UCD3138: UCD3138的DPWM谐振模式无输出问题

在经过学习LAB1-4的代码学习之后，已经可以对定频变占空比的DPWM波形进行配置。

目前想从LAB3的基础上改为开环调频代码吗，通过CPU_sample的值更改输出DPWM的频率，

但是通过代码发现当DPWM的模式选择为谐振模式时，没有PWM输出；当选择为普通模式时，有PWM输出。

请问配置谐振模式时，还需要注意哪些寄存器？

//###########################################################################
//
// FILE:  main.c
//
// TITLE: main
//
// NOTES:
//  1)

//###########################################################################
//
//  Ver  | dd mmm yyyy | Who  | Description of changes
// ======|=============|======|==============================================
//  1.00 | 05 May 2015 | CH|
//
//  Texas Instruments, Inc
//  Copyright Texas Instruments 2008. All rights reserved.
//###########################################################################
#define MAIN 1

#include "system_defines.h"
#include "Cyclone_Device.h"
#include "pmbus_commands.h"
#include "pmbus_common.h"
#include "pmbus_topology.h"
#include "variables.h"
#include "functions.h"
#include "software_interrupts.h"
#include "cyclone_defines.h"
#include "stdio.h"
#include "pmbus_topology.h"


#define PCLK_PERIOD		4.0e-9
#define DPWM_max200.0e3
#define DPWM_min100.0e3
#define Prd_min(int)(1/(DPWM_max * PCLK_PERIOD))
#define Prd_max(int)(1/(DPWM_min * PCLK_PERIOD))
#define deadtime  (int)(25)		//

int ram_cpu_sample;
// comment for hyperknob [min=0, max=255, step=2]


void init_dpwm0(void)
{Dpwm0Regs.DPWMCTRL0.bit.PWM_EN = 0;				//
	Dpwm0Regs.DPWMCTRL0.bit.CLA_EN = 1;						//
	Dpwm0Regs.DPWMCTRL0.bit.PWM_MODE = 1;				//
	Dpwm0Regs.DPWMCTRL2.bit.RESON_DEADTIME_COMP_EN = 1;		//



	Dpwm0Regs.DPWMEV1.bit.EVENT1 = deadtime;
	Dpwm0Regs.DPWMEV2.bit.EVENT2 = deadtime*16 + Prd_min*0.5*16 - deadtime*16;
	Dpwm0Regs.DPWMEV3.bit.EVENT3 = deadtime*16 + Prd_min*0.5*16 + deadtime*16;
	Dpwm0Regs.DPWMEV4.bit.EVENT4 = (Prd_min - deadtime)*16;
	Dpwm0Regs.DPWMPRD.bit.PRD= Prd_min;



	Dpwm0Regs.DPWMSAMPTRIG1.bit.SAMPLE_TRIGGER = 0;		//
	Dpwm0Regs.DPWMSAMPTRIG1.all = 2000; 				//
	Dpwm0Regs.DPWMCTRL2.bit.SAMPLE_TRIG_1_EN = 1; 		//
	Dpwm0Regs.DPWMCTRL1.bit.EVENT_UP_SEL = 1; 			//Dpwm0Regs.DPWMCTRL0.bit.PWM_EN = 1;			// 
//  Dpwm0Regs.DPWMRESDUTY.bit.RESONANT_DUTY = 2000;Dpwm0Regs.DPWMCTRL2.bit.FILTER_DUTY_SEL = 2;



}





void init_filter0(void)
{

// special set up for CPU SAMPLE - all coefficients are zeroed except for P.
	Filter0Regs.FILTERCTRL.bit.USE_CPU_SAMPLE = 1; 	// 
	Filter0Regs.CPUXN.bit.CPU_SAMPLE = 64; 			// 
	//----------------------------------------------------------------------------------
	// lab 3 tasks:
	// place values on the three filter coefficients (KP, KI and KD) and Kalpha
	// - initialize Kp so as Xn passes through the proportinal branch unchanged
	// - initialize Ki and Kd as the the integral and differential branches are disabled
	// - initialize Kalpha so as the Kalpha pole has no influence on the differential branch
	// place value on the integrator KDALPHA coefficient also
	//----------------------------------------------------------------------------------
	Filter0Regs.FILTERKPCOEF0.bit.KP_COEF_0 = 0x7fff; //full pass through of XN value.
	Filter0Regs.FILTERKICOEF0.bit.KI_COEF_0 = 0.0;
	Filter0Regs.FILTERKDCOEF0.bit.KD_COEF_0 = 0.0;
	Filter0Regs.FILTERKDALPHA.bit.KD_ALPHA_0 = 0.0;Filter0Regs.FILTERCTRL.bit.FILTER_EN = 1;		////enable OK here, because nothing will happen until DPWM and front end are globally enabled

//	Filter0Regs.FILTEROCLPHI.bit.OUTPUT_CLAMP_HIGH = 0x7FFFFF;
//	Filter0Regs.FILTEROCLPLO.bit.OUTPUT_CLAMP_LOW = 0;


//  Better option for handling shoot through - uses full dynamic range of filter
	LoopMuxRegs.FILTERKCOMPA.bit.KCOMP0 = 1000; 			// KCOMP is at 4 ns, period is at 250 ps
	Filter0Regs.FILTERCTRL.bit.PERIOD_MULT_SEL = 1; 		// select kcomp for output multiplier

}





void init_loop_mux(void)
{
	LoopMuxRegs.DPWMMUX.bit.DPWM0_FILTER_SEL = 0; 		// use filter 0 for DPWM 0
	LoopMuxRegs.SAMPTRIGCTRL.bit.FE0_TRIG_DPWM0_EN = 1; // use DPWM0 for filter0 sample trigger
}

void global_enable(void)
{
	union GLBEN_REG glben_store; // collect global enable bits for simultaneous use
	glben_store.all = 0;
	glben_store.bit.DPWM0_EN = 1;
	glben_store.bit.FE_CTRL0_EN = 1;
	LoopMuxRegs.GLBEN = glben_store;
}



void main()
{
	// enable JTAG
	MiscAnalogRegs.IOMUX.all = 0;

	//---------------------------------------------------------------------------
	// IMPORTANT: READ BELOW, OR CODE MAY NOT EXECUTE CORRECTLY
	//---------------------------------------------------------------------------
	// tie pin FAULT2 to ground for normal operation
	// tie pin FAULT2 to 3.3V to clear checksum
	if(GioRegs.FAULTIN.bit.FLT2_IN == 1)
	{
		clear_integrity_word();
	}

#if (UCD3138|UCD3138064)
	MiscAnalogRegs.CLKTRIM.bit.HFO_LN_FILTER_EN = 0;
	MiscAnalogRegs.CSTRIM.bit.RESISTOR_TRIM =23; //28;
#endif

	init_pmbus(0x58);						// initialize PMBus handler
	init_dpwm0();							// initialize DPWM0
	init_filter0();
	init_loop_mux();
	global_enable();
	ram_cpu_sample = Filter0Regs.CPUXN.bit.CPU_SAMPLE; 		// initialize hyperknob
	for(;;)
	{
		pmbus_handler();
		Filter0Regs.CPUXN.bit.CPU_SAMPLE = ram_cpu_sample; 	// put hyperknob value into register
	}
}


//#pragma INTERRUPT(c_int00,RESET)


void c_int00(void)
{
	main();
}

Jie Wang：

通过PMBus查看寄存器值，发现在变占空比可以正常输出pwm时，寄存器xn=cpu_sample；但是当配置为谐振模式时，无论Cpu_sample怎么改变，xn一直等于0

,

Johnsin Tao：

HI

     关于程序，建议你在美国E2E上问一下： https://e2e.ti.com/

     TI  UCD数字电源程序是对外保密的，并且没有提供说明文档，只有签NDA保密协议才能拿到，我们也是没有的。所以建议你在美国E2E上问一下，或者找你购买芯片的渠道看能否签协议拿到例程。