7.3.5 Reference Clock

Optimum LDC1312/LDC1314 performance requires a clean reference clock. This reference frequency is equivalent to the reference voltage of an Analog-to-Digital converter. The LDC1312/LDC1314 provide an internal reference oscillator with a typical frequency of 43 MHz. This internal oscillator has good stability, with a typical temperature coefficient of -13 ppm/°C. For applications requiring higher resolution or improved performance across temperature, an external reference frequency can be applied to the CLKIN input.

The LDC1312/LDC1314 provides digital dividers for the ƒ_CLK and the sensor inputs to adjust the effective frequency measured by the LDC core. The dividers provide flexibility in system design, so that the full range of sensor frequencies can be supported with a wide range of ƒ_CLK. Each channel has a dedicated divider configuration. Higher reference frequencies provide a higher sample rate for a given resolution.

Refer to Reference Clock for details on clocking requirements, configuration, and divider setup.