GPIO amplifier

Amplifier switched by an enable GPIO, with an optional supply. More...

Data Structures
struct	pbl_audio_amp_gpio
	GPIO amplifier. More...

Macros
#define	PBL_AUDIO_AMP_GPIO_DEFINE(sym, _name, _enable, _supply, ...)
	Define a GPIO amplifier.

Detailed Description

Amplifier switched by an enable GPIO, with an optional supply.

Some class-D amplifiers select their mode from the number of pulses on the enable line before it stays active: the driver sends mode_pulses pulses of pulse_us high and low first.

PBL_AUDIO_AMP_GPIO_DEFINE(s_amp, "amp", PBL_GPIO(SF32LB_GPIO1, 0, 0), nullptr,
                          .mode_pulses = 1, .pulse_us = 200, .settle_us = 2000);

---

Data Structure Documentation

pbl_audio_amp_gpio

struct pbl_audio_amp_gpio

GPIO amplifier.

Data Fields
struct pbl_audio_amp	amp	Amplifier.
struct pbl_gpio	enable	Enable line.
uint8_t	mode_pulses	Mode pulses sent before enabling.
uint16_t	pulse_us	Length of each half of a mode pulse, in microseconds.
uint16_t	settle_us	Time to settle once the line is driven inactive, in microseconds.
const struct pbl_regulator *	supply	Supply, or NULL.

Macro Definition Documentation

PBL_AUDIO_AMP_GPIO_DEFINE

#define PBL_AUDIO_AMP_GPIO_DEFINE	(		sym,
			_name,
			_enable,
			_supply,
			...
	)

Value:

  PBL_DEVICE_STATE_DEFINE(sym);                                                          \
  static const struct pbl_audio_amp_gpio sym = {                                         \
    .amp =                                                                               \
        {                                                                                \
          .dev = PBL_DEVICE_INIT(sym, _name, pbl_audio_amp_gpio_init, nullptr, nullptr), \
          .ops = &pbl_audio_amp_gpio_ops,                                                \
        },                                                                               \
    .enable = _enable,                                                                   \
    .supply = (_supply),                                                                 \
    __VA_ARGS__                                                                          \
  };                                                                                     \
  PBL_DEVICE_REGISTER(sym, &sym.amp.dev)

Define a GPIO amplifier.

Parameters

sym	Symbol of the amplifier.
_name	Device name.
_enable	Enable line, from PBL_GPIO().
_supply	Supply, or NULL.
...	Further fields: mode_pulses, pulse_us, settle_us.