Application of adjustable voltage regulator W317

It is the application circuit of three-terminal integrated adjustable voltage regulator CW317. It is known from the parameter table that the maximum input voltage of tCW317
is 40V, and the output voltage adjustment range is continuously adjustable from 1.25 to 37V. Its voltage adjustment function is completed through a
fixed resistor Ri and a potentiometer RP. The resistance of the resistor Ri is 240fl, which is connected between the voltage-stabilizing output terminal vo and the adjustment
terminal ADj. The voltage at both ends is 1.25V. Due to the voltage stabilizing effect of the voltage regulator , the voltage on Ri remains unchanged
, and the current flowing through Ri is a constant current, and its value is, Rl - REF/R1; 1.25V/2400≈5mAa