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What is positive and negative voltage regulator?
A fixed voltage regulator produces a fixed DC output voltage, which is either positive or negative. In other words, some fixed voltage regulators produce positive fixed DC voltage values, while others produce negative fixed DC voltage values.
What does a positive voltage regulator do?
The 78xx line are positive voltage regulators: they produce a voltage that is positive relative to a common ground. There is a related line of 79xx devices which are complementary negative voltage regulators.
Is an example of fixed positive voltage regulator?
Examples:- 7805, 7806, 7809 etc. A negative fixed voltage regulator is same as the positive fixed voltage regulator in design, construction & operation. These IC’s are designed to provide a negative output voltage. Example:- 7905, 7906 and all those IC’s in the 79XX series.
Is voltage regulation always positive?
Voltage regulation is defined as the change in terminal voltage expressed as a fraction of full load rated voltage when the load at a given power factor is removed while keeping the speed and field current constant. Voltage regulation is always positive for lagging power factor load and Ef is always increasing.
Can a positive linear regulator generate a negative voltage?
Figure 1. A positive linear regulator for generating a negative voltage will not usually work due to the direction of current flow. A second negative about such a use case for a positive linear regulator is that the I/O pins of the linear regulator device, such as an enable pin, will be referenced to –5 V.
What is the support voltage for negative voltages?
For the necessary negative voltage of –3.3 V, an available support voltage of –5 V may be utilized. This voltage rail may come from a transformer-based power supply. Typically, such voltages are not regulated very accurately.
How does a resistive divider regulate the output voltage?
The circuit will use the resistive divider to regulate the output voltage based on the –5 V rail and not based on the 0 V rail, system ground. This causes disturbances and noise on the –5 V rail to couple directly onto the generated –3.3 V rail.