RClamp1255P RailClamp® ESD Protection Semtech RClamp1255P Low Capacitance RailClamp® provides dedicated surge and ESD protection for uUSB ports. It is designed to replace multiple discrete components in portable applications. This device features low capacitance transient-voltage-suppression (TVS) diodes for protection of the USB data (DP,DM) and USB ID pins operating up to ±4V. These diodes provide ESD protection to ±10kV contact discharge per IEC 61000-4-2. An integrated 12V TVS diode is used for protection of the USB voltage bus. The VBus TVS is designed with a high surge current capability of 100A (tp=8/20us) and low clamping voltage.