Datasheet

 2012-2013 Microchip Technology Inc. Advance Information DS40001667C-page 17
MGC3130
4.2.3 CLOCKS
The MGC3130 is embedding two internal oscillators,
high speed and low speed. The High-Speed Oscillator
(HSO) is factory-trimmed, achieving high accuracy.
• High-Speed Oscillator (HSO)
:
The MGC3130 is clocked by an internal HSO running
at 22.5 MHz ±10% and consuming very low power. This
clock is used to generate the Tx signal, to trigger the
ADC conversions and to run the SPU. During Deep
Sleep mode, the HSO clock is switched off.
• Low-Speed Oscillator (LSO)
:
This low-speed and ultra-low-power oscillator is
typically 32 kHz with a tolerance of ±10 kHz. It is used
during power-saving modes.
4.2.4 OPERATION MODES
MGC3130 offers three operation modes that allow the
user to balance power consumption with device
functionality. In all of the modes described in this
section, power saving is configured by GestIC Library
messages.
4.2.4.1 Processing Mode
In this mode, all power domains are enabled and the
SPU is running continuously. All peripheral digital
blocks are active. Each Rx channel can be activated
individually by GestIC Library depending on the
application. Gesture Recognition and Position Tracking
require the Processing Operation mode.
4.2.4.2 Deep Sleep Mode
During the Deep Sleep mode, VDDM and VDDA are
turned off, and V
DDC is still powered to retain the data
of the SPU.
The mode includes the following characteristics:
• The SPU is halted
• The High-Speed Oscillator is shut down
• The Low-Speed Oscillator is running
• The Watchdog is switched off
• Host interface pins are active for wake-up
This leads to the lowest possible power consumption of
MGC3130.
The MGC3130 will resume from Deep Sleep if one of
the following events occurs:
• External Interrupt (IRQ0) or I
2
C0 Start Bit
Detection
• On MCLR Reset
The Deep Sleep mode can be enabled by GestIC
Library messages.
4.2.4.3 Self Wake-up Mode
The Self Wake-up mode is a Low-Power mode allowing
an autonomous wake-up of the MGC3130 and
application host. In this mode, the MGC3130 is
automatically and periodically alternating between
Sleep and Scan phases.
The MGC3130’s fast wake-up, typically below 1 ms,
allows to perform scans in very efficient periods and to
maximize the Sleep phase.
The periodic Wake-up sequence is triggered by a
programmable wake-up timer running at LSO
frequency and which can be adjusted by the Approach
Detection feature.
The MGC3130 enters the Self Wake-up mode by a
GestIC Library message or by a non-activity time-out.
Non-activity means no user detection within the
sensing area.
The MGC3130 will resume from Self Wake-up on one
of the following events:
• Wake-up timer overflow event
• External Interrupt (IRQ0) or I
2
C0 Start Bit
detection
• On MCLR or WDTR