Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > RF/Microwave

Atmel rolls out second-gen VoIP chip for Wi-Fi apps

Posted: 20 Sep 2006 ?? ?Print Version ?Bookmark and Share

Keywords:Atmel? VoIP? AT76C902? 802.11a/g? Wi-Fi?

Atmel's AT76C902 VoIP chip

Atmel Corp. recently unveiled the AT76C902, the company's second generation VoIP chip designed for 802.11a/g wireless VoIP applications. The new chip runs the VoIP Session Initiation Protocol (SIP) stack, uCLinux OS, and firmware enabling 802.11a/g (Wi-Fi) and voice compression and decompression, all on a single chip.

The device consists of an ARM946 processor for VoIP call control, authentication and signalling functions, and two subsystemsan ARM7 and 802.11a/g media access controller (MAC) that implements the 802.11a/g protocols, and a TEAK TeakDSPCore and integrated voice codec for voice processing functions. Additionally, hardware security accelerators offer on-the-fly encryption, decryption and authentication support for AES, DES/3DES and TKIP, supporting WPA and WPA2.

Power saving features
This chip supports Wi-Fi Multimedia (WMM) and WMM Power Save modes. WMM adds QoS capabilities to Wi-Fi networks. WMM Power Save is an improvement to the 802.11e amendment adding advanced power management functionality to WMM. WMM Power Save is based on Unscheduled Automatic Power Save Delivery (U-APSD), which, like WMM, is based on Enhanced Distributed Channel Access (EDCA). U-APSD is a solution suited for dynamic environments where Wi-Fi is generally deployed and allows clients supporting U-APSD to download all or some of the frames buffered by the access point during unscheduled service periods.

By supporting U-APSD and Scheduled APSD (S-APSD), solutions based on Atmel's new VoIP chip have talk times of over six hours and stand-by times of over 220hrs on a 900mA battery. This is achieved even when the access point it is connected to does not support WMM APSD. Phones based on Atmel's new chip have been tested in-house against all access points within the Wi-Fi test plan and they interoperated with no issues. If the terminals are deployed and they support APSD but the access points can be replaced, the new chip will produce the best results for the existing terminals, Atmel said.

Development kit
To facilitate quick time-to-market and reduce engineering costs, a complete development kit (AT76C902-DK)including Atmel's AT76C902 VoIP processor, AT76C517.11a/g baseband, flash memory and the Airoha single-chip 802.11g RF transceiver with integrated Power Amplifier (AL2236)is available to qualified customers. The AT76C902-DK also includes a miniature-sized module design containing all critical sections of a stand-alone wireless VoIP phone. Included with the kit are complete schematics, BOM, a reference design, Gerbers and software. The VoIP SIP stack is licensed from Radvision.

The AT76C902, packaged in a 208-pin BGA, is in production. Pricing starts around $18 at 25,000 units.

Article Comments - Atmel rolls out second-gen VoIP chip...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top