7.3.4 Reference Clock

Optimum LDC1612/LDC1614 performance requires a clean reference clock. This reference frequency is equivalent to the reference voltage of an Analog-to-Digital converter. The LDC1612/LDC1614 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 LDC1612/LDC1614 provide digital dividers for the ƒ_CLK and the sensor inputs to adjust the effective frequency measured by the LDC core. For most systems, the maximum permitted reference frequency provides the best performance. 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.

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