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AN-1111
APPLICATION NOTE
One Technology Way • P. O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Tel: 781.329.4700 • Fax: 781.461.3113 • www.analog.com
Options for Minimizing Power Consumption When Using the ADuCM360/ADuCM361
By Mike Looney
Rev. 0 | Page 1 of 12
INTRODUCTION
The ADuCM360 is a 32-bit ARM® Cortex™-M3-based
microcontroller that integrates dual 24-bit sigma delta (Σ-Δ)
analog-to-digital converters (ADCs), each with a fully pro-
grammable instrumentation amplifier on the front end. The
ADuCM361 contains all of the features of the ADuCM360
except that it has a single 24-bit sigma delta ADC (ADC1).
This application note describes many of the operational modes
and clock options for these devices and details the power savings
for each configuration.
These microcontrollers target a wide range of applications
including industrial control and instrumentation applications.
In many of the target applications, reducing power consumption
in the application is of the utmost importance. For example, for
battery-powered applications, the lifetime of the battery can be
extended by using the many operating modes and clock options
on the ADuCM360/ADuCM361. In addition, in 4 mA to 20 mA
loop-based applications where ADC performance is important,
the ADuCM360/ADuCM361 ensure that the overall power
consumption of the sensor module remains below 3.2 mA.
For details regarding the specifications and operation of the
ADuCM360/ADuCM361, refer to the latest datasheet and the
UG-367 user guide.
By maximizing the use of clock and power mode options,
the average I
DD
consumed by the ADuCM360/ADuCM361
can be reduced to just 1 mA. This figure is achieved despite
both the ADCs and the PGAs on the front end being enabled,
the ARM Cortex-M3 processor being set to active mode, and
the SPI buses and all timers being enabled.
All I
DD
measurements in this document are typical values
measured at ambient temperature (25°C) using a supply voltage
of AV
DD
= IOVDD = 3.0 V.