ON Semiconductor introduced the NCP362 – described as the industry’s first overvoltage protection (OVP) device with both integrated current protection and high-speed electrostatic discharge (ESD) protection for USB 2.0 applications in portable, telecom, consumer and computing systems.
This integrated device is said to significantly improves safety of USB ports by streamlining design in portable electronics by eliminating the need for standalone OVP, overcurrent protection (OCP) and transient voltage suppressor (TVS) components that have – until now – been necessary to protect vulnerable portable devices against electrical surge damage and electronic discharge from host, wall adapters, human body and unsuitable after-market ac-dc adapters.
The new NCP362, which is placed behind the USB or bottom connector, provides +20V front end protection for the downstream USB port, thanks to an integrated power MOSFET that can handle 500mA.
Because long cables can induce ringing due to serial inductance in the USB cable, the NCP362 has been designed to open the VBUS line when the voltage transient exceeds the internal overvoltage threshold (OVLO), which is internally set to 5.675V. This threshold value can be changed by a metal tweak if a different value is needed for a specific application. In addition, OCP is available, opening the internal MOSFET if the downstream VBUS’s load exceeds 750mA, supporting 500mA – continuous – for the USB ports. This current clamp value can be also adjusted to a lower value to be compliant to 100mA single port or dual one.
Both protections are very fast – at fewer than 100 nano-seconds – offering an efficient protection level for the downstream transceiver, battery charger devices or Lithium battery to be charged. In addition, the NCP362 offers system level IEC 61000-4-2 +/-15kV ESD protection. The part integrates high-speed ESD diodes for data lines (D+ and D-) and TVS for VBUS pin of the USB ports. Due to the very low capacitance of integrated ESD diodes (0.5pF), this device is compliant with the USB 2.0 protocol. Depending on the selected NCP362x version (see ordering table in the product datasheet), VBUS TVS or D+/D- (or both) are integrated in the same package.
The NCP362xMTBG is now available in a 2 x 2.5 x 0.55mm DFN, Pb-free, RoHS compliant package. It is budgetary priced at $0.42 per unit in 3,000 unit quantities.