IDAC - Current DAC

Description

Current Digital-to-Analog Converter (IDAC) Peripheral API.

IDAC can source or sink a configurable constant current, which can be output on, or sinked from pin or ADC. Current is configurable with several ranges of various step sizes. IDAC can be used with PRS and can operate down to EM3.

The following steps are necessary for basic operation:

Clock enable:

/* IDAC is a HFPERCLK peripheral */
CMU_ClockEnable(cmuClock_HFPER, true);
CMU_ClockEnable(cmuClock_IDAC0, true);

Initialize peripheral with default settings and modify selected fields, such as output select:

/* Initialize with default settings. Change output to ADC. */
IDAC_Init_TypeDef init = IDAC_INIT_DEFAULT;
init.outMode = idacOutputADC;
IDAC_Init(IDAC0, &init);

Set output:

/* Set 50nA step and enable output */
IDAC_StepSet(IDAC0, 0);
IDAC_OutEnable(IDAC0, true);

Data Structures

struct  IDAC_Init_TypeDef
 IDAC initialization structure, common for both channels.
 

Functions

void IDAC_Init (IDAC_TypeDef *idac, const IDAC_Init_TypeDef *init)
 Initialize IDAC.
 
void IDAC_Enable (IDAC_TypeDef *idac, bool enable)
 Enable/disable IDAC.
 
void IDAC_Reset (IDAC_TypeDef *idac)
 Reset IDAC to the same state that it was in after a hardware reset.
 
void IDAC_MinimalOutputTransitionMode (IDAC_TypeDef *idac, bool enable)
 Enable/disable Minimal Output Transition mode.
 
void IDAC_RangeSet (IDAC_TypeDef *idac, const IDAC_Range_TypeDef range)
 Set the current range of the IDAC output.
 
void IDAC_StepSet (IDAC_TypeDef *idac, const uint32_t step)
 Set the current step of the IDAC output.
 
void IDAC_OutEnable (IDAC_TypeDef *idac, bool enable)
 Enable/disable the IDAC OUT pin.
 

Macros

#define IDAC_INIT_DEFAULT
 Default configuration for IDAC initialization structure.
 

Enumerations

enum  IDAC_OutMode_TypeDef {
  idacOutputPin = IDAC_CTRL_OUTMODE_PIN,
  idacOutputADC = IDAC_CTRL_OUTMODE_ADC
}
 Output mode.
 
enum  IDAC_PRSSEL_TypeDef {
  idacPRSSELCh0 = IDAC_CTRL_PRSSEL_PRSCH0,
  idacPRSSELCh1 = IDAC_CTRL_PRSSEL_PRSCH1,
  idacPRSSELCh2 = IDAC_CTRL_PRSSEL_PRSCH2,
  idacPRSSELCh3 = IDAC_CTRL_PRSSEL_PRSCH3
}
 Selects which Peripheral Reflex System (PRS) signal to use when PRS is set to control IDAC output.
 
enum  IDAC_Range_TypeDef {
  idacCurrentRange0 = IDAC_CURPROG_RANGESEL_RANGE0,
  idacCurrentRange1 = IDAC_CURPROG_RANGESEL_RANGE1,
  idacCurrentRange2 = IDAC_CURPROG_RANGESEL_RANGE2,
  idacCurrentRange3 = IDAC_CURPROG_RANGESEL_RANGE3
}
 Selects which current range to use.
 

Function Documentation

◆ IDAC_Init()

void IDAC_Init ( IDAC_TypeDef *  idac,
const IDAC_Init_TypeDef *  init 
)

Initialize IDAC.

Initializes IDAC according to the initialization structure parameter and sets the default calibration value stored in the DEVINFO structure.

Note
This function will disable IDAC prior to configuration.
Parameters
[in]idacA pointer to the IDAC peripheral register block.
[in]initA pointer to the IDAC initialization structure.

◆ IDAC_Enable()

void IDAC_Enable ( IDAC_TypeDef *  idac,
bool  enable 
)

Enable/disable IDAC.

Parameters
[in]idacA pointer to the IDAC peripheral register block.
[in]enableTrue to enable IDAC, false to disable.

◆ IDAC_Reset()

void IDAC_Reset ( IDAC_TypeDef *  idac)

Reset IDAC to the same state that it was in after a hardware reset.

Parameters
[in]idacA pointer to the IDAC peripheral register block.

◆ IDAC_MinimalOutputTransitionMode()

void IDAC_MinimalOutputTransitionMode ( IDAC_TypeDef *  idac,
bool  enable 
)

Enable/disable Minimal Output Transition mode.

Parameters
[in]idacA pointer to the IDAC peripheral register block.
[in]enableTrue to enable Minimal Output Transition mode, false to disable.

◆ IDAC_RangeSet()

void IDAC_RangeSet ( IDAC_TypeDef *  idac,
const IDAC_Range_TypeDef  range 
)

Set the current range of the IDAC output.

This function sets the current range of the IDAC output. The function also updates the IDAC calibration register (IDAC_CAL) with the default calibration value from DEVINFO (factory calibration) corresponding to the specified range.

Parameters
[in]idacA pointer to the IDAC peripheral register block.
[in]rangeThe current range value.

◆ IDAC_StepSet()

void IDAC_StepSet ( IDAC_TypeDef *  idac,
const uint32_t  step 
)

Set the current step of the IDAC output.

Parameters
[in]idacA pointer to the IDAC peripheral register block.
[in]stepA step value for the IDAC output. A valid range is 0-31.

◆ IDAC_OutEnable()

void IDAC_OutEnable ( IDAC_TypeDef *  idac,
bool  enable 
)

Enable/disable the IDAC OUT pin.

Parameters
[in]idacA pointer to the IDAC peripheral register block.
[in]enableTrue to enable the IDAC OUT pin, false to disable.

Macro Definition Documentation

◆ IDAC_INIT_DEFAULT

#define IDAC_INIT_DEFAULT
Value:
{ \
false, \
idacOutputPin, \
false, \
idacPRSSELCh0, \
false \
}

Default configuration for IDAC initialization structure.

Enumeration Type Documentation

◆ IDAC_OutMode_TypeDef

enum IDAC_OutMode_TypeDef

Output mode.

Enumerator
idacOutputPin 

Output to IDAC OUT pin.

idacOutputADC 

Output to ADC.

◆ IDAC_PRSSEL_TypeDef

enum IDAC_PRSSEL_TypeDef

Selects which Peripheral Reflex System (PRS) signal to use when PRS is set to control IDAC output.

Enumerator
idacPRSSELCh0 

PRS channel 0.

idacPRSSELCh1 

PRS channel 1.

idacPRSSELCh2 

PRS channel 2.

idacPRSSELCh3 

PRS channel 3.

◆ IDAC_Range_TypeDef

enum IDAC_Range_TypeDef

Selects which current range to use.

Enumerator
idacCurrentRange0 

current range 0.

idacCurrentRange1 

current range 1.

idacCurrentRange2 

current range 2.

idacCurrentRange3 

current range 3.