TOLL4 Package: Why One Can Replace Two
Preface
It is nearly a universal industry consensus that the TO-252 package has long stood as the benchmark for SMD power devices. It strikes an optimal balance across cost, footprint size, thermal performance and manufacturability. For applications such as electric bicycles, lithium battery protection and switching power supplies, TO-252 has become an almost default choice. However, TO-252 has an inherent limitation: its fixed die pad area restricts the maximum chip size, capping its current handling capability.
Looking to achieve higher current ratings? The alternatives are either adopting the through-hole TO-220 package or paralleling two TO-252 devices. The former complicates design, while the latter raises costs. The TOLL4 package is developed precisely to address this pain point.
What is TOLL4?
Also known in the industry as PTO-252, TOLL4 is essentially an upgraded version of the standard TO-252 package.
Its footprint expands from the conventional TO-252 size of approximately 6.6×6.1mm to 10×7mm. The seemingly modest 3–4mm increase in width directly enables a larger die pad to accommodate bigger-sized chips. Most importantly, its pin layout is fully pin-to-pin compatible with TO-252. Existing PCBs require no redesign, allowing direct drop-in replacement for immediate usability — delivering exceptional practicality.
Core Advantages
- Full TO-252 compatibility with no PCB modifications requiredSimplifies product upgrade and layout adjustment significantly.
- Enlarged die pad supports larger chip integrationA larger chip size enables lower on-resistance RDS(ON)
- and higher current conduction capability.
The pulse current rating of Hekshetai’s TOLL4 packaged devices exceeds 200A. To put this into perspective: a single TOLL4 device can theoretically match the current handling capacity of two standard parallel-connected TO-252 devices, embodying the strength of one unit replacing two. This performance is conditional upon adequate thermal dissipation design.
A key technical detail worth noting: the HKTS190N03 and HKTS190N04 both feature a 190A current rating, yet one is rated 30V with 96W power dissipation and the other 40V with 65W. Why does higher voltage correspond to lower power rating? High-voltage devices adopt different breakdown margin designs and differ in thermal resistance characteristics. Therefore, current rating alone should not be the sole reference during component selection.
The HKTS80N06 has passed dedicated EAS testing with a 400mJ EAS withstand capability, ideal for scenarios requiring surge resistance, such as back EMF suppression during motor startup.
The super-junction HKTS13N65 (650V/13A) is perfectly suited for power adapters and LED driver applications.
Application Scenarios
Ideal for space-constrained applications demanding higher current capacity.
Typical use cases:
- E-bike motor controllers: PCB real estate is extremely limited, with a clear demand to reduce the number of parallel devices.
- Lithium battery protection boards: Multi-series battery packs require high-current MOSFETs that standard TO-252 devices cannot support.
- Secondary rectification for switching power supplies: High efficiency requirements call for low RDS(ON)
- to minimize power loss.
In short, TOLL4 serves as an ideal alternative for designs where TO-220 is desired but cannot fit within the limited layout space.
Conclusion
The evolution of semiconductor packages has never pursued blind performance breakthroughs, but rather targeted problem-solving. TOLL4 adopts no exotic new materials or complex processes; it simply enlarges the die pad area based on the classic TO-252 framework to accommodate larger chips. While it is not a revolutionary technological breakthrough, it delivers outstanding engineering practicality. It preserves existing PCB layouts and reduces the need for device paralleling, simplifying both supply chain management and production processing.
A key guideline for selection: TOLL4 is not a replacement for TO-220, but an enhanced iteration of TO-252. It perfectly meets the demand for TO-252 footprint compatibility paired with upgraded high-current performance.
As a long-term professional partner specializing in electronic manufacturing and packaging & testing services, Hekshetai not only provides high-performance SiC power devices, but also leverages mature packaging processes (TO-247, TO-220, etc.) and comprehensive testing capabilities to deliver reliable supply chain support and customized packaging solutions for customers.
We welcome inquiries and technical communication for your specific project requirements.