TI LDC1614 inductance-to-digital field-sensing codec (DETWS_ENABLE_LDC1614). More...

#include <stddef.h>
#include <stdint.h>

Macros
#define	LDC1614_REG_DATA_CH0_MSB 0x00

#define	LDC1614_REG_DATA_CH0_LSB 0x01

#define	LDC1614_REG_RCOUNT_CH0 0x08

#define	LDC1614_REG_SETTLECOUNT_CH0 0x10

#define	LDC1614_REG_CLOCK_DIVIDERS_CH0 0x14

#define	LDC1614_REG_STATUS 0x18

#define	LDC1614_REG_ERROR_CONFIG 0x19

#define	LDC1614_REG_CONFIG 0x1A

#define	LDC1614_REG_MUX_CONFIG 0x1B

#define	LDC1614_REG_DRIVE_CURRENT_CH0 0x1E

#define	LDC1614_REG_MANUFACTURER_ID 0x7E

#define	LDC1614_REG_DEVICE_ID 0x7F

#define	LDC1614_MANUFACTURER_ID 0x5449
	"TI".

#define	LDC1614_DEVICE_ID 0x3055
	LDC1614 / LDC1612.

#define	LDC1614_CONFIG_MAX 21
	Largest config sequence in bytes: 7 register writes * 3 bytes (reg, msb, lsb).

Functions
uint32_t	ldc1614_data (uint16_t msb_reg, uint16_t lsb_reg)
	Combine a DATA MSB register (low 12 bits) and DATA LSB register into the 28-bit result.

uint8_t	ldc1614_error (uint16_t msb_reg)
	The 4 error flags from the top of a DATA MSB register (bits 15:12).

uint64_t	ldc1614_sensor_freq_hz (uint32_t data28, uint32_t fref_hz)
	Sensor frequency in Hz for a 28-bit result against a reference clock: data / 2^28 * fref.

size_t	ldc1614_build_config (uint8_t *buf, size_t cap, uint16_t rcount, uint16_t settlecount)
	Emit a single-channel (CH0) continuous-conversion bring-up as `(reg, val_msb, val_lsb)` triples.

bool	ldc1614_begin (uint8_t addr, uint16_t rcount, uint16_t settlecount)
	Verify the device id and apply the CH0 config at `addr`.

bool	ldc1614_read_ch0 (uint32_t *out)
	Read channel 0's 28-bit conversion result into `out`.

Detailed Description

TI LDC1614 inductance-to-digital field-sensing codec (DETWS_ENABLE_LDC1614).

The LDC1614 measures the resonant frequency of an external LC tank driven by a coil; a nearby conductor changes the coil's effective inductance (eddy currents), moving that frequency - so the 28-bit conversion result tracks metal proximity, displacement, and EM-field perturbation without contact. It shares TI's FDC/LDC register architecture: each channel's result is a DATA MSB register (top 4 bits error flags, low 12 bits data MSB) plus a DATA LSB register, combining into 28 bits, with f_sensor = data / 2^28 * f_ref and L = 1 / (C * (2*pi*f)^2) derived by the app from the tank C.

This codec is pure and host-tested: ldc1614_data combines the register pair, ldc1614_error pulls the flags, ldc1614_sensor_freq_hz scales to frequency, and ldc1614_build_config emits a single-channel bring-up. On an ESP32 the binding replays that config and reads the channel over I2C; only that touches hardware. Bridge the readings northbound like any sensor.

Definition in file ldc1614.h.

Macro Definition Documentation

◆ LDC1614_REG_DATA_CH0_MSB

#define LDC1614_REG_DATA_CH0_MSB 0x00

Definition at line 28 of file ldc1614.h.

◆ LDC1614_REG_DATA_CH0_LSB

#define LDC1614_REG_DATA_CH0_LSB 0x01

Definition at line 29 of file ldc1614.h.

◆ LDC1614_REG_RCOUNT_CH0

#define LDC1614_REG_RCOUNT_CH0 0x08

Definition at line 30 of file ldc1614.h.

◆ LDC1614_REG_SETTLECOUNT_CH0

#define LDC1614_REG_SETTLECOUNT_CH0 0x10

Definition at line 31 of file ldc1614.h.

◆ LDC1614_REG_CLOCK_DIVIDERS_CH0

#define LDC1614_REG_CLOCK_DIVIDERS_CH0 0x14

Definition at line 32 of file ldc1614.h.

◆ LDC1614_REG_STATUS

#define LDC1614_REG_STATUS 0x18

Definition at line 33 of file ldc1614.h.

◆ LDC1614_REG_ERROR_CONFIG

#define LDC1614_REG_ERROR_CONFIG 0x19

Definition at line 34 of file ldc1614.h.

◆ LDC1614_REG_CONFIG

#define LDC1614_REG_CONFIG 0x1A

Definition at line 35 of file ldc1614.h.

◆ LDC1614_REG_MUX_CONFIG

#define LDC1614_REG_MUX_CONFIG 0x1B

Definition at line 36 of file ldc1614.h.

◆ LDC1614_REG_DRIVE_CURRENT_CH0

#define LDC1614_REG_DRIVE_CURRENT_CH0 0x1E

Definition at line 37 of file ldc1614.h.

◆ LDC1614_REG_MANUFACTURER_ID

#define LDC1614_REG_MANUFACTURER_ID 0x7E

Definition at line 38 of file ldc1614.h.

◆ LDC1614_REG_DEVICE_ID

#define LDC1614_REG_DEVICE_ID 0x7F

Definition at line 39 of file ldc1614.h.

◆ LDC1614_MANUFACTURER_ID

#define LDC1614_MANUFACTURER_ID 0x5449

"TI".

Definition at line 41 of file ldc1614.h.

◆ LDC1614_DEVICE_ID

#define LDC1614_DEVICE_ID 0x3055

LDC1614 / LDC1612.

Definition at line 42 of file ldc1614.h.

◆ LDC1614_CONFIG_MAX

#define LDC1614_CONFIG_MAX 21

Largest config sequence in bytes: 7 register writes * 3 bytes (reg, msb, lsb).

Definition at line 45 of file ldc1614.h.

Function Documentation

◆ ldc1614_data()

uint32_t ldc1614_data	(	uint16_t	msb_reg,
		uint16_t	lsb_reg
	)

Combine a DATA MSB register (low 12 bits) and DATA LSB register into the 28-bit result.

◆ ldc1614_error()

uint8_t ldc1614_error ( uint16_t msb_reg )

The 4 error flags from the top of a DATA MSB register (bits 15:12).

◆ ldc1614_sensor_freq_hz()

uint64_t ldc1614_sensor_freq_hz	(	uint32_t	data28,
		uint32_t	fref_hz
	)

Sensor frequency in Hz for a 28-bit result against a reference clock: data / 2^28 * fref.

◆ ldc1614_build_config()

size_t ldc1614_build_config	(	uint8_t *	buf,
		size_t	cap,
		uint16_t	rcount,
		uint16_t	settlecount
	)

Emit a single-channel (CH0) continuous-conversion bring-up as (reg, val_msb, val_lsb) triples.

Writes RCOUNT, SETTLECOUNT, CLOCK_DIVIDERS, DRIVE_CURRENT, ERROR_CONFIG, MUX_CONFIG, then CONFIG last (CONFIG starts the conversion). Replay each triple as a 16-bit I2C register write.

Returns: bytes written (7 * 3 = 21), or 0 if cap < LDC1614_CONFIG_MAX.

◆ ldc1614_begin()

bool ldc1614_begin	(	uint8_t	addr,
		uint16_t	rcount,
		uint16_t	settlecount
	)

Verify the device id and apply the CH0 config at addr.

Returns: true if present + acked.

◆ ldc1614_read_ch0()

bool ldc1614_read_ch0 ( uint32_t * out )

Read channel 0's 28-bit conversion result into out.

Returns: false on I2C error.

Macros

Functions