Intel PXA27X manual Features of a Pmic, General Pmic Characteristics, Characteristic Description

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Intel® PXA27x Processor Family Power Requirements

Table 9. General PMIC Characteristics

Characteristic

Description

 

 

Highly Integrated,

Incorporating buck, boost, buck-boost, and LDO regulators for the PXA27x processor

Multi-Function

and surrounding system elements, with dynamic voltage management (DVM) logic for

the core supply. It includes power-up, power-down, and sleep mode power sequencing,

 

 

and generates correct nRESET, nBATT_FAULT, and nVDD_FAULT outputs for the

 

system. Ideally, it also incorporates battery charger circuits and an output to notify the

 

system when AC power input is present; touchscreen and audio CODECs would be a

 

plus, if they can meet industry-standard noise and distortion requirements when

 

combined on the same silicon.

 

 

Low-Cost

High integration provides a packaged device that must be lower cost than the

 

alternative comprised of discrete power supply devices.

 

 

High Efficiency

Converters operate in the 85-95% efficiency range under all load conditions, and with

 

very low quiescent current and shutdown currents (off or sleep mode).

 

 

I2C Interface

Must be standard I2C interface operating at either 40 kHz standard mode or 160 kHz

 

fast-mode clock rate.

 

 

Stable and Accurate

Meets ± 3% accuracy or better at the PMIC output signals over input variation, load

 

variation, and temperature for all regulators and converter outputs. Switching

 

regulators must minimize noise propagated into regulator outputs.

 

 

Reliable

Current and thermal limiting on all regulators.

 

 

8.2Features of a PMIC

The basic features of a PMIC for use with the PXA27x processor include:

•Multiple channels of regulated power output

•Dynamic voltage management (DVM) capability for the PXA27x processor core supply

•Debounced push button ON/OFF and user-reset inputs

•AC adapter detect capability

•Power-on / user reset output to the PXA27x processor nRESET input

•nBATT_FAULT signal, signifying main battery removed

•nVDD_FAULT signal, indicating any power regulator out of spec

•Automatic switch over from main battery to backup battery when main battery is discharged or removed

•Responds to the PXA27x processor mode change requests by switching regulators on or off

•Control and Status registers accessible through I2C interface

•Provides USIM power FET control to supply 3.0 V or 1.8 V to USIM card

The features of a PMIC for battery charging also include:

•Charging capability for lithium-ion or lithium-polymer main battery

•Support for either rechargeable or non-rechargeable backup battery

•Digital output battery level monitor (“fuel gauge”) for main and backup batteries (optional)

•Battery charging current and temperature monitoring, for fast charging of main battery (optional)

Application Note

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Contents Application Note Intel PXA27x Processor Family Power RequirementsApplication Note Contents Figures Naming Conventions IntroductionIntel PXA27x Processor Power Supply Domains External Power Supply DescriptionsPower Domain Enable1 Units Specified Levels Tolerance Volts Pxtal PLLSram DMAIntel PXA27x Processor Power Supplies Power Domains and System Voltage/Current RequirementsVoltage Description Intel PXA27x Processor Voltage Domains Sheet 1Intel PXA27x Processor Voltage Domains Sheet 2 Power Supply Configuration in a Minimal SystemRegulators Required to Power the Intel PXA27x Processor Modeling Intel PXA27x processor power consumptionIntel PXA27x Processor Vcccore Supply Current Regulator DescriptionSupply Current For Each Power Domain Frequency Dhrystones Power MPEG4 Decode Power StressIntel PXA27x Processor Vcccore Supply Current Intel PXA27x Processor Supply Current For Each Power Domain Default Reset ValuesName Functional Units Current mA @ Power VccbattMain Battery Backup BatteryBatteries Battery Chargers and Main Power Possible Backup Battery ConfigurationsBackup Battery Description Typical Battery and External Regulator Configuration Intel PXA27x Processor Operating Modes Intel PXA27x Processor Low Power Operating ModesPower Controller Interface Signals CPDIS=1CPDIS=0 System Power Enable Sysen / GPIO2 Power Enable PwrenPower Manager I2C Clock Pwrscl / GPIO3 Power Controller Interface SignalsOn, Off, and Reset Power Manager I2C Data Pwrsda / GPIO4User-Initiated Hard Reset Input System-Level Considerations for I2CPower Manager Capacitor Signals NRESET Output from Pmic to the Intel PXA27x ProcessorUniversal Subscriber Identity Module Usim Power Mode Sequencing Power-OnCold-Start Power-On and Hardware Reset Vcccore Vccpll Vccsram Initial Power Up and Deep Sleep Exit SequenceHardware Reset Behavior Intel PXA27x Processor Family Power Requirements Pwrdel SysdelSleep Entry and Exit Sleep and Deep SleepDeep Sleep Entry and Exit Vcccore Regulator and Dynamic Voltage Management Dynamic Voltage Management DVMIntel PXA27x Processor Voltage Manager Power Manager I2C Interface Fault ManagementNVDDFAULT DVM SequencingPower Management Integrated Circuit Requirements NBATTFAULTGeneral Pmic Characteristics Features of a Pmic General Pmic CharacteristicsCharacteristic Description DVM Control Register Programmable Voltage ControlOther Aspects of an Integrated Power Controller SummaryDVM Control and Status Register Intel PXA27x Processor Family Power Requirements
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