Arm Enterprises IM-AD1 manual PWM controller

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Reference Design Example

4.6PWM controller

The PWM control function is implemented by the DC-DC converter PrimeCell (PL160). Refer to the ARM PrimeCell DC-DC Converter Interface (PL160) Technical Reference Manual for information about this device.

The DC-DC PrimeCell uses the 4MHz IM_CLK signal to supply the DCDCCLK reference clock. It can divide this by 16, 32, 128, or 304 to provide four possible switching frequencies of 250kHz, 125kHz, 31.25kHz, and 13.158kHz.

The switching circuitry has turn on and turn off delays that limit the minimum pulse width and can also affect the accuracy of the PWM, particularly at the higher switching frequencies between 125kHz to 250kHz. The turn on and turn off delays for different voltages are shown in Table 4-9.

Table 4-9 PWM turn on and turn off delays

Load voltage	Turn on time	Turn off time

5V	1μs	0.6μs

30V	2μs	1.2μs

4-16

Copyright © 2001-2003. All rights reserved.

ARM DUI 0163B

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Contents Integrator/IM-AD1 Integrator/IM-AD1 User GuideConformance Notices Copyright 2001-2003. All rights reserved Integrator/IM-AD1 User Guide Chapter IntroductionAppendix a Signal Descriptions Preface Intended audience Using this bookAbout this book ARM publications Typographical conventionsFurther reading Third-party documents Feedback on the Integrator/IM-AD1 FeedbackFeedback on this document Xii Introduction About the Integrator/IM-AD1 ARM DUI 0163BIntegrator/IM-AD1 layout Interface module features and architecture FeaturesIntegrator/IM-AD1 block diagram ArchitectureConfig LED Links and LEDsCare of modules Introduction Copyright 2001-2003. All rights reserved Getting Started Fitting the interface module Assembled Integrator development systemSetting up the logic module Switch 2 Closed Switch 3 Open Switch 4 OpenRunning the test software Hardware Reference Hardware Reference Uart interface Serial interface signal assignment Signal nameConnector DescriptionSerial connector pinout Serial connector signal assignment Pin J18 Type DescriptionSPI signals Signal SPIPWM interface signals Signal PWM interfaceShows the signal assignment PWM connector signals Pin J14 J10 DescriptionStepper motor interface Functional descriptionStepper motor interface signal summary Therefore, with a 0.1Ω sense resistor fittedStepper motor connectors Stepper motor interface signalsStepper motor connector signals Pin J19 J23 Description VSSGpio connectors J16 and J17 GpioHardware Reference Buffer Can interfaceU13 Can interface signal assignment Signal IMBBANK30 IMBBANK28IMBBANK29 Can connector signal assignments Pin GNDADC and DAC interfaces 10 ADC and DAC interface architectureIMABANK50 IMABANK48IMABANK49 IMABANK5111shows the pinout of the ADC interface connector J1 12 shows the pinout of the DAC interface connector J2 Hardware Reference Copyright 2001-2003. All rights reserved Reference Design Example Example architecture About the design exampleAbout PrimeCells Vhdl file descriptions File DescriptionExample memory map Address assignment of logic modules Integrator system memory mapIntegrator/IM-AD1 memory map Device Address Integrator/IM-AD1 memory mapLogic module addresses Position Bits Stack Gpiob StepperbGpioa SsramOffset address Name Type Function Example APB register peripheralLogic module registers Oscillator divisor registers VDW LMOSCx registers Bits Name Access FunctionRDW User LEDs control register Bits Name Access FunctionOscillator lock register Push button interrupt registerSwitches register Uart SPICS1 SPI chip select registerSPICS2 SPICS0Synchronous serial port PWM controller Cont Offset Name Access Function AddressStepper motor peripheral CountStepper x control register DIR DocountSinglestep Stepx count register Stepx speed registerData output set register Read data output pinsAddress offset Name Access Size Function Read data input registerData direction Gpio direction control 1 bitSsram interface Interrupt Interrupt source Source number Vectored interrupt controllerInterrupt sources CAN1Reference Design Example Can controller interface Can reset control registerCanreset CANxBaseAdcstatus ADC and DAC interface16 ADC and DAC interface registers ADC2BUSYBits Name Function Peripheral information block18 PIB entry format Signal Descriptions Expa Table A-1 AHB signal assignment Pin label Signal DescriptionExpb Table A-2 Expb signal description Pin label Name DescriptionExpim LM-EP20K1000E Description Table A-3 Expim signal descriptionsLabel Logic analyzer connector Figure A-4 J7 pin locationsTable A-4 J7 connector pinout Signal Pin CLK1Figure A-5 Multi-ICE connector pinout Multi-ICE JtagMechanical Specification Figure B-1 Board dimensions top view Mechanical informationFigure B-2 Bottom board dimensions viewed from top side DB9STRAIGHT FCI Connector referenceDB9DUAL Glossary Multi-ICESynchronous Serial Port DAC IndexADC Can GpioLmleds Lmlock LMOSC1 Expa A-2Gpiodataclr Gpiodatain Gpiodataout Gpiodataset Gpiodirn