SNAS854 February 2023 TDC1000-Q1
PRODUCTION DATA
The duration of the common-mode settling time is defined by the VCOM capacitor. With a 10-nF VCOM capacitor, the common-mode reference requires 16 µs to settle. On the other hand, the duration of the common-mode settling window is defined as 128 × T0, where the time unit T0 is determined by the external clock frequency and the value of the CLOCKIN_DIV bit, as explained in the Timing Control and Frequency Scaling (CLKIN) section.
A frequency of 8 MHz will result in a settling window of 128 × 1 / 8 MHz, which equals to 16 µs. Increasing the value of the VCOM capacitor will increase the common-mode settling time, but for the same 8-MHz frequency, the duration of the common-mode settling window will remain at 16 µs. In such situation, the common-mode reference will take multiple TOF cycles to reach the final value when starting from zero initial conditions.