Electric competition 2596 adjustable power supply

Adjustable switching power supply designed using 2596-ADJ chip,
1. Good output linearity and adjustable load
2. Output current can be as high as 3A
3. Input voltage can be as high as 40V
4. Using 150KHz internal oscillation frequency, it belongs to the second generation switching voltage Regulator, low power consumption, high efficiency
5. Low power consumption standby mode, the typical value of IQ is 80μA
6. TTL power-off capability
7. With overheating protection and current limiting protection function
4.5V≤VIN≤40V, adjustable output voltage
The calculation of the output voltage in the range of 1.2V～37V±4% :

Vout=Vref*(1+R2/R1)

where Vref=1.23V,

R2=R1*(Vout/Vref-1)

In order to ensure the output stability, R1 is selected as standard A resistor with a resistance value of 1KΩ and an accuracy of 1% is called.

CIN---680μF/50V COUT---220μF/35V R1---1K,1%

D1---5A/40V IN5825 L1---47μH

PCB requirements:
(1) The feedback line should be kept away from the inductor;
(2) The lines should be thicker and shorter: pin 1 and the positive electrode of the capacitor, pin 2 and the cathode of the Schottky diode, pin 2 and the inductor, the other end of the inductor and the positive electrode of the capacitor at the output end (the negative electrode is directly laid with copper);
(3) Adjust the output The voltage resistors R1 and R2 should be close to pin 4 of LM2596.
**Physical test**! [19FE43E8278A946BD5923E73EA5F84F4.jpg] Supply 5v
! [QQ picture 20230714095012.jpg] Adjust the potentiometer
! [5327.jpg] ! [4095124.jpg] The maximum is close to the power supply voltage here.
12v repeated test
![0714095233.jpg]