New Industry Products

Littelfuse Introduces a Series of 50 Amp Unidirectional TVS Diode Arrays

October 19, 2020 by Gary Elinoff

The SPI1250 protects against multiple 30kV ESD strikes and can also dissipate a 50A 8/20μs surge event.

The SPI1250 is a discrete, unidirectional TVS diode, requiring less than a square millimeter of board space. It is fabricated in a proprietary silicon avalanche technology to provide a high degree protection for a wide range of electronic devices.


Littelfuse Introduces a Series of 50 Amp Unidirectional TVS Diode Arrays Figure
Image used courtesy of Littelfuse


Important Features 

Electrostatic Discharge

The device is rated to ±30 kV contact, and  ±30 kV air discharge as per IEC 61000-4-2


Electrical Fast Transient 

Also known as burst transient. As per IEC 61000-4-4, the SP1250 is rated at 40 amps for a 5/50 ns pulse 



The unit can absorb a 50 amp 8/20 μs pulse (as defined in IEC 61000-4-5 2nd edition)  

An 8/20 μs pulse, often used as a proxy for a lightning pulse, rises to its maximum in 8 microseconds. By the time 20 μs have passed, its intensity has receded to 50% of its maximum.


An 8/20 μs “lightning” pulse.
An 8/20 μs “lightning” pulse. Image courtesy of Littelfuse


Low Leakage Current

Typical leakage current is only 0.02 μA at 5 volts


Other Characteristics of the SP1250

  • Breakdown Voltage is 5.5 volts, typical
  • Reverse Standoff Voltage is 5 volts, maximum
  • Clamp Voltage is 8.7 volts, typical
  • Dynamic resistance is 0.05 ohms, typical
  • Diode Capacitance is 120 pF, typical

A full breakdown of SP1250 characteristics can be found on the data sheet


First of many members of a New Series?

It appears that at this point, only one member of the new series, the SP1250-01ETG, is currently available. While the series is touted as being AEC-Q101 qualified, there appears some ambiguity over the question as to whether this first device enjoys that distinction. (See electrical characteristics section in the product description).

In addition, the SPI1250 itself is not an array; it’s one TVS diode.  Indeed, the SOD882 it comes in only has two terminals. But, Littelfuse does manufacture many other TVS diode arrays, many are listed here. So, it is probably safe to assume that the SPI1250 will serve as the progenitor of what will be a series of TVS diode arrays as impressive as its originator.


Functional Block Diagram for the SP1250 as per the data sheet.
Functional Block Diagram for the SP1250 as per the data sheet. Image courtesy of Littelfuse


Applications for the SPI1250 include:

  • Consumer electronics
  • Computer peripherals
  • VBUS Protection
  • Servers
  • Point-of-Sale (POS) terminals
  • Test equipment 
  • Medical equipment
  • POS Terminals


Environmental Considerations

  • Halogen-free, lead-free and RoHS compliant 
  • Moisture Sensitivity Level (MSL -1) 
  • AEC-Q101 Qualified 


Physical Characteristics

The new TVS diodes operate over a temperature range of -40 to 125℃.

The devices are available in a tiny surface-mounted SOD882 package, with typical dimensions of approximately 1.0 x 0.6 x 0.5 mm.