AN1965 Freescale Semiconductor / Motorola, AN1965 Datasheet
AN1965
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AN1965 Summary of contents
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... State Diagram ............................... 12 6.3.1 Application State Machine ....... 12 7. Software Implementation ............ 13 7.1 Embedded Beans .......................... 13 7.2 Bean Modules ............................... 14 7.3 PFC Control Integration ............... 16 7.3.1 Resources ................................. 16 7.3.2 Modification ............................. 16 7.4 PFC Control Constants ................. 16 7.5 PFC Control API .......................... 17 7.5.1 PFC_Init ................................... 17 7.5.2 PFC_SetUOut........................... 17 7.5.3 PFC_Enable.............................. 18 7.5.4 PFC_Disable ............................ Master Software .................... 18 9. References ................................... 19 Go to: www.freescale.com Order by AN1965/D (Motorola Order Number) Rev. 1.0, 12/2003 Contents ...
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Freescale Semiconductor, Inc. Motorola Hybrid Controller Advantages and Features This application note presents the concept of the continuous conduction current mode boost PFC with nominal output power of 180W. The PFC is digitally controlled by a hybrid controller. 2. Motorola ...
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Freescale Semiconductor, Inc. • Integral reload rates from one to 16 • Individual software-controlled PWM outputs • Programmable fault protection • Polarity control • 20-mA current sink capability on PWM pins • Write-protectable registers The PWM outputs are configured in ...
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Freescale Semiconductor, Inc. Power Factor Correction (PFC) Theory ~115V 60Hz ~230V 50Hz Zero crossing Zero-crossing Pulse Width detection Detection Modulation Input Frequency Frequency Measurement Milestone Generation The Control Process The PFC performs correction of the input current waveform. The standard ...
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Freescale Semiconductor, Inc. Standard Power Supply: Output voltage Input current Figure 3-2. Waveforms of Output Voltage and Input Current To produce the rectangular input current waveform, an active PFC is placed between the rectifier and the filtering capacitor. This is ...
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Freescale Semiconductor, Inc. System Design Concept This hardware implementation does not allow direct modification of the pulse duty cycle that feeds to the switcher (T). The reference voltage of the external PWM comes from a filtered PWM signal from the ...
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Freescale Semiconductor, Inc. Milestone 1 Milestone 2 Deactivate inhibit Activate inhibit Read V out PID regulator Program PWM Figure 4-1. Indirect PFC Control Flowchart Initialization - Initializes the on-chip peripherals, power line voltage and frequency detection Input capture event handler ...
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Freescale Semiconductor, Inc. Hardware Implementation PWM signal, the analog voltage is obtained. It corresponds with the required input current, fed to the analog comparator (the external Pulse Width Modulator) switching the MOSFET. The control technique is based on the hysteresis ...
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Freescale Semiconductor, Inc. The hardware set-up shown in Platform manual, available from Motorola. See the appropriate EVM manual for a description of jumper settings. 5.2 High Voltage Hardware Set The PFC application does not require a motor drive as it ...
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Freescale Semiconductor, Inc. Software Design 6. Software Design This section describes the design of the drive’s software blocks. The software will be described in terms of: • Calculating reference voltage • Processing milestones • State diagram 6.1 Calculating Reference Voltage ...
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Freescale Semiconductor, Inc. 6.2 Milestone Generation The reference voltage value is corrected during the period of input voltage to provide the input current waveform illustrated in Figure zero-crossing pulse length and synchronizes the processes of milestone generation with input frequency; ...
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Freescale Semiconductor, Inc. Software Design invokes function from the Milestone Callback Table, which performs calculation and correction of PFC reference value or activates inhibit output. This procedure allows easy modification of the sequence of events. 6.3 State Diagram PFC control ...
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Freescale Semiconductor, Inc. No Faults Switch ON Enable PFC Control Figure 6-4. Application State Machine 7. Software Implementation This project is implemented using Processor Expert plug-in and Embedded Beans™ technology in the CodeWarrior Integrated Devolopment Environment (IDE). Processor Expert is ...
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Freescale Semiconductor, Inc. Software Implementation 7.2 Bean Modules Each peripheral on the hybrid controller chip or on the EVM board is accessible through a bean. Processor Expert generates the source code modules containing the implementation of methods controlling the hardware ...
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Freescale Semiconductor, Inc. Table 7-1. Beans Used in Implementing the 56F805 Bean name Bean type PC_M1 PC_Master adcPrimary PI_ADC tmrD2 PI_TMR tiAux TimerInt Figure 7-2. Beans Used in Implementing the 56F8346 Indirect Power Factor Correction 15 For More Information On ...
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Freescale Semiconductor, Inc. Software Implementation Table 7-2. Beans Used in Implementing the 56F8346 Bean name Bean type PC_M1 PC_Master adcPrimary PI_ADC tmrD1 PI_TMR tiAux TimerInt 7.3 PFC Control Integration 7.3.1 Resources PFC control uses some of the hybrid controller’s peripherals ...
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Freescale Semiconductor, Inc. MilestoneTime is the array of the milestones’ time intervals. Its values depend on the current waveform to be generated. The MKS_TO_TICK() macro allows the definition value to be expressed in microseconds. Example: const UWord16 MilestoneTime[] ={ MKS_TO_TICK(411L), ...
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Freescale Semiconductor, Inc. PC Master Software 7.5.3 PFC_Enable Prototype: void PFC_Enable(void); This function enables PFC control to start the conversion after the first zero-crossing pulse. Notes: Do not enable PFC control until measurement of DCBus voltage is complete. 7.5.4 PFC_Disable ...
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Freescale Semiconductor, Inc. The PC master software Control Page is illustrated in be seen in the Speed Scope window. 9. References DSP56800 16-Bit Digital Signal Processor Family Manual, DSP56F800FM/D, Motorola DSP56800E 16-Bit Digital Signal Processor Reference Manual, DSP56800ERM/D, Motorola 56F805 ...
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... Office. digital dna is a trademark of Motorola, Inc. This product incorporates SuperFlash® technology licensed from SST. All other product or service names are the property of their respective owners. Motorola, Inc Equal Opportunity/Affirmative Action Employer. © Motorola, Inc. 2003 AN1965/D Go to: www.freescale.com ...