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  2. Pulse-width modulation - Wikipedia

    en.wikipedia.org/wiki/Pulse-width_modulation

    The PWM switching frequency can vary greatly depending on load and application. For example, switching only has to be done several times a minute in an electric stove; 100 or 120 Hz (double of the utility frequency ) in a lamp dimmer ; between a few kilohertz (kHz) and tens of kHz for a motor drive; and well into the tens or hundreds of kHz in ...

  3. Servo control - Wikipedia

    en.wikipedia.org/wiki/Servo_control

    Servo and receiver connections A diagram showing typical PWM timing for a servomotor. Servo control is a method of controlling many types of RC/hobbyist servos by sending the servo a PWM (pulse-width modulation) signal, a series of repeating pulses of variable width where either the width of the pulse (most common modern hobby servos) or the duty cycle of a pulse train (less common today ...

  4. Position weight matrix - Wikipedia

    en.wikipedia.org/wiki/Position_weight_matrix

    A PWM has one row for each symbol of the alphabet (4 rows for nucleotides in DNA sequences or 20 rows for amino acids in protein sequences) and one column for each position in the pattern. In the first step in constructing a PWM, a basic position frequency matrix (PFM) is created by counting the occurrences of each nucleotide at each position.

  5. Random pulse-width modulation - Wikipedia

    en.wikipedia.org/wiki/Random_pulse-width_modulation

    In RPWM, one of the switching parameters of the PWM signal, such as switching frequency, pulse position and duty cycle are varied randomly in order to spread the energy of the PWM signal. Hence, depending on the parameter which is made random, RPWM can be classified as random frequency modulation (RFM), random pulse-position modulation (RPPM ...

  6. Duty cycle - Wikipedia

    en.wikipedia.org/wiki/Duty_cycle

    Pulse-width modulation (PWM) is used in a variety of electronic situations, such as power delivery and voltage regulation. In electronic music, music synthesizers vary the duty cycle of their audio-frequency oscillators to obtain a subtle effect on the tone colors. This technique is known as pulse-width modulation.

  7. Space vector modulation - Wikipedia

    en.wikipedia.org/wiki/Space_vector_modulation

    Space vector modulation (SVM) is an algorithm for the control of pulse-width modulation (PWM), invented by Gerhard Pfaff, Alois Weschta, and Albert Wick in 1982. [1] [2] It is used for the creation of alternating current (AC) waveforms; most commonly to drive 3 phase AC powered motors at varying speeds from DC using multiple class-D amplifiers.

  8. Delta-sigma modulation - Wikipedia

    en.wikipedia.org/wiki/Delta-sigma_modulation

    Delta-sigma (ΔΣ; or sigma-delta, ΣΔ) modulation is an oversampling method for encoding signals into low bit depth digital signals at a very high sample-frequency as part of the process of delta-sigma analog-to-digital converters (ADCs) and digital-to-analog converters (DACs).

  9. Pulse-density modulation - Wikipedia

    en.wikipedia.org/wiki/Pulse-density_modulation

    Pulse-width modulation (PWM) is a special case of PDM where the switching frequency is fixed and all the pulses corresponding to one sample are contiguous in the digital signal. The method for demodulation to an analogue signal remains the same, but the representation of a 50% signal with a resolution of 8-bits, a PWM waveform will turn on for ...