Compact TVS diodes offer “complete ESD protection” of USB-C
Compact TVS diodes with parameters matched to the various ports of the USB-C port as well as other high-speed interfaces, have been released by TDK.
Transient voltage suppressor (TVS) diodes with very low parasitic capacitance values and low clamping voltage are required especially for the high-speed ports (Tx / Rx) of USB-C, which operate at up to 40 Gbit per second with USB4 version 1.
TDK has released the B74111U0033M060 and B74121U0033M060 TVS diodes. They have very low capacitance values of 0.48 and 0.65 pF at 1.0MHz, respectively, which means that signal integrity is not compromised. The clamping voltages are only 3.8 or 3.9V with an ITLP (intrinsic transient latch-up phenomenon) of 8.0A. The diodes are designed for ESD discharge voltages of up to 15kV and manufactured in the compact WLCSP 01005 and WLCSP 0201 packages. They are flat, with heights of 100 micron (B74111U0033M060) and 150 micron (B74121U0033M060). This means that the TVS diodes can also be integrated into USB-C SIP modules, advised TDK.
Other diodes in the series are the B74111U0055M060 and B74121U0055M060 diodes which have maximum DC voltages of up to 5.5V making them suitable for the conventional USB2.0 data bus of USB-C (D+ / D-). Clamping voltages are 3.9 and 4.0V with an ITLP of 8.0A. They are also designed for a high ESD discharge voltage of up to 15kV and have the same housing and heights as the B74111U0033M060 and B74121U0033M060.
Power lines VBUS (CC / SBU) can be used to transmit a maximum of 100W at voltages of up to 20V and currents of 5.0A. For safe ESD protection, TDK offers the B74121G0160M060 with a maximum working voltage of 16V and B74121G0200M060 with a value of 20V and clamping voltages of 23 and 27V, respectively, at an ITLP of 8.0A. They feature capacitance values of 6.0 and 5.0pF, respectively, with high linearity and are rated for ESD contact discharge voltages of 15kV. They are also designed in the compact WLCSP 0201 form factor with a height of 150 micron.
In total, up to three different types of TVS diodes are required for complete ESD protection of USB-C due to the different requirements. In addition to USB-C, the ESD protection components can also be used for other high-speed interfaces such as Thunderbolt, HDMI, Display Port, FireWire, DVI, S-ATA or SWP/NFC. Typical end devices are smartphones, tablets, notebooks, wearables, or network components.
