrochemical sensors and biosensors. The ADuCM355 is an multichannel direct memory access controller (DMA) ultralow power, mixed-signal microcontroller based on the supporting two independent serial peripheral interface (SPI) ports, Arm® Cortex™-M3 processor. The device features current, universal asynchronous receiver/transmitter (UART), and I2C voltage, and impedance measurement capability. communication peripherals. The ADuCM355 has 128 kB of The ADuCM355 features a 16-bit, 400 kSPS, multichannel nonvolatile flash/EE memory and 64 kB of single random successive approximation register (SAR) analog-to-digital access memory (SRAM) integrated on-chip. converter (ADC) with input buffers, built-in antialias filter The digital processor subsystem is clocked from a 26 MHz (AAF), and programmable gain amplifier (PGA). The current on-chip oscillator. The oscillator is the source of the main inputs include three transimpedance amplifiers (TIA) with digital die system clock. Optionally, a 26 MHz phase-locked programmable gain and load resistors for measuring different loop (PLL) can be used as the digital system clock. This clock sensor types. The analog front end (AFE) also contains two low can be internally subdivided so that the processor operates at a power amplifiers designed specifically for potentiostat capability lower frequency and saves power. A low power, internal 32 kHz to maintain a constant bias voltage to an external electrochemical oscillator is available and can clock the timers. The ADuCM355 sensor. The noninverting inputs of these two amplifiers are includes three general-purpose timers, a wake-up timer (which controlled by on-chip, dual output digital-to-analog converters can be used as a general-purpose timer), and a system (DACs). The analog outputs include a high speed DAC and watchdog timer. output amplifier designed to generate an ac signal. The analog subsystem has a separate 16 MHz oscillator used to The ADC operates at conversion rates up to 400 kSPS with an clock the ADC, DACs, and other digital logic on the analog die. input range of −0.9 V to +0.9 V. An input mux before the ADC The analog die also contains a separate 32 kHz, low power allows the user to select an input channel for measurement. oscillator to clock a watchdog timer on the analog die. Both the These input channels include three external current inputs, 32 kHz oscillator and this watchdog are independent from the multiple external voltage inputs, and internal channels. The digital die oscillators and system watchdog timer. internal channels allow diagnostic measurements of the A range of communication peripherals can be configured as internal supply voltages, die temperature, and reference required in a specific application. These peripherals include voltages. UART, I2C, two SPI ports, and general-purpose input/output Two of the three voltage DACs are dual output, 12-bit string (GPIO) ports. The GPIOs, combined with the general-purpose DACs. One output per DAC controls the noninverting input of timers, can be combined to generate a pulse-width modulation a potentiostat amplifier, and the other controls the (PWM) type output. noninverting input of the TIA. Nonintrusive emulation and program download are supported The third DAC (sometimes referred to as the high speed DAC) via the serial wire debug port (SW-DP) interface. is designed for the high power TIA for impedance The ADuCM355 operates from a 2.8 V to 3.6 V supply and is measurements. The output frequency range of this DAC is up to specified over a temperature range of −40°C to +85°C. The chip 200 kHz. is packaged in a 72-lead, 6 mm × 5 mm land grid array (LGA) A precision 1.82 V and 2.5 V on-chip reference source is available. package. The internal ADC and voltage DAC circuits use this on-chip Note that, throughout this data sheet, multifunction pins, such reference source to ensure low drift performance for all as P0.0/SPI0_CLK, are referred to either by the entire pin name peripherals. or by a single function of the pin, for example, P0.0, when only The ADuCM355 integrates a 26 MHz Arm Cortex-M3 processor, that function is relevant. which is a 32-bit reduced instruction set computer (RISC) Rev. C | Page 4 of 28 Document Outline FEATURES APPLICATIONS SIMPLIFIED FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY FUNCTIONAL BLOCK DIAGRAM GENERAL DESCRIPTION SPECIFICATIONS MICROCONTROLLER ELECTRICAL SPECIFICATIONS RMS NOISE RESOLUTION OF ADC TIMING SPECIFICATIONS Timing Diagrams ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS APPLICATIONS INFORMATION RECOMMENDED CIRCUIT AND COMPONENT VALUES OUTLINE DIMENSIONS ORDERING GUIDE