Building Control Digital Switched-Mode Power Supply (SMPS) Overview The main purpose of a power supply is to provide clean and stable power to a load, regardless of power grid conditions. The SMPS has been widely used in office equipment, computers, communication systems and other applications because of its high efficiency and high energy density. EXAMPLE DIGITAL SMPS L1 L2 D1 V+ C2 D3 T2 Q1 C3 GND2 T4 D4 T3 GND2 Shunt If Vsynch AN0 PWM AN1 56F801 If AN2 Current Regulator Vref L3 V- PWM1 Voltage Regulator D5 GND1 Vf Current Regulator SCI > Intelligent mode management and fault supervision > Lower system and maintenance cost C1 AC110V or AC220V > High input power factor lowers power pollution to the power grid > Operating status can be monitored and controlled in real time D2 T1 Key Benefits > Power applications become more flexible and universal SCI Vf AN0 AN1 Voltage Regulator 56F8323 Vref SCI Freescale Ordering Information Part Number Product Highlights Additional Information DSP56F801 80 MHz, 40 MIPS, SCI, SPI, ADC, PWM, Quad Timer and > 8K Program Flash > 1K Program RAM > 2K Data Flash > 1K Data RAM MCU-friendly instruction set, OnCE for debug, on-chip relaxation oscillator, 2K BootFLASH and up to 11 GPIO available in a 48-pin LQFP. DSP56F802 80 MHz, 40 MIPS, SCI, SPI, ADC, PWM, Quad Timer and > 8K Program Flash > 1K Program RAM > 2K Data Flash > 1K Data RAM MCU-friendly instruction set, OnCE for debug, on-chip relaxation oscillator, 2K BootFLASH and up to 4 GPIO available in a 32-pin LQFP. DSP56F803 80 MHz, 40 MIPS, CAN, SCI, SPI, ADC, PWMs, Quadrature Decoder, Quad Timer and > 31.5K Program Flash > 512K Program RAM > 4K Data Flash > 2K Data RAM MCU-friendly instruction set, OnCE for debug, on-chip relaxation oscillator,2K BootFLASH, external memory expansion, and up to 16 GPIO available in a 100-pin LQFP. MC56F8322 60 MHz, 60 MIPS, 2 SPI, 2 SCI, 2 ADC, PWM, COP, PLL, Decoder, 2 Quad Timers, FlexCAN, an MCU-friendly instruction set, Enhanced OnCE for debug, on-chip relaxation oscillator, and temperature sensor with > 48KB Flash > 12KB RAM Industrial (-40°C to 105°C) and Extended (-40°C to 125°C) Temperature Ranges with up to 21 GPIOs in a 48-pin LQFP MC56F8323 60 MHz, 60 MIPS, 2 SPI, 2 SCI, 2 ADC, PWM, COP, PLL, Decoder, 2 Quad Timers, FlexCAN, an MCU-friendly instruction set, Enhanced OnCE for debug, on-chip relaxation oscillator, and temperature sensor with > 48KB Flash > 12KB RAM Industrial (-40°C to 105°C) and Extended (-40°C to 125°C) Temperature Ranges with up to 27 GPIOs in a 64-pin LQFP Design Challenges Presently, the vast majority of SMPS are implemented in an analog fashion. But analog implementations have significant disadvantages that can be rectified by implementing the SMPS using modern digital mechanisms. Until recently, this has not been cost effective, due to performance and cost of the processors required to do the job. The 56F800 and 56F8300 hybrid controllers specified here have the required performance, peripherals, and price targets to enable SMPS to make the conversion from analog to digital implementations. Freescale Semiconductor Solution The digital 56800/E Switched-Mode Power Supply minimizes the number of system components, maximizes the system reliability, and makes it possible to easily add advanced functions without increasing cost. The performance, integrated peripherals, and low cost of the 56F800 and 56F8300 controllers specified here make the digital SMPS possible and practical. SG2074-2 The system in this example is a 100Watt SMPS controlled by a 56F801 device on the primary side and a 56F8323 on the secondary side. Optional components could include user interfaces, such as an LCD or LED display. During normal operation, an AC/DC rectifier controlled by a 56F801 will correct the input power factor while simultaneously rectifying the AC input voltage. The output of the AC/DC rectifier is a DC voltage that will feed the DC/DC converter, which is controlled by a 56F8323 device. The DC/DC converter has a full bridge topology, used to convert the DC Bus voltage to a precise and constant DC output voltage. For the Power Factor Correction (PFC) converter, the 56F801 samples the input AC voltage, input AC current, and DC output voltage. The output DC voltage is regulated by the 56F801, while maintaining the same phase for both the AC input current and voltage. The PWM module on the 56F801 produces the PWM pulse for the PFC main power component. The DC/DC converter controlled by the 56F8323 is operating on a phase-shifted soft-switching mode, so that switching losses and noise can be kept to a minimum. Control functions implemented within the primary hybrid controller are: > Input power factor correction > Automatic detection of input voltage frequency Control functions implemented within the secondary hybrid controller are: > Power on/off control > DC Bus voltage regulation > Output DC voltage regulation > DC/DC full-bridge phase-shifted control strategy > Power system monitoring and communication protocols (optional) > Fault and mode management Development Tools Tool Type Product Name Vendor Description Software CW568X Freescale Semiconductor CodeWarrior™ Development Studio for 56800/E Hybrid Controllers With Processor Expert (Metrowerks) Hardware MC56F8300DSK Freescale Semiconductor 56F8300 Developers Starter Kit Hardware 56F800DEMO Freescale Semiconductor 56F800 Demonstration kit Hardware DSP56F801EVM Freescale Semiconductor Evaluation Module for 56F801 Processor Hardware DSP56F803EVM Freescale Semiconductor Evaluation Module for 56F803 Processor Hardware MC56F8323EVM Freescale Semiconductor Evaluation Module for 56F8322 and 56F8323 Hybrid Controllers Disclaimer This document may not include all the details necessary to completely develop this design. It is provided as a reference only and is intended to demonstrate the variety of applications for the device. SG2074-3 Notes Learn More: Contact the Technical Information Center at +1-800-521-6247 or +1-480-768-2130. For more information about Freescale products, please visit www.freescale.com. Freescale™ and the Freescale logo are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © Freescale Semiconductor, Inc. 2004. All rights reserved. SG2074 REV 1 12/2004 December2004