Wireless-device designers constantly operate under the mantra of "smaller, faster, lighter, and better." The parts that go into a handheld must therefore follow the same path of constant improvement. An example is the NLAS2066 from ON Semiconductor. This ultra-small analog device delivers an overvoltage-tolerant switch. It permits input, output, and USB lines to be shared on the same connector pins. The result is reduced size and lowered cost for handheld products like smart phones, PDAs, MP3 players, and digital still and video cameras.
Specifically, the NLAS2066 is a dual single-pole single-throw (SPST) switch. Its overvoltage tolerance and low Ron resistance enable it to be used to isolate USB lines. Those lines may then be shared with standard input/output (I/O) lines. In addition, the device meets the full USB specification. Regardless of operating voltage, it can withstand the USB requirement of up to 5.5 V for 24 hrs. The NLAS2066 may be operated at a low voltage, eliminating the need for an otherwise redundant 5.0-V power supply.
Because the device reduces the required number of power supplies and pins connected to the outside world, the cost of manufacturing a USB-enabled system is reduced. To cut the power consumption of the entire system, the device boasts a lower operating voltage and a reduction in the number of required power supplies. It therefore improves battery life while reducing weight. With reduced threshold levels in the control pins, the NLAS2066 permits a direct interface to a low-voltage microcontroller without the need for logic-level translation.
The NLAS2066 is offered in the ultra-small, 2-×-3-mm US8 package. It is priced at $0.25 per unit in 10,000-unit quantities.ON Semiconductor5005 E. McDowell Rd., Phoenix, AZ 85008; (602) 244-6600, www.onsemi.com.