Audio switch and amplifiers for USB-C applications

The FSA4480 is a high-performance USB Type-C port multimedia switch that supports analogue audio headsets allowing a common USB Type-C port to pass USB2.0 signals, analogue audio and analogue microphone signals.

The device, which supports an audio sense path, is a fully integrated and optimised solution that eases design-in and minimises overall solution footprint. It includes integrated high voltage protection up to 20VDC, and offers pinout support for both OMTP and CTIA - sometimes known as American Headset Jack (AHJ) - smartphone headset standards. There is overvoltage protection (OVP) on the common node pins and the unplugging of any audio device is automatically detected.

With its integrated I2C interface, the FSA4480 is controlled by a host processor and audio ‘pop and click’ is highly reduced as the change is made. Housed in a small WLCSP chipscale package measuring just 2.24mm x 2.28mm x 0.5mm, the device is suited to space-constrained mobile applications such as smartphones, tablets, digital cameras and speakers. It can also be utilised in computing devices including laptops, desktops and hybrid notebooks.

The NCS21x family of bi-directional current sense amplifiers which include integrated, matched precision resistors, that offer an accurate, compact system design for measuring small differential voltages. The devices are able to detect common mode voltages in the range -0.3 to 26V, making them suitable for both high-side and low-side current sensing.

The zero-drift architecture of the NCS21xR provides a low input offset voltage (as low as 35µV) and low offset drift (as low as 0.5µV/°C). Together with integrated gain setting components, these devices are capable of sensing smaller voltage drops across the shunt, providing a higher gain accuracy and superior temperature performance.

Offered in 50/ 100/ 200, and 500/ gain options with a maximum gain error of ±1%, these devices consume a low quiescent current of 40μA, which improves efficiency and makes them appropriate for power conscious, battery-powered applications.

The small SC-70 and UQFN packages make them suitable for monitoring charging and discharging current for battery management in handheld applications such as smartphones, tablets and laptops.

With the adoption of USB Type-C in rapid growth markets such as hybrid and electric vehicles and several consumer products, these current sense amplifiers have noted presence in the power management, motor control and signal conditioning blocks.

“Our new multimedia switch and current sense amplifiers play an important role in managing the USB Type-C interface in modern mobile devices.” said Wiren Perera, who heads IoT at ON Semiconductor.

“The highly-integrated designs, low-power operation and small size mean they are suitable for tablets and smartphones where space is limited and power budgets are important. Furthermore, the current sense amplifiers can be instrumental in controlling power in larger applications including white goods and electric vehicles.”