OnChip Devices Introduces Low Capacitance ESD Protection Chips For USB Ports
OnChip Devices has introduced low capacitance ESD protection devices for single and dual USB ports. The devices protect the two data lines and the power rail of the USB 2.0 high speed interface. The low sub-1pF line-capacitance of the new ESD2100-02 and ESD2100-04 ensures minimal distortion of the 480-Mbit/s USB 2.0 signal. The devices are said to offer optimum trade-off between low line-to-ground capacitance and compliance with IEC61000-4-2 level 4 (air discharge up to 15kV, contact discharge up to 8kV).
According to the company, new generation mobile computing and consumer products are increasingly susceptible to ESD events since they predominantly use integrated circuits (IC) with sub-micron geometries and lower working voltages. Furthermore, portable electronics are said to require lower capacitance to maintain the signal integrity of their high speed I/O ports. Traditional silicon TVS diodes are said to offer low ESD clamping voltage and fast response time, but their large line-capacitance is said to limit their use in high speed applications. Other solutions such as polymers and varistors offer low capacitance, but their high clamp-voltage limits their ability to adequately protect ICs from latch-up after an ESD event thereby causing soft errors.
The introduction of the ESD2100 family of products reflects the increasing use of higher data rates for interfaces in computer and consumer electronics. "USB is the most common port in all Computer Peripherals and Portable Consumer Electronics such as MP3 Players, Digital Cameras and Mobile Handsets." said Sona Joe, Product Marketing Manager. "The rail-to-rail topology of our ESD2100 provides protection of both upstream and downstream USB 2.0 (full speed) and on-the-go (OTG) ports. The additional ESD diode between the Vcc and Ground prevents charging of the Supply Line."
The OnChip ESD2100-02 offers 2-channels of ESD protection suitable for a single USB port. It is available immediately worldwide at US $0.11 in quantities of 10,000. Pricing for the ESD2100-04 with 4-channels of ESD protection suitable for two USB Ports is $0.15.
