Advantages and Disadvantages
Types of Power Supply
Trouble Shooting
Functions
General Knowledge
100
Simplicity, low noise/low EMI, one output and V out always less the V in.
What is Linear Advantages
100
The simplest of All power supplies.
What is a Buck Power supply?
100
Forward current is always flowing through the inductor the same way.
What makes a Power supply a forward-mode design.
100
Serves as a gate for replenishing the energy lost to the load during its off-time.
What is the function of power switches?
100
Protects the load from over voltage.
What is a Crowbar circuit?
200
Can only be a step-down regulator, only one output, and lower efficiency typically 30 to 60%.
What is Linear disadvantages.
200
Output voltage is higher than the input voltage.
What is a Boost Power supply?
200
Duty cycle is 0-50% and inductor voltage is allowed to rise to the output.
What makes a power supply a flyback-mode?
200
Converts the bipolar waveform into a a unipolar pulse train, to change polarity-reverse rectifiers polarity.
What is the function of output rectifiers?
200
Prevents excessive input currents at low line voltage, maximum and total current limiters.
What is a Under Voltage Lockout?
300
Higher Efficiency-typically 68-90% reduces heatsink, additional outputs, smaller size, lower cost for ABOVE 10 watts.
What is a Switching power supply Advantages?
300
This is an inverting power supply.
What is a Buck-Boost power supply?
300
Input filter should have low impedance to ground for high frequency shunting.
What is a EMI filter?
300
Provides surge capability to the load and also smooths any ripple present in the output.
What is function of output filters?
300
Allows the output pulse width to gradually increase when power is first applied.
What is a Soft start?
400
More complicated, considerable RF noise on outputs and input-compensated for with filtering, transient response time slower-compensated for by increasing the size or output capacitor.
What is Switching Power Supply Dis Advantages?
400
V in will be more than V out and same polarity.
What is a Buck power supply?
400
Input filter will be a larger capacitor and are surge capacitors that supply surge current to input when switches close.
What is Bulk input filter?
400
The purpose is to develop a voltage that is proportional to the output load current.
What is function of Current sense elements?
400
Where two power switches share the switching function, can be step up or step down.
What is a Push Pull Supply?
500
High ripple paths have minimum length, lots of copper, and very close proximity.
What is Switching Power Supply Disadvantages?
500
The inductor voltage is allowed to rise to the output voltage, more than one output is possible on one supply, can be positive or negative, and step up or step down.
What is a Flyback power supply?
500
Performs a voltage step-up/down function.
What is a transformer in switching power supply?
500
Is a resistor divider across the MOST important output, which reduces rated output voltage to the same voltage as the reference voltage on the input to the voltage error amplifier.
What is function of Voltage feedback elements?
500
Has only one primary winding which is connected between a pull-up/pull-down arrangement of power switches.
What is a half-bridge?
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