PWM
Generates an ideal pulse-width modulated signal according to the input signal well.
Description
The PWM unit generates an ideal pulse width modulated signal.
Pulse Width Modulation (PWM) is a method of encoding an analogue signal by usage of rectangular pulses. The principle of PWM is to change the pulse width at a constant pulse frequency. The ratio of pulse width to period is called the * duty cycle*. The relationship between the modulated signal and duty cycle is described as follows:
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where and are the upper and lower limits of the output signal, respectively.
For the PWM block, the duty cycle lies in the range [0,1]. The ideal PWM signal is proportional to the duty cycle D.
Ports
Parameters
Period - pulse period
1 (by default) | real scalar | vector | matrix
The time between rising edges of successive pulses of the output signal. A small value corresponds to a high frequency pulse.
Block parameters |
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Values |
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* By default* |
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Disallow zero duty cycle - avoid algebraic loops
off (false) (by default) | on (true)
Enable this parameter to break algebraic loops containing a PWM block.
Enabling this parameter causes the signal value to become 0 or lower, causing an input signal error.
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Block parameter |
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Values |
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By default |
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Data types: Bool.
Sample Time - interval between calculation steps
0.1 (by default) | scalar
Specify the interval between calculation steps as a non-negative number.
A value of -1 for the Sample Time parameters causes an error.
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