Now we will talk about a rather popular step-down converter based on the LM2596 chip. The Chinese sell ready-made fees for a penny, while they have very good output characteristics. Since this is a pulse converter, the dissipated heat, unlike the linear stabilizer, is minimal, the efficiency is up to 92%.
For ease of adjustment, if you plan to use this module as a power supply, the blue trimming resistor is replaced with two resistor variables connected in series: one for coarse adjustment, the other for fine adjustment. In addition to the LBP, this stabilizer device can be used to power the phone, LED strips, various sirens and low-power incandescent lamps.
You can supply DC voltage from 4 to 35 V to the input, and only 1.23 to 30 V at the output. The maximum output current is 3 A. A pulsed step-down converter operates at a frequency of 120 kHz, there is no voltage ripple at the output exceed 30 mV. Also, this device has an extremely wide range of operating temperature: from -45 to +85 degrees Celsius. The dimensions of the board are 43 by 21 by 14 mm.
Cost: ~ 43