LM217L/LM317L

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APPLICATION INFORMATION

The LM317L provides an internal reference

voltage

of

1.25V

between

the

output

and

adjustments terminals. This is used to set a

constant current flow across an external resistor

The device was designed to minimize the term

with line and load changes. Usually, the error term

requirement, all the regulator quiescent current is

returned to the output terminal, imposing a

minimum load current condition. If the load is

insufficient, the output voltage will rise.

Since the LM317L is a floating regulator and

"sees" only the input-to-output differential voltage,

supplies of very high voltage with respect to

ground can be regulated as long as the maximum

input-to-output

differential

is

not

exceeded.

Furthermore, programmable regulator are easily

obtainable and, by connecting a fixed resistor

between the adjustment and output, the device

can be used as a precision current regulator. In

order to optimize the load regulation, the current

as possible to the regulator, while the ground

load to provide remote ground sensing.

Figure 6: Basic Adjustable Regulator

Figure 7: Voltage Regulator with Protection Diodes