TSR1-2450 linear regulator by Traco Power

Linear regulators, such as the LM7805, offer affordable voltage regulation. However, their linear operation principle results in high losses and substantial heat dissipation. To address these limitations, Traco Power introduces the TSR1-2450 series as a pin-compatible replacement with improved efficiency over the LM7805. 

Traco Power has designed the TSR1-2450 linear regulator replacement in a TO-220 housing, allowing for easy integration as a direct replacement for the existing LM7805 IC. The pinout of the TSR1-2450 matches that of the LM7805, facilitating a seamless transition.  

pinout of the TSR1-2450

By referring to the datasheet available at https://www.tracopower.com/sites/default/files/products/datasheets/tsr1_datasheet.pdf, one can explore multiple versions of the TSR1 series. For instance, the TSR1-2412 provides an output voltage of 1.2V, lower than the LM78xx series. On the other end, the TSR1-24150 matches the LM7815 with a 15V output. 

TSR1-2412 provides an output voltage of 1.2V

One notable advantage of the TSR1-2450 is its improved voltage regulation accuracy. The datasheet specifies a worst-case scenario of +/- 2% accuracy, and the switch-mode voltage output ripple is limited to a maximum of 75 mV peak-to-peak (Typ). Additionally, the switch-on overshoot remains below 1%.  

Environmental specifications for the TSR1-2450 series allow for operation within a temperature range of 40 to 85 degrees Celsius. The regulator incorporates over-temperature monitoring, and thermal shutdown is triggered at 150 degrees Celsius to prevent damage.  

Switch mode regulator performance on TSR 1-2450

Traco Power has packaged the switch-mode regulator in a TO-220 analogon format for the TSR1-2450 series. When paired with the EMI filter described in detail at https://www.tracopower.com/int/series/tsr-1, Traco Power assures compliance with EN 55032 class A EMI regulations.  

tsr-1, Traco Power assures compliance with EN 55032 class A EMI regulations

The regulator operates at a nominal switching frequency of 500 kHz, with dynamic adjustment ranging between 400 and 600 kHz.  

Availability and pricing

In terms of availability and pricing, the TSR1-2450 series is priced at around 5 EUR per piece when purchasing approximately 100 units (accurate as per the date of publication). Although slightly higher than dedicated integrated circuits, the TSR1-2450 offers significant PCB space savings and reduced pick-and-place costs, which offset the price difference. In many cases, the regulator can be used without an external filtering capacitor.  


The TSR1-2450 voltage regulator series serves as a drop-in replacement for LM78xx linear regulators. If the powered circuit can tolerate slightly higher output ripple and is not susceptible to potential spurious emissions, adopting the TSR1-2450 provides substantially improved power efficiency.