Littelfuse announced the TP5.0SMD-FL (5kW) and TP1KSMB-FL (1kW) Series FlatSuppressX TVS Diodes, designed to protect 48V automotive electronics from transient overvoltage events while delivering ultra-low and stable clamping performance.
Engineered for next-generation 48V systems in compliance with ISO 21780, the new TVS diodes address a critical challenge in automotive design: protecting increasingly sensitive ICs – such as DC/DC converters and gate drivers – without exceeding their absolute maximum ratings. Using Littelfuse’s proprietary FlatSuppressX technology, the devices maintain a near-constant, low clamping voltage during fast transients and high-energy surge events, helping designers reduce system stress and overall BOM cost.
Unlike conventional TVS devices, which can exhibit higher and variable clamping voltages, FlatSuppressX devices leverage an advanced foldback/snapback I-V characteristic to tightly control transient response while avoiding latch-up risk. This approach enables the use of lower voltage-rated components, improving design flexibility and cost efficiency.
“The key advantage of FlatSuppressX technology is its ability to deliver extremely low and stable clamping voltage in 48V systems,” said Charlie Cai, Director of Product Management, Protection Business, Littelfuse. “This allows engineers to protect sensitive ICs better while meeting ISO 21780 requirements and reducing total system cost without latch-up risk.”
The TP5.0SMD-FL Series provides up to 5000W peak pulse power capability in a DO-214AB (SMC) package. At the same time, the TP1KSMB-FL Series delivers 1000W in a compact DO-214AA (SMB) package, offering scalable protection options for different system requirements. Both series are AEC-Q101 qualified and designed for high-reliability automotive applications.
Key features and benefits
- FlatSuppressX technology: Exhibits a flatter clamping characteristic with a significantly lower clamping voltage than conventional TVS devices.
- High surge capability: 5kW (TP5.0SMD-FL) and 1kW (TP1KSMB-FL) options
- ISO 21780 alignment: Designed for 48V automotive system protection
- Enhanced system efficiency: Enables use of lower-rated downstream components
- AEC-Q101 qualified: Supports automotive-grade reliability
- Fast response time: Typically <1 ps for rapid transient suppression
- Low-profile, surface-mount packages: Optimise PCB space
The devices are optimised for protecting I/O interfaces, power buses, and other vulnerable circuits in automotive electronics, particularly in 48 V architectures.
Target markets and applications
- Automotive 48V systems (ISO 21780 compliant)
- Battery disconnect Units (BDUs)
- Zone control Units (ZCUs)
- Electric power steering (EPS) systems
- DC/DC converters and power distribution networks
By combining high surge capability with ultra-low clamping voltage, the TP5.0SMD-FL and TP1KSMB-FL Series help engineers design more robust, efficient, and cost-effective automotive electronics platforms.
FAQs – TP5.0SMD-FL and TP1KSMB-FL Series FlatSuppressX TVS Diodes
What is FlatSuppressX technology?
FlatSuppressX is a proprietary Littelfuse TVS architecture that uses advanced foldback/snapback behaviour to maintain a near-constant, low clamping voltage during transient events. Doing so improves protection accuracy compared to conventional TVS devices.
Why is low clamping voltage important in 48 V systems?
Lower clamping voltage reduces stress on sensitive ICs with tight absolute maximum ratings. This is critical in modern 48V architectures where power density and component sensitivity are increasing.
How do these devices reduce BOM cost?
By enabling lower clamping levels, designers can use lower-voltage-rated MOSFETs and power ICs, reducing component costs and improving overall system efficiency.
What applications are these TVS diodes best suited for?
They are ideal for 48V automotive electronics, including BDUs, ZCUs, EPS systems, and DC/DC converters, where compliance with ISO 21780 and robust transient protection are required.
How do they compare to conventional TVS diodes?
Conventional TVS devices often have higher and less predictable clamping voltages. FlatSuppressX devices provide a flatter, more controlled response, improving protection and reducing system-level risk.
Are these devices automotive-qualified?
Yes. Both series are AEC-Q101 qualified and designed for high-reliability automotive environments, including wide temperature operation and harsh transient conditions.
