Device Integrates RF And Baseband Circuits

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The Bluetooth market is steadily growing, and will continue to do so until 2005 and possibly beyond. According to Toshiba America Electronic Components, Inc. (TAEC), the bulk of this growth will occur in the cellular area. Cellular phones and personal digital assistants (PDAs) will harvest an increasing number of Bluetooth applications, ranging from wireless headsets to printing capabilities. As one of the five original Bluetooth Special Interest Group (SIG) members, Toshiba Corp. is actively preparing to meet this market growth.

The company's strategy is to roll out a complete lineup of Bluetooth semiconductor products for TAEC's North American customer base. For its first step, it has announced a single-chip Bluetooth large-scale integration (LSI) that integrates radio-frequency (RF) and baseband circuits (see figure). To achieve this single-chip solution, Toshiba used complementary-metal-oxide-semiconductor (CMOS) process technology for the RF circuit instead of the usual bipolar process technology. By applying the same process technology to both the baseband and RF circuits, TAEC created a LSI chip that requires fewer external components.

Designated the TC35654, this solution can be housed in a 7-×-7-mm plastic-wireless-frequency land-grid array (PWFLGA) that is only 0.8 mm high. Compared to a solution that utilizes separate RF, baseband, and mask ROM integrated circuits (ICs), the TC35654 occupies approximately 65% less space on a printed-circuit board (PCB). The TC35654 will therefore fit into small-form-factor products like mice, keyboards, and other personal-computer peripherals. In addition, the company sees a viable market for this solution in many emerging wireless-connectivity applications, such as telematics, set-top boxes, small-office/home-office routers, and residential gateways.

Though it will pursue these potential opportunities, this single-chip device adheres to the company's forecasts by mainly concentrating on cellular phones, PDAs, and other handheld products. As further proof of its dedication to this market segment, the new LSI incorporates Bluetooth core circuit technology that is licensed from Nokia. With this technology, the TC35654 should be able to ensure reliable interoperability between multiple Bluetooth-enabled platforms.

It also offers low power consumption. The TC35654 supports low-power-consumption control mode, or standby mode. The device was actually designed for lowest-power consumption in standby mode.

In addition, the solution boasts an impressive list of specifications. For its RF function, the LSI houses a 2.4-GHz low-noise amplifier (LNA) on chip, as well as a mixer, voltage-controlled oscillator (VCO), and power amplifier. To ease compliance worries, its baseband function conforms to Bluetooth Version 1.1. The TC35654 supports Class 2 and 3 output power for transmission. As its processor core, it contains an ARM7TDMI. The power supply for the TC35654 is 1.8 or 3.0 V I/O, 1.5 V core, and 2.5 V RF.

The solution also flaunts built-in memory. It contains a buffer RAM and mask ROM for installing link-manager-protocol/host-control-interface software. If more memory is needed, designers can take advantage of its external interfaces for add-on RAM, external Flash ROM, and external EEPROM.

Concerning its host interface, the TC35654 boasts a high-speed UART of up to 921.6 kbps. It offers a pulse-code-modulation (PCM) digital audio interface as well. This on-chip UART/PCM interface enables the construction of several kinds of Bluetooth applications. For test control, the solution has a JTAG interface. Among its other features is a built-in signal-strength indicator.

To round out news of the TC35654, the company has announced the North American availability of a complete lineup of Bluetooth semiconductor products. They include RF and baseband chip sets and a full software protocol stack. Specifically, TAEC has introduced and begun sampling a new Bluetooth RF IC. The TB31296FT is based on silicon-germanium BiCMOS technology. In addition, Toshiba is developing Bluetooth intellectual property for a system-on-a-chip/application-specific-integrated-circuit (SoC/ASIC) implementation.

Engineering samples of the TC35654 are available now at $5.00 each in 100,000-piece quantities. Mass production is slated to begin in July at an initial run rate of 50,000 units per month. The solution comes packaged in a 113-pin PWFLGA with a 0.5-mm ball pitch.