Switchmode voltage regulator in to-3 package design and implementation by Harun Aktas (Bad Zwischenahn & Donauwörth). This is a switching voltage regulator based on the TPS56339DDCR from Texas Instruments for replace the obsolete LM323K. It is a synchronous buck (step-down) converter. It provides an output voltage of 5 V (or 12V, depending on L1 & Rfbt1 see BOM lists) . The input voltage can be 4,5 to 24 Volts with a continuous current of 3 amps! At room temperature, it does not need a heatsink! The switching voltage regulator operates with a frequency of 500kHz. This device has the same shape as the original TO-3 package. The TO-3 package was used in old devices like game consoles, computers from the 1980 and pinball machines. Therefore you can use this switching voltage regulator to replace your old linear regulators and prevent from damage your old machines. Extremely low ripple and noise! The Pins and the surface of the device are gold plated. The design of the regulator was done with precise calculation and test in the lab. The pcb traces was done to meet the radiation and emission regulations!