Timing Measurement

Measure period, frequency, duty cycle, rise time, fall time, and delay of a signal

Since R2020b

• 

Libraries:
Mixed-Signal Blockset / Utilities

Description

The Timing Measurement block measures the basic timing metrics such as period, frequency, duty cycle, rise time, fall time, and delay of a signal.

Examples

Measure Timing Metrics of Periodic Signal

Measure the period, frequency, rise time, fall time, and duty cycle of a periodic signal. Also measure the delay of the input signal with respect to a reference signal

Open the model time_metrics_measure. The model consists of a Timing Measurement block. A period sine wave of 50e6 Hz is applied at the reference input signal. A variable time delay of 1e-11 s is applied at the test input port. The Timing Measurement block is set to measure the period, frequency, 10%-90% rise time, 90%-10% fall time, duty cycle, and the delay with respect to the test input port.

model = 'time_metrics_measure';
open_system(model)

Run the model for 100 microseconds. The results are displayed on a Display block.

• Period = 0.2 microseconds

• Frequency = 50 MHz

• Rise time = 5.903 nanoseconds

• Fall time = 5.903 nanoseconds

• Duty cycle = 0.5

• Delay = 10 picoseconds

Ports

Input

reference — Input signal

scalar

Input signal whose timing metrics are being measured, specified as a scalar.

Data Types: double

test — Test signal

scalar

Test signal against which the delay of the input signal is measured, specified as a scalar.

Dependencies

To enable this port, select Delay as a measurement option in the Selection tab.

Data Types: double

Output

period — Period of input signal

scalar

Period of the input signal, returned as a scalar.

Data Types: double

frequency — Frequency of input signal

scalar

Frequency of the input signal, returned as a scalar.

Dependencies

To enable this port, select Frequency as a measurement option in the Selection tab.

Data Types: double

rise time — Rise time of input signal

scalar

Rise time of the input signal, returned as a scalar.

Dependencies

To enable this port, select Rise Time as a measurement option in the Selection tab.

Data Types: double

fall time — Fall time of input signal

scalar

Fall time of the input signal, returned as a scalar.

Dependencies

To enable this port, select Fall time as a measurement option in the Selection tab.

Data Types: double

duty cycle — Duty cycle of input signal

scalar

Duty cycle of the input signal, returned as a scalar.

Dependencies

To enable this port, select Duty Cycle as a measurement option in the Selection tab.

Data Types: double

delay — Delay of input signal

scalar

Delay of the input signal, returned as a scalar.

Dependencies

To enable this port, select Delay as a measurement option in the Selection tab.

Data Types: double

Parameters

Selection

Period — Measure period of input signal

on (default) | off

Select to measure the period of the input signal.

Period is defined as the time required to complete one full cycle of a periodic signal, specified in seconds.

Frequency — Measure frequency of input signal

off (default) | on

Select to measure the frequency of the input signal.

Frequency is defined as the number of cycles completed per unit of time by a periodic signal, specified in hertz. It is the inverse of Period.

Rise Time — Measure rise time of input signal

off (default) | on

Select to measure the rise time of the input signal.

Rise time is defined as the time required by the rising edge of the signal to reach from 10% to 90% (or 20% to 80%) of its steady state value, specified in seconds.

Fall Time — Measure fall time of input signal

off (default) | on

Select to measure the fall time of the input signal.

Fall time is defined as the time required by the falling edge of the signal to go from 90% to 10% (or 80% to 20%) of its steady state value, specified in seconds.

Duty Cycle — Measure duty cycle of input signal

off (default) | on

Select to measure the duty cycle of the input signal.

Duty cycle is defined as the ratio of positive pulse width to period, specified as a fraction.

Delay — Measure delay of input signal

off (default) | on

Select to measure the delay of the input signal.

Delay is defined as the time difference between the threshold crossing points between the signal of interest against a test signal, specified in seconds.

Configuration

Use same reference threshold for all measurements — Use the same reference threshold for measuring all timing metrics

on (default) | off

Select to use the same reference threshold for measuring all timing metrics.

Reference threshold (V) — Reference threshold used for measuring timing metrics

0 (default) | scalar

Reference threshold voltage used for measuring all timing metrics, specified as a scalar in volts.

Dependencies

To enable this parameter, select Use same reference threshold for all measurements in the Configuration tab.

Programmatic Use

• Use get_param(gcb,'SameRefThreshold') to view the current value of Reference threshold (V).

• Use set_param(gcb,'SameRefThreshold',value) to set Reference threshold (V) to a specific value.

Period/Frequency

Reference threshold (V) — Reference threshold voltage used to measure period and/or frequency

0 (default) | scalar

Reference threshold voltage used to measure the period and/or the frequency of the signal of interest, specified as a scalar in volts.

Dependencies

To enable this parameter, deselect Use same reference threshold for all measurements in the Configuration tab and select Period and/or Frequency in the Selection tab.

Programmatic Use

• Use get_param(gcb,'PeriodRefThreshold') to view the current value of Reference threshold (V).

• Use set_param(gcb,'PeriodRefThreshold',value) to set Reference threshold (V) to a specific value.

Rise/Fall Time

Input range (V) — Peak-to-peak value of input signal

[-1 1] (default) | 2-element row vector

Peak-to-peak value of the input signal, specified as a 2-element row vector in volts. The first element defines the notch value of the input signal and the second element defines the peak value. Input range (V) is used to calculate the upper and lower threshold levels to calculate the rise/fall times.

Dependencies

To enable this parameter, select Rise Time and/or Fall Time in the Selection tab.

Programmatic Use

• Use get_param(gcb,'Range') to view the current value of Reference threshold (V).

• Use set_param(gcb,'Range',value) to set Reference threshold (V) to a specific value.

Type — Input threshold levels to measure rise/fall times

80%/20% (default) | 90%/10%

Determines the input threshold levels to measure the rise/fall times, specified as either 80%/20% or 90%/10%.

Dependencies

To enable this parameter, select Rise Time and/or Fall Time in the Selection tab.

Programmatic Use

• Use get_param(gcb,'MeasurementType') to view the current value of Reference threshold (V).

• Use set_param(gcb,'MeasurementType',value) to set Reference threshold (V) to a specific value.

Duty Cycle

Reference threshold (V) — Reference threshold voltage used to measure duty cycle

0 (default) | scalar

Reference threshold voltage used to measure the duty cycle of the signal of interest, specified as a scalar in volts.

Dependencies

To enable this parameter, deselect Use same reference threshold for all measurements in the Configuration tab and select Duty Cycle in the Selection tab.

Programmatic Use

• Use get_param(gcb,'DcRefThreshold') to view the current value of Reference threshold (V).

• Use set_param(gcb,'DcRefThreshold',value) to set Reference threshold (V) to a specific value.

Delay

Reference threshold (V) — Threshold voltage level in signal of interest used to measure delay

0 (default) | scalar

Threshold voltage level in reference signal of interest whose delay is being measured, specified as a scalar in volts.

Dependencies

To enable this parameter, deselect Use same reference threshold for all measurements in the Configuration tab and select Delay in the Selection tab.

Programmatic Use

• Use get_param(gcb,'DelayRefThreshold') to view the current value of Reference threshold (V).

• Use set_param(gcb,'DelayRefThreshold',value) to set Reference threshold (V) to a specific value.

Test threshold (V) — Threshold voltage level in test signal used to measure delay

0 (default) | scalar

Threshold voltage level in test signal against which the delay of the reference signal is being measured, specified as a scalar in volts.

Dependencies

To enable this parameter, deselect Use same reference threshold for all measurements in the Configuration tab and select Delay in the Selection tab.

Programmatic Use

• Use get_param(gcb,'DelayTstThreshold') to view the current value of Reference threshold (V).

• Use set_param(gcb,'DelayTstThreshold',value) to set Reference threshold (V) to a specific value.

Version History

Introduced in R2020b