This calculator estimates settling time for a multiplexer by calculating the slower of the two time constants for a cascaded RC network, then computing how many of that time constant must pass before the system will settle to within 1%, 0.1%, 0.01% and 0.001% of its final value.

The calculator also estimates the maximum sampling rate possible for a classic A/D converter with S/H input. The sampling rate is estimated as 1/sqrt( (t_settle+t_transition)² + t_PGA²). This number should be less than the sum of t_ACQ+t_CONV, otherwise the maximum sampling frequency will be limited by the latter. The maximum sampling frequency estimate is shown in megasamples/second to the right of the settling time number.

To use the calculator, enter the multiplexer parameters in R_ON, C_S and C_D and the application parameters in R_SOURCE, R_LOAD and C_LOAD. Tabbing from one field to the other updates the tabular display at right, or click "Calculate".

No special issues are known to exist with this calculator at this time.

For further troubleshooting information, please visit our Interactive Tools troubleshooting page.

Multichannel Applications, (pdf, 607,710 bytes)