Rail-to-rail steering array for USB data lines
The STMicroelectronics USBLC6-2P6 is a steering (rail to rail) ESD protection array designed to clamp transients on high-speed data lines. Its two unidirectional channels match the D+ and D- pair on a USB port, shunting overvoltage to the supply rails without loading the signal path during normal operation.
Clamping voltage and breakdown margins
With a reverse standoff voltage of 5.25 V and a minimum breakdown of 6 V, the USBLC6-2P6 sits just above the 5 V USB bus voltage — it stays transparent during normal signalling but triggers before the downstream transceiver sees damage. The clamping voltage is 17 V at a peak pulse current of 5 A (8/20 µs waveform), which keeps the let-through voltage within the absolute maximum ratings of most USB 2.0 PHYs.
The SOT-666 package (1.6 mm × 1.2 mm body) fits tight PCB layouts near the USB connector; the 0.50 mm pitch demands careful solder-paste stencil design to avoid bridging.