WLAN chips
Increasingly, 802.11 wireless local-area networking (WLAN) capability is finding its way into cell phones and other mobile devices. Virtually all laptops and tablets have it, as do most smart phones. But it’s now showing up in lower-cost cell phones too. There also has been a push to equip battery-powered gadgets like cameras, games, and toys with Wi-Fi.
Intended for these types of portable consumer electronics, the Ralink Technology RT3180 and RT3680 are highly integrated 2.4-GHz and dual-band 802.11n WLAN chips (see the figure). They integrate mobile-specific functionality incorporating high-performance power amplifiers, low-noise amps, and other front-end components that enable low-cost and small form-factor designs for applications such as digital camcorders and cameras, mobile gaming platforms, and tablets.
An integrated power-management unit in the chips reduces external component count while enabling support for advanced low-power states—ideal for compact battery-powered devices. Embedded processors offload all 802.11n-related functions including support for Wake on Wireless LAN (WoWLAN). The RT3180 and RT3680 feature two-, three-, and four-wire Bluetooth coexistence mechanisms and a full set of interfaces including USB 2.0, SDIO 2.0, GSPI, UART, SPI, and I2C.
The RT8180 is a low-cost, single-chip Wi-Fi solution that addresses mobile-phone applications. It boasts a 150-Mbit/s 802.11n media access controller (MAC) and baseband; a high-performance, 19-dBm, 2.4-GHz radio and power amplifier; and a low-noise amp. An integrated transmit/receive switch provides support for two-antenna diversity that improves range and reliability.
Also, the RT8180 offers a mobile-centric SDIO 2.0 interface, integrated RAM and ROM memory, and an embedded power-management unit. It also features 100% host CPU offload capability, per-packet antenna diversity technology, power-management optimizations, support for WoWLAN, and other radio/baseband enhancements to increase range and reliability.
Samples of the RT3180 and RT3680 are available, and samples of the RT8180 will appear in the first quarter of 2011.