Overview

The MCUXpresso SDK provides a peripheral driver for the DCDC Converter (DCDC) module of MCUXpresso SDK devices.

This section describes the programming interface of the DCDC Converter Peripheral driver.

The DCDC converter module is a switching mode DC-DC converter supporting Buck, Boost, and Bypass mode. It can produce multiple switching outputs for SoC peripherals and external devices with high conversion efficiency. The converter can be operated in continuous or pulsed mode.

As a module to provide the power for hardware system, the DCDC would start working when the system is powered up before the software takes over the SoC. Some important configurations, like selecting BUCK/BOOST/BYPASS mode, is done in the board settings. Before the software can access the DCDC's registers, DCDC are already working normally with the default settings.

However, if the application needs to improve the DCDC's performance or change the default settings, DCDC driver would help. The DCDC's register can not be accessed by software before its initialization (open the clock gate). Then user can configure the hardware according to the application guide from RM.

Function groups

Initialization and deinitialization

This function group is to enable/disable the operations to DCDC module through the driver.

Status

Provides functions to get and clear the DCDC status.

Interrupts

Provides functions to enable/disable DCDC interrupts.

Misc control

Provides functions to set the DCDC's miscellaneous control.

Application guideline

Continuous mode

As guideline from RM, to have better efficiency and ripple. The following call is recommended:

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/dcdc In boost mode, POSLIMIT_BOOST_IN is set to small value by default. To limit startup voltage, set it to 0x12 after startup, to provide high current to output, especially when battery voltage is low. The following call could be used.

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/dcdc

Target voltage adjustment

To adjust target voltage of VDD1P8 and VDD1P5. The following code could be used:

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/dcdc

Pulsed mode

Before entering pulsed mode, the target voltage should be locked. Also, there are some recommended setting.

Refer to the driver examples codes located at <SDK_ROOT>/boards/<BOARD>/driver_examples/dcdc

Data Structures
struct	dcdc_low_power_config_t
	Configuration for the low power. More...

struct	dcdc_loop_control_config_t
	Configuration for the loop control. More...

struct	dcdc_min_power_config_t
	Configuration for min power setting. More...

struct	dcdc_pulsed_integrator_config_t
	Configuration for the integrator in pulsed mode. More...

Macros
#define	FSL_DCDC_DRIVER_VERSION (MAKE_VERSION(2, 0, 4))
	DCDC driver version. More...

Enumerations
enum	_dcdc_status_flags_t { kDCDC_LockedOKStatus = (1U << 0), kDCDC_PSwitchStatus = (1U << 1), kDCDC_PSwitchInterruptStatus = (1U << 2) }
	Status flags. More...

enum	_dcdc_interrupt_enable_t { kDCDC_PSwitchEdgeDetectInterruptEnable = DCDC_REG6_PSWITCH_INT_MUTE_MASK }
	Interrupts. More...

enum	_dcdc_pswitch_detect_event_t { kDCDC_PSwitchFallingEdgeDetectEnable = DCDC_REG6_PSWITCH_INT_FALL_EN_MASK, kDCDC_PSwitchRisingEdgeDetectEnable = DCDC_REG6_PSWITCH_INT_RISE_EN_MASK }
	Events for PSWITCH signal(pin). More...

enum	dcdc_work_mode_t { kDCDC_WorkInContinuousMode = 0U, kDCDC_WorkInPulsedMode = 1U }
	DCDC work mode in SoC's low power condition. More...

enum	dcdc_hysteretic_threshold_offset_value_t { kDCDC_HystereticThresholdOffset0mV = 0U, kDCDC_HystereticThresholdOffset25mV = 1U, kDCDC_HystereticThresholdOffset50mV = 2U, kDCDC_HystereticThresholdOffset75mV = 3U }
	Hysteretic upper/lower threshold value in low power mode. More...

enum	dcdc_vbat_divider_t { kDCDC_VBatVoltageDividerOff = 0U, kDCDC_VBatVoltageDivider1 = 1U, kDCDC_VBatVoltageDivider2 = 2U, kDCDC_VBatVoltageDivider4 = 3U }
	VBAT voltage divider. More...

enum	dcdc_clock_source_t { kDCDC_ClockAutoSwitch = 0U }
	Oscillator clock option. More...

Initialization and deinitialization
void	DCDC_Init (DCDC_Type *base)
	Enable the access to DCDC registers. More...

void	DCDC_Deinit (DCDC_Type *base)
	Disable the access to DCDC registers. More...

Status
uint32_t	DCDC_GetStatusFlags (DCDC_Type *base)
	Get status flags. More...

void	DCDC_ClearStatusFlags (DCDC_Type *base, uint32_t mask)
	Clear status flags. More...

Interrupts
static void	DCDC_EnableInterrupts (DCDC_Type *base, uint32_t mask)
	Enable interrupts. More...

static void	DCDC_DisableInterrupts (DCDC_Type *base, uint32_t mask)
	Disable interrupts. More...

void	DCDC_SetPSwitchInterruptConfig (DCDC_Type *base, uint32_t mask)
	Configure the PSWITCH interrupts. More...

Misc control.
void	DCDC_GetDefaultLowPowerConfig (dcdc_low_power_config_t *config)
	Get the default setting for low power configuration. More...

void	DCDC_SetLowPowerConfig (DCDC_Type base, const dcdc_low_power_config_t config)
	Configure the low power for DCDC. More...

void	DCDC_GetDefaultLoopControlConfig (dcdc_loop_control_config_t *config)
	Get the default setting for loop control configuration. More...

void	DCDC_SetLoopControlConfig (DCDC_Type base, const dcdc_loop_control_config_t config)
	Configure the loop control for DCDC. More...

static void	DCDC_EnableXtalOKDetectionCircuit (DCDC_Type *base, bool enable)
	Enable the XTAL OK detection circuit. More...

static void	DCDC_EnableOutputRangeComparator (DCDC_Type *base, bool enable)
	Enable the output range comparator. More...

static void	DCDC_EnableReduceCurrent (DCDC_Type *base, bool enable)
	Enable to reduce the DCDC current. More...

void	DCDC_SetClockSource (DCDC_Type *base, dcdc_clock_source_t clockSource)
	Set the clock source for DCDC. More...

static void	DCDC_SetBatteryVoltageDivider (DCDC_Type *base, dcdc_vbat_divider_t divider)
	Set the battery voltage divider for ADC sample. More...

void	DCDC_SetBatteryMonitorValue (DCDC_Type *base, uint32_t battValue)
	Set battery monitor value. More...

static void	DCDC_DoSoftShutdown (DCDC_Type *base)
	Software shutdown the DCDC module to stop the power supply for chip. More...

static void	DCDC_SetUpperLimitDutyCycleBuck (DCDC_Type *base, uint32_t value)
	Set upper limit duty cycle limit in DCDC converter in Buck mode. More...

static void	DCDC_AdjustDutyCycleSwitchingTargetOutput (DCDC_Type *base, uint32_t value)
	Adjust value of duty cycle when switching between VDD1P45 and VDD1P8. More...

static void	DCDC_LockTargetVoltage (DCDC_Type *base)
	Lock the setting of target voltage. More...

void	DCDC_AdjustTargetVoltage (DCDC_Type *base, uint32_t vdd1p5xBuck, uint32_t vdd1p8)
	Adjust the target voltage of DCDC output. More...

void	DCDC_GetDefaultMinPowerDefault (dcdc_min_power_config_t *config)
	Get the default configuration for min power. More...

void	DCDC_SetMinPowerConfig (DCDC_Type base, const dcdc_min_power_config_t config)
	Configure for the min power. More...

void	DCDC_GetDefaultPulsedIntegratorConfig (dcdc_pulsed_integrator_config_t *config)
	Get the default setting for integrator configuration in pulsed mode. More...

void	DCDC_SetPulsedIntegratorConfig (DCDC_Type base, const dcdc_pulsed_integrator_config_t config)
	Configure the integrator in pulsed mode. More...

Data Structure Documentation

struct dcdc_low_power_config_t

Data Fields
dcdc_work_mode_t	workModeInVLPRW
	Select the behavior of DCDC in device VLPR and VLPW low power modes. More...

dcdc_work_mode_t	workModeInVLPS
	Select the behavior of DCDC in device VLPS low power modes. More...

bool	enableHysteresisVoltageSense
	Enable hysteresis in low power voltage sense. More...

bool	enableAdjustHystereticValueSense
	Adjust hysteretic value in low power voltage sense. More...

bool	enableHystersisComparator
	Enable hysteresis in low power comparator. More...

bool	enableAdjustHystereticValueComparator
	Adjust hysteretic value in low power comparator. More...

dcdc_hysteretic_threshold_offset_value_t	hystereticUpperThresholdValue
	Configure the hysteretic upper threshold value in low power mode. More...

dcdc_hysteretic_threshold_offset_value_t	hystereticLowerThresholdValue
	Configure the hysteretic lower threshold value in low power mode. More...

bool	enableDiffComparators
	Enable low power differential comparators, to sense lower supply in pulsed mode. More...

Field Documentation

dcdc_work_mode_t dcdc_low_power_config_t::workModeInVLPRW

dcdc_work_mode_t dcdc_low_power_config_t::workModeInVLPS

bool dcdc_low_power_config_t::enableHysteresisVoltageSense

bool dcdc_low_power_config_t::enableAdjustHystereticValueSense

bool dcdc_low_power_config_t::enableHystersisComparator

bool dcdc_low_power_config_t::enableAdjustHystereticValueComparator

dcdc_hysteretic_threshold_offset_value_t dcdc_low_power_config_t::hystereticUpperThresholdValue

dcdc_hysteretic_threshold_offset_value_t dcdc_low_power_config_t::hystereticLowerThresholdValue

bool dcdc_low_power_config_t::enableDiffComparators

struct dcdc_loop_control_config_t

Data Fields
bool	enableDiffHysteresis
	Enable hysteresis in switching converter differential mode analog comparators. More...

bool	enableCommonHysteresis
	Enable hysteresis in switching converter common mode analog comparators. More...

bool	enableDiffHysteresisThresh
	This field act the same rule as enableDiffHysteresis. More...

bool	enableCommonHysteresisThresh
	This field act the same rule as enableCommonHysteresis. More...

bool	enableInvertHysteresisSign
	Invert the sign of the hysteresis in DC-DC analog comparators. More...

Field Documentation

bool dcdc_loop_control_config_t::enableDiffHysteresis

This feature improves transient supply ripple and efficiency.

bool dcdc_loop_control_config_t::enableCommonHysteresis

This feature improves transient supply ripple and efficiency.

bool dcdc_loop_control_config_t::enableDiffHysteresisThresh

However, if this field is enabled along with the enableDiffHysteresis, the Hysteresis wuold be doubled.

bool dcdc_loop_control_config_t::enableCommonHysteresisThresh

However, if this field is enabled along with the enableCommonHysteresis, the Hysteresis wuold be doubled.

bool dcdc_loop_control_config_t::enableInvertHysteresisSign

struct dcdc_min_power_config_t

Data Fields
bool	enableUseHalfFetForContinuous
	Use half switch FET for the continuous mode. More...

bool	enableUseDoubleFetForContinuous
	Use double switch FET for the continuous mode. More...

bool	enableUseHalfFreqForContinuous
	Set DCDC clock to half frequency for the continuous mode. More...

bool	enableUseHalfFetForPulsed
	Use half switch FET for the Pulsed mode. More...

bool	enableUseDoubleFetForPulsed
	Use double switch FET for the Pulsed mode. More...

bool	enableUseHalfFreqForPulsed
	Set DCDC clock to half frequency for the Pulsed mode. More...

Field Documentation

bool dcdc_min_power_config_t::enableUseHalfFetForContinuous

bool dcdc_min_power_config_t::enableUseDoubleFetForContinuous

bool dcdc_min_power_config_t::enableUseHalfFreqForContinuous

bool dcdc_min_power_config_t::enableUseHalfFetForPulsed

bool dcdc_min_power_config_t::enableUseDoubleFetForPulsed

bool dcdc_min_power_config_t::enableUseHalfFreqForPulsed

struct dcdc_pulsed_integrator_config_t

Data Fields
bool	enableUseUserIntegratorValue
	Enable to use the setting value in userIntegratorValue field. More...

uint32_t	userIntegratorValue
	User defined integrator value. More...

bool	enablePulseRunSpeedup
	Enable pulse run speedup. More...

Field Documentation

bool dcdc_pulsed_integrator_config_t::enableUseUserIntegratorValue

Otherwise, the predefined hardware setting would be applied internally.

uint32_t dcdc_pulsed_integrator_config_t::userIntegratorValue

The available value is 19-bit.

bool dcdc_pulsed_integrator_config_t::enablePulseRunSpeedup

Macro Definition Documentation

#define FSL_DCDC_DRIVER_VERSION (MAKE_VERSION(2, 0, 4))

Version 2.0.4.

Enumeration Type Documentation

enum _dcdc_status_flags_t

Enumerator

kDCDC_LockedOKStatus

Status to indicate DCDC lock.

Read only bit.

kDCDC_PSwitchStatus

Status to indicate PSWITCH signal.

Read only bit.

kDCDC_PSwitchInterruptStatus

PSWITCH edge detection interrupt status.

enum _dcdc_interrupt_enable_t

Enumerator
kDCDC_PSwitchEdgeDetectInterruptEnable	Enable the edge detect interrupt.

enum _dcdc_pswitch_detect_event_t

Enumerator
kDCDC_PSwitchFallingEdgeDetectEnable	Enable falling edge detect.
kDCDC_PSwitchRisingEdgeDetectEnable	Enable rising edge detect.

enum dcdc_work_mode_t

Enumerator
kDCDC_WorkInContinuousMode	DCDC works in continuous mode when SOC is in low power mode.
kDCDC_WorkInPulsedMode	DCDC works in pulsed mode when SOC is in low power mode.

enum dcdc_hysteretic_threshold_offset_value_t

Enumerator
kDCDC_HystereticThresholdOffset0mV	Target voltage value +/- 0mV.
kDCDC_HystereticThresholdOffset25mV	Target voltage value +/- 25mV.
kDCDC_HystereticThresholdOffset50mV	Target voltage value +/- 50mV.
kDCDC_HystereticThresholdOffset75mV	Target voltage value +/- 75mV.

enum dcdc_vbat_divider_t

Enumerator
kDCDC_VBatVoltageDividerOff	The sensor signal is disabled.
kDCDC_VBatVoltageDivider1	VBat.
kDCDC_VBatVoltageDivider2	VBat/2.
kDCDC_VBatVoltageDivider4	VBat/4.

enum dcdc_clock_source_t

Enumerator
kDCDC_ClockAutoSwitch	Automatic clock switch from internal oscillator to external clock.

Function Documentation

void DCDC_Init ( DCDC_Type * base )

Parameters

base	DCDC peripheral base address.

void DCDC_Deinit ( DCDC_Type * base )

Parameters

base	DCDC peripheral base address.

uint32_t DCDC_GetStatusFlags ( DCDC_Type * base )

base DCDC peripheral base address.

Returns: Masks of asserted status flags. See to "_dcdc_status_flags_t".

void DCDC_ClearStatusFlags	(	DCDC_Type *	base,
		uint32_t	mask
	)

base DCDC peripheral base address. mask Mask of status values that would be cleared. See to "_dcdc_status_flags_t".

static void DCDC_EnableInterrupts	(	DCDC_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	DCDC peripheral base address.
mask	Mask of interrupt events that would be enabled. See to "_dcdc_interrupt_enable_t".

static void DCDC_DisableInterrupts	(	DCDC_Type *	base,
		uint32_t	mask
	)

inlinestatic

Parameters

base	DCDC peripheral base address.
mask	Mask of interrupt events that would be disabled. See to "_dcdc_interrupt_enable_t".

void DCDC_SetPSwitchInterruptConfig	(	DCDC_Type *	base,
		uint32_t	mask
	)

There are PSWITCH interrupt events can be triggered by falling edge or rising edge. So user can set the interrupt events that would be triggered with this function. Un-asserted events would be disabled. The interrupt of PSwitch should be enabled as well if to sense the PSWTICH event. By default, no interrupt events would be enabled.

Parameters

base	DCDC peripheral base address.
mask	Mask of interrupt events for PSwtich. See to "_dcdc_pswitch_detect_event_t".

void DCDC_GetDefaultLowPowerConfig ( dcdc_low_power_config_t * config )

The default configuration are set according to responding registers' setting when powered on. They are:

*   config->workModeInVLPRW = kDCDC_WorkInPulsedMode;
*   config->workModeInVLPS = kDCDC_WorkInPulsedMode;
*   config->enableHysteresisVoltageSense = true;
*   config->enableAdjustHystereticValueSense = false;
*   config->enableHystersisComparator = true;
*   config->enableAdjustHystereticValueComparator = false;
*   config->hystereticUpperThresholdValue = kDCDC_HystereticThresholdOffset75mV;
*   config->hystereticLowerThresholdValue = kDCDC_HystereticThresholdOffset0mV;
*   config->enableDiffComparators = false;
* 

Parameters

config Pointer to configuration structure. See to "dcdc_low_power_config_t".

void DCDC_SetLowPowerConfig	(	DCDC_Type *	base,
		const dcdc_low_power_config_t *	config
	)

Parameters

base	DCDC peripheral base address.
config	Pointer to configuration structure. See to "dcdc_low_power_config_t".

void DCDC_GetDefaultLoopControlConfig ( dcdc_loop_control_config_t * config )

The default configuration are set according to responding registers' setting when powered on. They are:

*   config->enableDiffHysteresis = false;
*   config->enableCommonHysteresis = false;
*   config->enableDiffHysteresisThresh = false;
*   config->enableCommonHysteresisThresh = false;
*   config->enableInvertHysteresisSign = false;
* 

Parameters

config Pointer to configuration structure. See to "dcdc_loop_control_config_t".

void DCDC_SetLoopControlConfig	(	DCDC_Type *	base,
		const dcdc_loop_control_config_t *	config
	)

Parameters

base	DCDC peripheral base address.
config	Pointer to configuration structure. See to "dcdc_loop_control_config_t".

static void DCDC_EnableXtalOKDetectionCircuit	(	DCDC_Type *	base,
		bool	enable
	)

inlinestatic

The XTAL OK detection circuit is enabled by default.

Parameters

base	DCDC peripheral base address.
enable	Enable the feature or not.

static void DCDC_EnableOutputRangeComparator	(	DCDC_Type *	base,
		bool	enable
	)

inlinestatic

The output range comparator is enabled by default.

Parameters

base	DCDC peripheral base address.
enable	Enable the feature or not.

static void DCDC_EnableReduceCurrent	(	DCDC_Type *	base,
		bool	enable
	)

inlinestatic

To enable this feature will save approximately 20 µA in RUN mode. This feature is disabled by default.

Parameters

base	DCDC peripheral base address.
enable	Enable the feature or not.

void DCDC_SetClockSource	(	DCDC_Type *	base,
		dcdc_clock_source_t	clockSource
	)

This function is to set the clock source for DCDC. By default, DCDC can switch the clock from internal oscillator to external clock automatically. Once the application choose to use the external clock with function, the internal oscillator would be powered down. However, the internal oscillator could be powered down only when 32MHz crystal oscillator is available.

Parameters

base	DCDC peripheral base address.
clockSource	Clock source for DCDC. See to "dcdc_clock_source_t".

static void DCDC_SetBatteryVoltageDivider	(	DCDC_Type *	base,
		dcdc_vbat_divider_t	divider
	)

inlinestatic

This function controls VBAT voltage divider. The divided VBAT output is input to an ADC channel which allows the battery voltage to be measured.

Parameters

base	DCDC peripheral base address.
divider	Setting divider selection. See to "dcdc_vbat_divider_t"

void DCDC_SetBatteryMonitorValue	(	DCDC_Type *	base,
		uint32_t	battValue
	)

This function is to set the battery monitor value. If the feature of monitoring battery voltage is enabled (with non-zero value set), user should set the battery voltage measured with an 8 mV LSB resolution from the ADC sample channel. It would improve efficiency and minimize ripple.

Parameters

base	DCDC peripheral base address.
battValue	Battery voltage measured with an 8 mV LSB resolution with 10-bit ADC sample. Setting 0x0 would disable feature of monitoring battery voltage.

static void DCDC_DoSoftShutdown ( DCDC_Type * base )

inlinestatic

This function is to shutdown the DCDC module and stop the power supply for chip. In case the chip is powered by DCDC, which means the DCDC is working as Buck/Boost mode, to shutdown the DCDC would cause the chip to reset! Then, the DCDC_REG4_DCDC_SW_SHUTDOWN bit would be cleared automatically during power up sequence. If the DCDC is in bypass mode, which depends on the board's hardware connection, to shutdown the DCDC would not be meaningful.

Parameters

base	DCDC peripheral base address.

static void DCDC_SetUpperLimitDutyCycleBuck	(	DCDC_Type *	base,
		uint32_t	value
	)

inlinestatic

Parameters

base	DCDC peripheral base address.
value	Setting value for limit duty cycle. Available range is 0-127.

static void DCDC_AdjustDutyCycleSwitchingTargetOutput	(	DCDC_Type *	base,
		uint32_t	value
	)

inlinestatic

Adjust value of duty cycle when switching between VDD1P45 and VDD1P8. The unit is 1/32 or 3.125%.

Parameters

base	DCDC peripheral base address.
value	Setting adjust value. The available range is 0-15. The unit is 1/32 or 3.125&.

static void DCDC_LockTargetVoltage ( DCDC_Type * base )

inlinestatic

This function is to lock the setting of target voltage. This function should be called before entering the low power modes to lock the target voltage.

Parameters

base	DCDC peripheral base address.

void DCDC_AdjustTargetVoltage	(	DCDC_Type *	base,
		uint32_t	vdd1p5xBuck,
		uint32_t	vdd1p8
	)

This function is to adjust the target voltage of DCDC output. It would unlock the setting of target voltages, change them and finally wait until the output is stabled.

Parameters

base	DCDC peripheral base address.
vdd1p5xBuck	Target value of VDD1P5X in buck mode, 25 mV each step from 0x00 to 0x0F. 0x00 is for 1.275V.
vdd1p8	Target value of VDD1P8, 25 mV each step in two ranges, from 0x00 to 0x11 and 0x20 to 0x3F. 0x00 is for 1.65V, 0x20 is for 2.8V.

void DCDC_GetDefaultMinPowerDefault ( dcdc_min_power_config_t * config )

The default configuration are set according to responding registers' setting when powered on. They are:

*   config->enableUseHalfFetForContinuous = false;
*   config->enableUseDoubleFetForContinuous = false;
*   config->enableUseHalfFreqForContinuous = false;
*   config->enableUseHalfFetForPulsed = false;
*   config->enableUseDoubleFetForPulsed = false;
*   config->enableUseHalfFreqForPulsed = false;
* 

Parameters

config Pointer to configuration structure. See to "dcdc_min_power_config_t".

void DCDC_SetMinPowerConfig	(	DCDC_Type *	base,
		const dcdc_min_power_config_t *	config
	)

Parameters

base	DCDC peripheral base address.
config	Pointer to configuration structure. See to "dcdc_min_power_config_t".

void DCDC_GetDefaultPulsedIntegratorConfig ( dcdc_pulsed_integrator_config_t * config )

The default configuration are set according to responding registers' setting when powered on. They are:

*   config->enableUseUserIntegratorValue = false;
*   config->userIntegratorValue = 0U;
*   config->enablePulseRunSpeedup = false;
* 

Parameters

config Pointer to configuration structure. See to "dcdc_pulsed_integrator_config_t".

void DCDC_SetPulsedIntegratorConfig	(	DCDC_Type *	base,
		const dcdc_pulsed_integrator_config_t *	config
	)

Parameters

base	DCDC peripheral base address. Pointer to configuration structure. See to "dcdc_pulsed_integrator_config_t".

Overview

Function groups

Initialization and deinitialization

Status

Interrupts

Misc control

Application guideline

Continuous mode

Target voltage adjustment

Pulsed mode

Data Structures

Macros

Enumerations

Initialization and deinitialization

Status

Interrupts

Misc control.

Data Structure Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Data Fields

Field Documentation

Macro Definition Documentation

Enumeration Type Documentation

Function Documentation