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Which is a disadvantage of switched mode power supplies compared with series regulated supplies?
Switched mode supplies are more expensive to implement than series regulated supplies. It is more difficult to prevent high frequency electrical interference in switched mode supplies. Over voltage protection is not possible in switched mode power supplies.
Which answer from the following list is a major advantage of switched mode power supply?
Switched mode supplies create smaller amplitude ripple waveforms than series regulators. Switched mode supplies dissipate less power in the control element than series regulators. Switched mode supplies provide better regulation at low power than series regulators.
What is the main disadvantage of SMPS?
The disadvantages of SMPS are as under : SMPS has higher output ripple and its regulation in worse. SMPS is a source of both electromagnetic and radio interference due to the high-frequency switching. Control of radio frequency noise requires the use of filters on both input and output of SMPS.
Which answer from the following list is a major advantage of switched mode?
Why do I need a higher switching frequency for SMPS?
If you increase the PWM signal edge rate, the MOSFET can be fully cycled and it will conduct less in the OFF state. This actually reduces power loss, even when the switching frequency is set to a higher value. The combination of a higher PWM frequency and faster PWM edge rate allows smaller components to be used in the SMPS circuit.
Is the edge rate important in a SMPS circuit?
In reality, with power MOSFETs used in SMPS circuits, the edge rate is an important determinant of the heating losses in the SMPS circuit. No circuit element is ideal, but we tend to treat them as such when it is not appropriate.
What causes voltage spikes in a SMPS circuit?
The parasitic capacitance also contributes to voltage/current spikes in the SMPS circuit, but this does not dominate until you are working at kV levels. This particular voltage spike, due to parasitic inductance, occupies circuit loops in your SMPS layout, which can stress components to the point of failure.
What causes a PWM to fail in a SMPS?
A fast rising edge in the PWM signal with an ON current of a few amps can induce a spike of several volts. Over time, this stresses components and leads to failure of the SMPS.