A pulse modulator is a device used within an electronic circuit to alter or maintain the amount of power being provided to the device the circuit is powering. If the device has a specific power tolerance threshold that must be maintained in order to protect the circuitry components, a pulse modulator is often the source of modulation for the voltage or power signal supplied to the device. The pulse modulator works to ensure that the accuracy or consistency of the device is maintained.
The modulation of the power supply is done by the pulse modulator when the modulator acts as a control switch. Here, the modulator switches between on and off positions to only allow a specific amount of signal to reach the circuit. If necessary, it will cut the signal to modulate the power.
For instance, the amount of voltage delivered to the circuitry inside an electric stove determines the amount of heat the stove provides. The voltage entering the circuit is dependent on the temperature the user sets as the desired heat, and thus must be modulated to be maintained. The pulse modulator acts as the switch that delivers that specific amount of voltage so the electric stove does not simply heat to its full capacity and become dangerously hot, or simply turn on and stay on for the duration of the cooking time. In order to maintain the desired heat level, the pulse modulator controls the amount of power signal being delivered to the heating element.
Another example of the necessity for pulse modulation is the power supply used in a desktop computer tower. Since different voltages are needed throughout different components of the computer’s circuitry, the power supply must be equipped with a pulse modulator. The modulator is able to switch the amount of voltage to each component to ensure that a component that runs on 5 volts does not receive 12.
Modulators are also utilized in the pulse width modulation of a broadcast frequency signal, mainly for telecommunications or signal deliverance to a wider range. The modulator is placed in the circuit directly before the outgoing signal transmitter and used to modulate the amount of power delivered to the transmitter. This modulation is used to make the signal reach a wider bandwidth by increasing the amount of power that drives the transmitter, making the signal stronger.