Lightning surge and ESD protection

Paul Boughton

Littelfuse Inc has introduced the SP3312T Series 3.3V, 15A TVS Diode Array (SPA Diodes), which integrates four channels (two differential pairs) of low capacitance diodes to protect sensitive I/O pins from damage due to lightning-induced surge events and electrostatic discharge (ESD).

When compared with similar market solutions, the SP3312T Series provides circuit designers with 71% lower capacitance solution than other devices, which helps preserve signal integrity and minimise data loss. It also provides up to 150 percent higher power handling capacity than competing solutions. This robust device can safely absorb up to 15A per IEC 61000-4-5 (tp=8/20μs) without performance degradation and a minimum ±30kV ESD per IEC 61000-4-2.

Targeted applications include 10/100/1000 Ethernet, LAN/WAN equipment, home automation and security, which benefits from the SP3312T superior clamping performance in a space-saving 2.0 x 1.0mm μDFN-08 package with a typical height of 0.40mm Ultra fast acting silicon-based ESD protection, designed to shunt transient voltage events at a level just above standard operating voltages provides a superior choice when compared to existing solutions.

All SP3312T Series TVS Diode Arrays offer these key benefits:

* Excellent surge protection with a peak pulse power rating of 250W. Compared to similar market solutions, the SP3312T Series offers far more overhead to electrical threats defined by regulatory standards.

* Negligible variability in capacitance over the operating voltage range allows for improved signal integrity of the lines the device is protecting, as well as less eye diagram degradation when compared with competing solutions.

* 15A peak current ESD protection allows manufacturers to claim ESD protection above the maximum level stated in the IEC standard and protects against a multitude of other threats to ensure product reliability in the field.

* Small form factor µDFN-08 package (1.8x2.0x0.554mm) allows straight-through routing, so the PCB trace can be routed beneath the device without the need for stub traces that can cause signal degradation.