A Linear Voltage Regulator ensures the output voltage from the circuit is maintained at a specific voltage.
The device acts as a variable resistor, continuously adjusting to maintain a constant output voltage. The regulated voltage must be lower than the input voltage. Simple voltage regulator contains a Zener Diode and a resistor but more complicated versions include elements like a voltage reference and error amplifiers.
A more specific type of regulator are Low Dropout Voltage Regulators (LDO) which can regulate voltage even when the power supply voltage is very close to the supply voltage.
How to choose linear voltage regulator ICs?
The primary feature in choosing a regulator is usually the Output voltage as the main purpose of one is to regulate the voltage to a specific value such as 3.3V. Its accuracy to this voltage across temperature and load current is another consideration as is its maximum load. The dropout voltage value will be particularly important with battery applications.
Check the datasheet to determine which pins are the ground, input and output.
Attach the red wire to the input and the black wire to the ground, the multimeter should give a reading higher than the regulators' output value. If not then there is a power supply issue.
Attach the red to the ground and the black wire the output, the multimeter should then give the regulators' output value (plus minus its accuracy). If not then the regulator is likely to be faulty.
Description:
Texas Instruments LM340 series three terminal positive voltage
regulators are for use in fixed voltage regulation. There are no external parts required unless you want to adjust the outputs. The linear voltage regulators feature safe area compensation, internal current limiting ...
Description:
Texas Instruments (TI) LM350 series is an adjustable
linear voltage regulator. The 3-terminal positive voltage regulator can offer an output current of 3A and more with an output voltage ranging between 1.2 to 33 V. TIs easy to use LM350 ...
Description:
Texas Instruments offer a range of linear voltage
regulators which include LM78, LM78L and the LM78M Series that are intended for fixed voltage regulation. The three terminal positive regulators have current outputs more than 1A (LM78xx), 100 mA (LM78Lxx) and ...
Description:
The Texas Instruments LM117/LM317 series of adjustable three-terminal
positive voltage regulators are available with current ratings of 0.1, 0.5 and 1.5A. Output voltage range is from 1.25 V to 37 V and is set by two external resistors. These robust ...