PWM Scaling UG0656 User Guide Table of Contents Introduction ....................................................................................................................3 Hardware Implementation .............................................................................................4 Inputs and Outputs ........................................................................................................................................ 4 Configuration Parameters .............................................................................................................................. 5 Resource Utilization ....................................................................................................................................... 5 List of Changes ..............................................................................................................6 Product Support.............................................................................................................7 Customer Service .......................................................................................................................................... 7 Customer Technical Support Center ............................................................................................................. 7 Technical Support .......................................................................................................................................... 7 Website .......................................................................................................................................................... 7 Contacting the Customer Technical Support Center ..................................................................................... 7 ITAR Technical Support ................................................................................................................................ 8 2 UG0656: PWM Scaling User Guide Introduction PWM scaling is used to scale down the voltages computed from field oriented control (FOC) to fit within the PWM carrier wave magnitude range. It also adds a bias to shift negative voltages to positive level. The PWM scaling performs the following functions: • • Scales phase voltages according to the following equation: Vph_o = ((pwm_period_i ∗ 32768) + (pwm_gain_i ∗ Vph_i )/2)/65536 EQ1 To use the advantage of voltage boost provided by space vector modulation (SVM), pwm_gain_i can be multiplied by a factor of 1.15 as the following:: pwm_gain_i = (pwm_period_i ∗ 1182)/1024 UG0656: PWM Scaling User Guide EQ2 3 Hardware Implementation Figure 1 shows the block diagram of PWM scaling. reset_i sys_clk_i va_o start_i va_i vb_i vb_o PWM Scaling vc_o vc_i done_o pwm_period_i pwm_gain_i Figure 1. System-level Block Diagram of PWM Scaling The PWM scaling calculates scaled phase voltages according to the EQ1. The number of clock cycles between the start_i and done_o is 8 for g_NO_MCYCLE_PATH value of 2. The time between two successive start signals should be at least 8 clock cycles. Inputs and Outputs Table 1 shows the input and output ports of PWM scaling. Table 1. Inputs and Outputs of PWM Scaling Signal Name Direction Description reset_i Input Active low asynchronous reset signal sys_clk_i Input System clock start_i Input Start signal to start module computation - should be high for one system clock cycle va_i Input Phase A voltage input vb_i Input Phase B voltage input vc_i Input Phase C voltage input pwm_period_i Input PWM period value in terms of system clock pwm_gain_i Input PWM gain input as calculated from equation 2 va_o Output Scaled phase A voltage output vb_o Output Scaled phase B voltage output vc_o Output Scaled phase C voltage output done_o Output Indicates completion of scaling operations - high for one clock cycle UG0656: PWM Scaling User Guide 4 Hardware Implementation Configuration Parameters Table 2 shows the description of the configuration parameters used in the hardware implementation of PWM scaling. These are generic parameters and can be varied as per the requirement of the application. Table 2. Configuration Parameters Signal Name Description g_STD_IO_WIDTH Defines the width of the input and output signals g_NO_MCYCLE_PATH Defines the number of clock delays required before asserting the multiplier done signal. Resource Utilization ® PWM scaling is implemented on the SmartFusion 2 system-on-chip (SoC) field programmable gate array (FPGA) ® and IGLOO 2 devices. Table 3 shows the resource utilization report after synthesis with g_STD_IO_WIDTH value equal to 18. Table 3. Resource Utilization Report of PWM Scaling Cell Usage Count SLE (Sequential) 81 Combinational Logic 47 MACC 1 RAM1Kx18 0 RAM64x18 0 UG0656: PWM Scaling User Guide 5 List of Changes The following table shows important changes made in this document for each revision. Date and Revision Revision 1 (October 2015) Change Initial release. UG0656: PWM Scaling User Guide Page N/A 6 Product Support Microsemi SoC Products Group backs its products with various support services, including Customer Service, Customer Technical Support Center, a website, electronic mail, and worldwide sales offices. This appendix contains information about contacting Microsemi SoC Products Group and using these support services. Customer Service Contact Customer Service for non-technical product support, such as product pricing, product upgrades, update information, order status, and authorization. From North America, call 800.262.1060 From the rest of the world, call 650.318.4460 Fax, from anywhere in the world 650. 318.8044 Customer Technical Support Center Microsemi SoC Products Group staffs its Customer Technical Support Center with highly skilled engineers who can help answer your hardware, software, and design questions about Microsemi SoC Products. The Customer Technical Support Center spends a great deal of time creating application notes, answers to common design cycle questions, documentation of known issues and various FAQs. So, before you contact us, please visit our online resources. It is very likely we have already answered your questions. Technical Support For Microsemi SoC Products Support, visit http://www.microsemi.com/products/fpga-soc/design-support/fpga-socsupport. Website You can browse a variety of technical and non-technical information on the Microsemi SoC Products Group home page, at http://www.microsemi.com/products/fpga-soc/fpga-and-soc. Contacting the Customer Technical Support Center Highly skilled engineers staff the Technical Support Center. The Technical Support Center can be contacted by email or through the Microsemi SoC Products Group website. Email You can communicate your technical questions to our email address and receive answers back by email, fax, or phone. Also, if you have design problems, you can email your design files to receive assistance. We constantly monitor the email account throughout the day. When sending your request to us, please be sure to include your full name, company name, and your contact information for efficient processing of your request. The technical support email address is [email protected]. My Cases Microsemi SoC Products Group customers may submit and track technical cases online by going to My Cases. UG0656: PWM Scaling User Guide 7 Product Support Outside the U.S. Customers needing assistance outside the US time zones can either contact technical support via email ([email protected]) or contact a local sales office. Visit About Us for sales office listings and corporate contacts. ITAR Technical Support For technical support on RH and RT FPGAs that are regulated by International Traffic in Arms Regulations (ITAR), contact us via [email protected]. Alternatively, within My Cases, select Yes in the ITAR drop-down list. For a complete list of ITAR-regulated Microsemi FPGAs, visit the ITAR web page. 8 UG0656: PWM Scaling User Guide Microsemi Corporation (Nasdaq: MSCC) offers a comprehensive portfolio of semiconductor and system solutions for communications, defense & security, aerospace and industrial markets. Products include high-performance and radiation-hardened analog mixed-signal integrated circuits, FPGAs, SoCs and ASICs; power management products; timing and synchronization devices and precise time solutions, setting the world's standard for time; voice processing devices; RF solutions; discrete components; security technologies and scalable anti-tamper products; Ethernet solutions; Power-over-Ethernet ICs and midspans; as well as custom design capabilities and services. Microsemi is headquartered in Aliso Viejo, Calif., and has approximately 3,600 employees globally. Learn more at www.microsemi.com. Microsemi Corporate Headquarters One Enterprise, Aliso Viejo, CA 92656 USA Within the USA: +1 (800) 713-4113 Outside the USA: +1 (949) 380-6100 Sales: +1 (949) 380-6136 Fax: +1 (949) 215-4996 E-mail: [email protected] © 2015 Microsemi Corporation. All rights reserved. Microsemi and the Microsemi logo are trademarks of Microsemi Corporation. All other trademarks and service marks are the property of their respective owners. Microsemi makes no warranty, representation, or guarantee regarding the information contained herein or the suitability of its products and services for any particular purpose, nor does Microsemi assume any liability whatsoever arising out of the application or use of any product or circuit. The products sold hereunder and any other products sold by Microsemi have been subject to limited testing and should not be used in conjunction with mission-critical equipment or applications. Any performance specifications are believed to be reliable but are not verified, and Buyer must conduct and complete all performance and other testing of the products, alone and together with, or installed in, any end-products. Buyer shall not rely on any data and performance specifications or parameters provided by Microsemi. It is the Buyer’s responsibility to independently determine suitability of any products and to test and verify the same. The information provided by Microsemi hereunder is provided “as is, where is” and with all faults, and the entire risk associated with such information is entirely with the Buyer. Microsemi does not grant, explicitly or implicitly, to any party any patent rights, licenses, or any other IP rights, whether with regard to such information itself or anything described by such information. Information provided in this document is proprietary to Microsemi, and Microsemi reserves the right to make any changes to the information in this document or to any products and services at any time without notice. 50200656-1/10.15