9.3.6 Clock

The ADS131E08S provides two different device clocking methods: internal and external. Internal clocking using the internal oscillator is ideally-suited for non-synchronized, low-power systems. The internal oscillator is trimmed for accuracy at room temperature. The accuracy of the internal oscillator varies over the specified temperature range; see the Electrical Characteristics table for details. External clocking is recommended when synchronizing multiple ADS131E08S devices or when synchronizing to an external event because the internal oscillator clock performance can vary over temperature. Clock selection is controlled by the CLKSEL pin and the CLK_EN register bit. Provide the external clock any time after the analog and digital supplies are present.

The CLKSEL pin selects either the internal oscillator or external clock. The CLK_EN bit in the CONFIG1 register enables and disables the oscillator clock to be output on the CLK pin. A truth table for the CLKSEL pin and the CLK_EN bit is shown in Table 4. The CLK_EN bit is useful when multiple devices are used in a daisy-chain configuration. During power-down, the external clock is recommended to be shut down to save power.