MSP430F6779A Datasheet, PDF (75/176 Pages) Texas Instruments – Polyphase Metering SoCs

www.ti.com
MSP430F6779A, MSP430F6778A, MSP430F6777A, MSP430F6776A, MSP430F6775A
MSP430F6769A, MSP430F6768A, MSP430F6767A, MSP430F6766A, MSP430F6765A
MSP430F6749A, MSP430F6748A, MSP430F6747A, MSP430F6746A, MSP430F6745A
SLAS982 – MAY 2014
6.11 Peripherals
Peripherals are connected to the CPU through data, address, and control buses and can be handled using
all instructions. For complete module descriptions, see the MSP430x5xx and MSP430x6xx Family User's
Guide (SLAU208).
6.11.1 Oscillator and System Clock (Link to User's Guide)
The Unified Clock System (UCS) module includes support for a 32768-Hz watch crystal oscillator, an
internal very-low-power low-frequency oscillator (VLO), an internal trimmed low-frequency oscillator
(REFO), and an integrated internal digitally controlled oscillator (DCO). The UCS module is designed to
meet the requirements of both low system cost and low power consumption. The UCS module features
digital frequency locked loop (FLL) hardware that, in conjunction with a digital modulator, stabilizes the
DCO frequency to a programmable multiple of the selected FLL reference frequency. The internal DCO
provides a fast turn-on clock source and stabilizes in less than 5 µs. The UCS module provides the
following clock signals:
• Auxiliary clock (ACLK), sourced from a 32768-Hz watch crystal, the internal low-frequency oscillator
(VLO), or the trimmed low-frequency oscillator (REFO).
• Main clock (MCLK), the system clock used by the CPU. MCLK can be sourced by same sources made
available to ACLK.
• Sub-Main clock (SMCLK), the subsystem clock used by the peripheral modules. SMCLK can be
sourced by same sources made available to ACLK.
• ACLK/n, the buffered output of ACLK, ACLK/2, ACLK/4, ACLK/8, ACLK/16, ACLK/32.
6.11.2 Power Management Module (PMM) (Link to User's Guide)
The PMM includes an integrated voltage regulator that supplies the core voltage to the device and
contains programmable output levels to provide for power optimization. The PMM also includes supply
voltage supervisor (SVS) and supply voltage monitoring (SVM) circuitry, as well as brownout protection.
The brownout circuit is implemented to provide the proper internal reset signal to the device during power-
on and power-off. The SVS/SVM circuitry detects if the supply voltage drops below a user-selectable level
and supports both supply voltage supervision (the device is automatically reset) and supply voltage
monitoring (the device is not automatically reset). SVS and SVM circuitry is available on the primary
supply and core supply.
6.11.3 Auxiliary Supply System (Link to User's Guide)
The auxiliary supply system provides the option to operate the device from auxiliary supplies when the
primary supply fails. There are two auxiliary supplies (AUXVCC1 and AUXVCC2) supported in
MSP430F67xx. This module supports automatic and manual switching from primary supply to auxiliary
supplies while maintaining full functionality. It allows threshold-based monitoring of primary and auxiliary
supplies. The device can be started from primary supply or AUXVCC1, whichever is higher. Auxiliary
supply system enables internal monitoring of voltage levels on primary and auxiliary supplies using
ADC10_A. This module also implements a simple charger for backup capacitors.
6.11.4 Backup Subsystem (Link to User's Guide)
The Backup subsystem operates on a dedicated power supply AUXVCC3. This subsystem includes low-
frequency oscillator, Real-Time Clock module, and Backup RAM. The functionality of Backup subsystem is
retained during LPM3.5. The Backup subsystem module registers cannot be accessed by CPU when the
high side SVS is disabled by user.
Copyright © 2014, Texas Instruments Incorporated
Detailed Description
75
Submit Documentation Feedback
Product Folder Links: MSP430F6779A MSP430F6778A MSP430F6777A MSP430F6776A MSP430F6775A
MSP430F6769A MSP430F6768A MSP430F6767A MSP430F6766A MSP430F6765A MSP430F6749A
MSP430F6748A MSP430F6747A MSP430F6746A MSP430F6745A