Littelfuse Launches TPSMD-FL TVS Diodes for Simplified ISO 7637 Load-Dump Protection
Littelfuse has introduced the TPSMD-FL Series FlatSuppressX™ TVS diodes, a new automotive-grade family aimed squarely at one of the toughest problems in 12 V vehicle electrical design: surviving a load-dump transient without piling on extra protection components. The series is built specifically to simplify ISO 7637-2 Pulse 5b load-dump protection for 12 V vehicle electronics, a pulse condition that occurs when the alternator is charging and the battery is suddenly disconnected, sending a high-energy surge down the power rail toward every connected module. mesago
What sets this series apart from a standard TVS diode is the clamping behavior. Ordinary TVS diodes let the transient voltage rise to levels that often demand additional protection circuitry downstream, whereas the TPSMD-FL Series uses Littelfuse's proprietary FlatSuppressX technology to hold a low, flat, and stable clamping voltage throughout the high-energy event. In practical terms, that flatter clamping curve gives automotive engineers more margin against a demanding pulse using a single device, rather than stacking a TVS diode with a secondary suppressor or additional passive components to bring the residual voltage down to a safe level for downstream ICs.
The devices are rated for 3000 W of peak pulse power dissipation and come in the compact surface-mount DO-214AB package, with AEC-Q101 qualification confirming they meet automotive reliability standards. Commenting on the launch, Littelfuse's Charlie Cai, Director of Product Management for the Protection Business, framed the series as a response to designers' ongoing struggle to protect increasingly sensitive electronics from load-dump transients without adding cost and complexity, noting that the low clamping performance is intended to help systems meet Pulse 5b requirements with fewer added protection devices.
Key Specifications
| Parameter | Specification |
| Series | TPSMD-FL (FlatSuppressX™) |
| Peak pulse power dissipation | 3000 W |
| Package | DO-214AB (surface-mount) |
| Automotive qualification | AEC-Q101 |
| ESD protection (IEC 61000-4-2) | Up to 30 kV air discharge / 30 kV contact discharge |
| Target standard | ISO 7637-2 Pulse 5b (load dump) |
| System voltage | 12 V automotive networks |
| Clamping behavior | FlatSuppressX foldback I-V characteristic — low, stable clamping voltage under transient stress |
Key Features
- Excellent low-clamping performance, engineered specifically to keep residual voltage low during a load-dump event
- FlatSuppressX technology, advanced foldback I-V characteristic that maintains a flat, stable clamping voltage rather than letting it spike
- 3000 W peak pulse power capability for robust surge protection
- Built for ISO 7637-2 Pulse 5b compliance in 12 V automotive systems
- AEC-Q101 qualified for automotive-grade reliability
- Compact DO-214AB surface-mount footprint to help optimize board space
- IEC 61000-4-2 ESD protection up to 30 kV air and contact discharge
Applications
The TPSMD-FL Series is positioned for 12 V vehicle subsystems where load-dump events are a design concern, including:
- Zonal control modules
- Powertrain electronics
- Infotainment systems
- Body control modules
- Other 12 V automotive electronic subsystems requiring load-dump protection with reduced secondary circuitry
Availability
Littelfuse announced the TPSMD-FL Series with Product details, and the datasheet, as it becomes available, can be found on the official product page: Littelfuse TPSMD-FL Series. For distributor stock, checking Littelfuse's authorised channels (DigiKey, Mouser, etc.) once the part numbers are indexed would give you real-time pricing and lead times. The press materials I pulled from didn't include individual part numbers or a distributor SKU list yet, so I'd treat that as still rolling out.
