TI 公司的TCS2315 GPRS手机解决方案是第三代基于GSM的超低成本手机，采用先进的65-nm工艺技术，在单片上集成了TMS320C54x™ DSP 和ARM7核以及数字RF DRP™ 技术，具有高性能以及强大的功能如GPRS功能，内置的VGA功能支持JPEG编译码和先进的图像功能如旋转和变焦等，用来在PC和手机间数据传输的USB连接以及蓝牙连接等，主要适合印度，中国，俄罗斯和巴西等国市场。本文介绍了TCS2315 GPRS手机解决方案的主要性能特点和指标以及方框图。
TIs third-generation GSM-based solutions for the Ultra Low-Cost (ULC) Handsets
Leveraging an advanced 65-nm process with TMS320C54x™ DSP and ARM7 cores in the same package, the TCS2315 GPRS solution integrates TIs breakthrough digital RF DRP™ technology to offer the most compelling user experience in Ultra Low-Cost (ULC) handsets. Part of the LoCosto ULC family, the TCS2315 enables handsets with high performance, robust functionality and innovative form factors in the most price-sensitive handsets. Ideal for emerging markets such as India, China, Russia and Brazil where the next billion subscribers will come from, the scalability and flexibility of the TCS2315 LoCosto ULC GPRS chipset also allow it to be deployed in enhanced handsets for value-conscious segments in more mature markets.
Software portability from one generation of LoCosto solution to the next gives manufacturers and operators the ability to rapidly and cost-effectively differentiate handsets and service offerings for both emerging and mature markets, crossing over regional borders, language barriers and subscriber requirements.
A set of enhanced capabilities are now possible in ULC handsets, such as a relatively high-resolution color display without requiring additional external SRAM, VGA camera support, MP3 playback and mass storage (SD/MMC), USB and Bluetooth® connectivity, high-end full duplex voice quality, a MIDI player with 32 polyphonics, MP3 and polyphonic ringers, longer talk time and standby time, stereo FM radio connectivity, USB charging, handsfree speakerphone operation, vibration ringer, headset support and other functionality.
Equipped with TIs scalable and hardware-based M-Shield™ security technology, a TCS2315 handset offers ironclad protection of the owners personal information. M-Shield also prevents the unlocking of the handsets SIMlock code, defeating attempts to switch networks. High-value content and IP can be fully protected from tampering, piracy and malicious attacks.
Innovative user form factors such as ultra-slim, clamshell and candybar handsets are possible because of the reduced component count and PCB board space requirements brought about by the smaller 65-nm process node, increased integration, and advanced packaging technologies for a single-chip solution. In addition, a smaller PCB area requirement allows a handset to support larger batteries for a longer battery life enabling extended standby and talk times. The superb full-duplex quality of voice service of the
“LoCosto ULC” solutions are comparable to more expensive handsets. In fact, the voice loudness on both ends of a call can be improved by 7 dB or practically twice as loud. Moreover, voice chopping and double talk are reduced dramatically, making handsets based on the TCS2305 and TCS2315 solutions very effective in handsfree applications and noisy environments, characteristic of densely populated emerging markets. The TCS2305 and TCS2315 also offer SMS text messaging, a Universal Subscriber Identity
Module (USIM) interface for SIM cards and support for a standard keypad and joy stick.
Lowering the power dissipation in the advanced “LoCosto ULC” solutions extend the battery life of a handset, lengthening the standby and talk times for users. “LoCosto ULC” single-chip platform integrates power management functions for best-in-class power consumption levels and supports USB charging for universal and easy charger access. This eliminates the need to supply a charger with the phone (saving costs) and minimizes electronic waste from incompatible or obsolete chargers.
Concerns over the security of wireless handsets are completely mitigated by TI’s scalable and hardware-based M-Shield™ technology. The “LoCosto ULC” solutions take advantage of M-Shield technology to safeguard not just the handset owner’s sensitive personal information, but it also defeats malicious attempts to unlock the handset’s SIMlock code. Cracking the SIMlock code can increase subscriber churn because users are able to switch a handset that had been locked to one network to another provider’s network. To reduce phone theft and protect the service provider’s investment in subsidized handsets, TI’s M-Shield technology secures the contents of flash memory,
including boot code, and provides robust SIMLock and handset’s International Mobile Equipment Identity (IMEI) protection. This level of protection is simply not possible with software-based security systems.
TI’s M-Shield security technology includes secure read-only memory (ROM), unique hardware-based public keys, and other protection measures to safeguard valuable information, data and software stored on a handset, including sensitive personal information of handset owners as well as the device’s boot code and other critical firmware modules provided by the handset manufacturer. The investment handset manufacturers have made in developing software and other intellectual property (IP) is protected against piracy and the handset itself is safeguarded against malicious attackers attempting to install viruses, worms and other unwanted software on the device.
Fabricating the “LoCosto ULC” solutions with 65-nm process technology as well as several other chip- and system-level cost optimization techniques all contribute to the device’s sustainable ULC characteristics. For example, the electronic bill of materials (eBOM) for an entry-level ULC handset is reduced by up to 25 percent with the “LoCosto ULC” solutions compared with the previous generation. Additionally, fabricating the chip at a smaller process node means that the chip itself is substantially smaller. This, along with component reduction, reduces the size of a handset’s PCB, lowering the manufacturing cost of the cell phone. Integration of the power management with the digital baseband into a single chip also yields reduction in the modem PCB area.
Other system-level cost reduction features include the ability of TCS2305 and TCS2315 solutions to support a full 128 x 160, 65-k color display with no additional external SRAM memory. Circuitry for power management for phone peripherals like headsets and battery charging is also integrated on-chip to further reduce costs by lowering chip count.
Integrating TIs innovative DRP RF architecture into the TCS2305 and TCS2315 solutions add another dimension to lowering the cost of a mobile phone. DRP technology applies digital techniques to simplify radio frequency processing and dramatically cuts the cost and power consumption of transmitting and receiving information wirelessly. Processing radio signals with digital logic can significantly simplify the implementation and enhance the scalability of wireless communications capabilities.
By integrating DRP technology into the LoCosto family of wireless solutions, functions that were previously implemented in discrete devices have now been combined in a single-chip solution. With the RF section included in one device, space requirements and component counts are reduced. At the same time, interconnects are minimized, greatly improving the handset’s reliability.
By digitizing analog functionality, testability and manufacturing cycle time are improved with built-in calibration, drift effects are reduced and auto-compensation for process and temperature variances is enabled. All of these advantages add to the cost savings by reducing the size of the underlying platform and enabling handsets in sleeker, more compact form factors.
