The project presented here is a wide input voltage range non-isolated DC-DC Converter, that provides a regulated, adjustable output voltage. The operating input supply is 55V DC and output regulated from 1.2V to 50V DC. The project built using LM2576HVT-ADJ IC. Screw terminals provided for easy input and output connections, onboard power LED at the input, bridge rectifier for AC/DC Input, an onboard potentiometer to adjust the output voltage, etc. This is a low-profile board with a thermal area on PCB that acts as a heatsink. An additional LC filter using C5 and L2 that reduces the output ripple by a factor of 10 or more is included in this circuit. The device has a current limiting feature to prevent the switching current from exceeding a safe value during an accidental overload on output.
LM2576 DESCRIPTION
The LM2576 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving 3-A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3 V, 5 V, 12 V, 15 V, and an adjustable output version. Requiring a minimum number of external components, these regulators are simple to use and include fault protection and a fixed-frequency oscillator. The LM2576 series offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in some cases, no heat sink is required. A standard series of inductors optimized for use with the LM2576 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies. Other features include a ±4% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring 50-µA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.
Read more: 1.2V TO 50V @ 3A – ADJUSTABLE POWER SUPPLY WITH 55VDC INPUT
