Texas Instruments 28xxx manual One-Shot Pulse, Possible Pulse Width Values for Sysclkout = 100 MHz

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PWM-Chopper (PC) Submodule

2.6.4.1One-Shot Pulse

The width of the first pulse can be programmed to any of 16 possible pulse width values. The width or period of the first pulse is given by:

T1stpulse = TSYSCLKOUT × 8 × OSHTWTH

Where TSYSCLKOUT is the period of the system clock (SYSCLKOUT) and OSHTWTH is the four control bits (value from 1 to 16)

Figure 2-33shows the first and subsequent sustaining pulses and Table 7.3 gives the possible pulse width values for a SYSCLKOUT = 100 MHz.

Figure 2-33. PWM-Chopper Submodule Waveforms Showing the First Pulse and Subsequent Sustaining

Pulses

Start OSHT pulse

EPWMxA in

PSCLK

Prog. pulse width (OSHTWTH)

OSHT

EPWMxA out

Sustaining pulses

Table 2-16. Possible Pulse Width Values for

SYSCLKOUT = 100 MHz

OSHTWTHz	Pulse Width
(hex)	(nS)
0	80
1	160
2	240
3	320
4	400
5	480
6	560
7	640
8	720
9	800
A	880
B	960
C	1040
D	1120
E	1200
F	1280

SPRU791D–November 2004–Revised October 2007

ePWM Submodules

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Contents Reference Guide Submit Documentation Feedback Contents Controlling a 3-Phase Interleaved DC/DC Converter List of Figures Event-Trigger Socb Pulse Generator Simplified ePWM Module List of Tables Submit Documentation Feedback Data Manuals Related Documentation From Texas InstrumentsCPU Users Guides Peripheral GuidesApplication Reports Tools GuidesTMS320C28x, C28x are trademarks of Texas Instruments TrademarksSubmit Documentation Feedback Introduction Submodule Overview IntroductionMultiple ePWM Modules ∙ Trip-zone signals TZ1 to TZ6 ∙ PWM output signals EPWMxA and EPWMxB∙ ADC start-of-conversion signals EPWMxSOCA and EPWMxSOCB ∙ Peripheral BusRegister Mapping EPWM Submodules and Critical Internal Signal InterconnectsDescription Offset Size NameTime-Base Submodule Registers Counter-Compare Submodule RegistersEPWM Submodules Submodule Configuration Parameters Submodule Configuration Parameter or OptionOverview Tbup Example 2-1. Constant Definitions Used in the Code ExamplesChpenable Purpose of the Time-Base Submodule Time-Base TB SubmoduleControlling and Monitoring the Time-base Submodule Time-Base Submodule RegistersRegister ∙ Up-Down-Count Mode Key Time-Base Signals∙ Up-Count Mode ∙ Down-Count Mode∙ Time-Base Period Immediate Load Mode ∙ Time-Base Period Shadow ModeTime-Base Period Shadow Register ∙ Active RegisterTime-Base Counter Synchronization Scheme Time-Base Counter SynchronizationEPWM11SYNCO EPWM11SYNCI∙ Software Forced Synchronization Pulse ∙ EPWMxSYNCI Synchronization Input PulseTime-base Counter Modes and Timing Waveforms Phase Locking the Time-Base Clocks of Multiple ePWM ModulesTime-Base Down-Count Mode Waveforms 11. Counter-Compare Submodule Counter-Compare CC SubmoduleControlling and Monitoring the Counter-Compare Submodule Purpose of the Counter-Compare SubmoduleCounter-Compare Submodule Registers Register Name Address OffsetCounter-Compare Submodule Key Signals Count Mode Timing Waveforms∙ Shadow Mode ∙ Immediate Load ModeCTR=CMPB CTR=CMPACTR = Cmpb Action-Qualifier AQ Submodule Purpose of the Action-Qualifier SubmoduleAction-Qualifier Submodule Registers ∙ Set High Action-Qualifier Submodule Possible Input Events∙ Clear Low ∙ ToggleTB Counter equals Actions Action-Qualifier Event Priority for Up-Count Mode Action-Qualifier Event Priority for Up-Down-Count Mode10. Action-Qualifier Event Priority for Down-Count Mode Action-Qualifier Event PriorityUse up-down-count mode to generate a symmetric PWM Waveforms for Common ConfigurationsUse up-down-count mode to generate an asymmetric PWM When using up-count mode to generate an asymmetric PWM20. Up-Down-Count Mode Symmetrical Waveform Tbctr Example 2-2. Code Sample for FigureValue EPWMxA EPWMxB Tbclk = Sysclkout Example 2-3. Code Sample for FigureEdgePosA Example 2-4. Code Sample for FigureExample 2-5. Code Sample for Figure Tbctr Example 2-6. Code Sample for FigureEPWMxA EPWMxB Example 2-7. Code Sample for FigurePurpose of the Dead-Band Submodule Dead-Band Generator DB SubmoduleControlling and Monitoring the Dead-Band Submodule 12. Dead-Band Generator Submodule RegistersOperational Highlights for the Dead-Band Submodule ∙ Output Mode Control∙ Input Source Selection ∙ Polarity Control13. Classical Dead-Band Operating Modes Mode Description29. Dead-Band Waveforms for Typical Cases 0% Duty 100% FED = Dbfed × Ttbclk RED = Dbred × Ttbclk Dead-Band Delay in μSPurpose of the PWM-Chopper Submodule PWM-Chopper PC SubmoduleControlling the PWM-Chopper Submodule Operational Highlights for the PWM-Chopper Submodule31. PWM-Chopper Submodule Operational Details WaveformsOne-Shot Pulse 16. Possible Pulse Width Values for Sysclkout = 100 MHzOSHTWTHz Period Duty Cycle ControlPurpose of the Trip-Zone Submodule Trip-Zone TZ SubmoduleOperational Highlights for the Trip-Zone Submodule Controlling and Monitoring the Trip-Zone Submodule17. Trip-Zone Submodule Registers ∙ Cycle-by-Cycle CBC18. Possible Actions On a Trip Event Example 2-8. Trip-Zone ConfigurationsScenario a Scenario BGenerating Trip Event Interrupts 36. Trip-Zone Submodule Mode Control Logic37. Trip-Zone Submodule Interrupt Logic Event-Trigger ET SubmoduleOperational Overview of the Event-Trigger Submodule CTR=CMPB CTRD=CMPB 19. Event-Trigger Submodule Registers41. Event-Trigger Interrupt Generator 42. Event-Trigger Soca Pulse Generator Submit Documentation Feedback Controlling Multiple Buck Converters With Independent Applications to Power TopologiesOverview of Multiple Modules Key Configuration CapabilitiesCTR=0 EPWM1B CTR=CMPB Control of Four Buck Stages. Here FPWM1≠ FPWM2≠ FPWM3≠ FPWM4 Buck Waveforms for -3Note Only three bucks shown here 500 Example 3-1. Configuration for Example in FigureControl of Four Buck Stages. Note FPWM2 = N x FPWM1 Controlling Multiple Buck Converters With Same FrequenciesBuck Waveforms for -5Note FPWM2 = FPWM1 Example 3-2. Code Snippet for Configuration in Figure Control of Two Half-H Bridge Stages FPWM2 = N x FPWM1 Controlling Multiple Half H-Bridge HHB ConvertersHalf-H Bridge Waveforms for -7Note Here FPWM2 = FPWM1 Example 3-3. Code Snippet for Configuration in Figure Controlling Dual 3-Phase Inverters for Motors ACI and PmsmEPWM1A 10 -Phase Inverter Waveforms for -9Only One Inverter Shown Example 3-4. Code Snippet for Configuration in Figure 11. Configuring Two PWM Modules for Phase Control Controlling a 3-Phase Interleaved DC/DC Converter Controlling a 3-Phase Interleaved DC/DC Converter13. Control of a 3-Phase Interleaved DC/DC Converter 14 -Phase Interleaved DC/DC Converter Waveforms for Figure Example 3-5. Code Snippet for Configuration in Figure 15. Controlling a Full-H Bridge Stage FPWM2 = FPWM1 16. ZVS Full-H Bridge Waveforms Example 3-6. Code Snippet for Configuration in Figure Submit Documentation Feedback Proper Interrupt Initialization Procedure PWM-Chopper Submodule Control RegisterTrip-Zone Submodule Control and Status Registers Time-Base Submodule Registers Time-Base Phase Register Tbphs Field DescriptionsTime-Base Period Register Tbprd Field Descriptions Time-Base Counter Register Tbctr Field DescriptionsBit Field Value Description Time-Base Control Register Tbctl Field DescriptionsSoftware Forced Synchronization Pulse Counter-Compare Submodule Registers Time-Base Status Register Tbsts Field DescriptionsBit Field Counter-Compare a Register Cmpa Field Descriptions Counter-Compare B Register Cmpb Field DescriptionsBits Name Description Counter-Compare Control Register Cmpctl Field Descriptions Action-Qualifier Submodule RegistersCBD CBU CAD CAU PRD ZRO Bits NameCBD 10. Action-Qualifier Output B Control Register Aqctlb Rldcsf Otsfb Actsfb Otsfa Actsfa RldcsfCsfb Csfa Dead-Band Submodule Registers CsfbInmode Polsel Outmode Inmode 16. PWM-Chopper Control Register Pcctl Bit Descriptions PWM-Chopper Submodule Control RegisterName Value Description ReservedTrip-Zone Submodule Control and Status Registers PWM-Chopper Control Register Pcctl Bit DescriptionsChpduty CBC6 CBC5 CBC4 CBC3 CBC2 CBC1 OSHT6 OSHT5 OSHT4 OSHT3 OSHT2 OSHT1OSHT6 CBC6TZB TZA 18. Trip-Zone Control Register Tzctl Field DescriptionsTZB OST CBCOST CBC INT 20. Trip-Zone Flag Register Tzflg Field DescriptionsEvent-Trigger Submodule Registers 21. Trip-Zone Clear Register Tzclr Field Descriptions22. Trip-Zone Force Register Tzfrc Field Descriptions 23. Event-Trigger Selection Register Etsel Name Description 24. Event-Trigger Prescale Register Etps Field DescriptionsSocb Soca 24. Event-Trigger Prescale Register Etps Field Descriptions25. Event-Trigger Flag Register Etflg Field Descriptions 26. Event-Trigger Clear Register Etclr Field DescriptionsSocb 27. Event-Trigger Force Register Etfrc Field Descriptions Proper Interrupt Initialization Procedure116 Location Modifications, Additions, and Deletions Table A-1. Changes for Revision DAppendix a Important Notice