LONDON CSR plc has joined the growing list of companies over the past few days announcing their roadmaps for integrating Wi-Fi and Bluetooth capabilities in chips targeting mobile phones. Some of these also include FM radio functionality.
Bluetooth chip market leader CSR (Cambridge, England) suggests its device, which integrates the first version of its UniFi wireless LAN technology with the second iteration to follow by the middle of the year and a choice of Bluetooth cores, has significant power consumption advantages over devices from Broadcom Corp., Texas Instruments Inc. , Marvell or NXP Semiconductors.
Dubbed the UniVox Mobile, the reference design, which uses the company's tried and tested software stacks, ensures coexistence between both 2.4GHz radios.
According to Simon Finch, head of CSR's Wi-Fi business unit, "because we use the same building blocks that we already have, the unified chip can be configured to cope with a multitude of coexistence scenarios."
Finch said Wi-Fi throughput remains high even when Bluetooth is used concurrently, by using Collision Detection Logic.
He told EE Times Europe the highest data rates that can be achieved reach 23Mbit/s when Bluetooth is deactivated, reducing to 18Mbit/s with Bluetooth switched on.
"The key differentiator for us is power consumption, and competitive analysis indicates that we are well ahead of the competition here," said Finch.
He quotes typical cellular power at 5mW for idle that is listening to both Wi-Fi beacons and GSM paging and 288mW for a VoIP call, with the corresponding Wi-Fi chip, including PA and power management, drawing 7mW and 68 mW.
"Taken together, that translates to 250 hours in standby mode and 8 hours VoIP talk time in a phone. We have done analysis that shows phones using other devices are significantly more power hungry in both modes. This is a real winner for us; the others are not there in terms of power."
The Bluetooth part can be either BlueCore4-ROM or BlueCore5-FM and the hardware architecture is platform independent so can be used via standard interfaces with most cellular baseband processors and chipsets. The SDIO/SPI interface is used for Wi-Fi and UART/12S for Bluetooth.
Finch said the first handsets to use the combo device are likely to be enhanced versions of existing models, with phones designed from the ground up likely to be available early next year. "We are working with a couple of companies at the moment."