索尼“单线接口技术”替代移动设备排线传输

索尼公司日前宣布，他们已经成功研发出一种“单线接口技术”，这是一种混合传输技术，可以用一条导线替代移动设备中的排线，完成数据传输和充电，使移动设备的内部配线得以简化。

传统上，移动设备要完成视频、音频、信号控制以及电力传输就需要数十根缆线，例如铰链或旋转部件。索尼表示，随着功能日益复杂、显示器分辨率也越来越高，目前翻盖手机的屏幕排线中包含的导线数量平均达到22根，导致主板接口尺寸庞大，排线弯曲难度也随之增加。索尼的目标是尽快实施这一技术，以提高移动设备设计的灵活性和可靠性。

索尼新的方案通过时分双工和多工技术，只使用一条导线就可同时双向传输多种数据信号，甚至还能同时提供直流供电。该技术可在60cm距离内提供 940Mbps的数据传输率。使用双芯同轴线缆可提供1.5V或3V供电，供电电流600mA。传输方案本身的待机功耗为0.3mW，数据传输功耗10～80mW。

据称，该单线接口技术可传输视频(屏幕显示和摄像头)、音频以及控制信号，完全替代翻盖手机中的屏幕排线，可明显提高设备可靠性。未来设计师在设计含有移动部件的便携设备时，灵活性也可大大增强。

索尼将把该技术授权给罗姆半导体(ROHM)，合作开发该方案的模拟供电部分，目标是提供同时包含数字和模拟部分的单芯片解决方案。或许在不久后，我们就能看到只用一条导线传输的索尼爱立信手机或其他索尼便携产品。

Newly-developed technology facilitates both internal data transmission and power supply with a single cable

Sony Corporation ('Sony') has developed 'single wire interface technology', a hybrid transmission technology which facilitates both data and power transmissions through a single cable.

This technology enables the internal wiring of a mobile device to be streamlined through a single cable (copper wire). Conventionally, the video, audio and control signals as well as the power transmission were spread out over several dozen cables within the movable mechanisms of mobile devices, such as hinges or rotating parts. Sony aims to promptly implement this technology to improve design flexibility, reliability and durability for mobile devices with movable mechanisms.

In recent years, mobile devices have become ever more sophisticated in terms of advanced functionality and high resolution displays. As a result, more wiring connections have been used to accommodate the increasing volume of data being transmitted within devices.

Accordingly, new problems began to emerge as connectors in devices became larger and it became more difficult to bend the connecting cables.

Sony's newly-developed 'single wire interface technology' has achieved bi-directional transmission of several kinds of signals, including video, audio and control signals, by using time division duplex and multiplex. In addition, the DC power is supplied on the same signal cable. Sony's unique encoding technology with DC balance enables both DC power supply and high speed data to be transmitted within a limited frequency bandwidth.

In order to swiftly begin practical implementation of this technology, Sony has teamed up with ROHM Co., Ltd. ('ROHM'), which has a track record in peripheral technologies, for the joint development and technical validation for the analog portion of the test chip.

Hereafter, Sony will grant ROHM a license for the IP of the digital portion of this newly-developed technology in order to advance the development of a single chip which includes both the analog and digital portions.

Main points of development

1. Time division duplex and multiplex have enabled bi-directional transmission of multiple types of data over a single transmission cable

Sony developed a unique time division duplex and multiplex method that enable packets of data, including video (display, camera), audio, and control signals to be transmitted over a single cable. Furthermore, Sony has enabled the bi-directional transmission of different signals, such as display and camera signals, by incorporating a mechanism that retains individual synchronization.

2. Unique multi-level encoding technology has enabled higher transmission rates within the limited signal frequency bandwidth

The newly-developed hardware is composed of (1) a digital portion that performs multi-level encoding, (2) an analog portion that transmits and receives signals, and (3) another portion that combines signals with DC power or separates signals from DC power. A unique multi-level encoding that has no DC component enables both high speed transmission with limited frequency bandwidth and DC power supply on a single common cable.

Sony has demonstrated that high transmission speeds (940Mbps) can be achieved.

Technical specifications (tentative values) of the demonstration system

Transmission signal : video (Display / Camera), audio, control signals

Transmission speed : 940Mbps

Power consumption : 10-80mW (0-940Mbps) during transmission, 0.3mW when on stand-by.

Power supply voltage for analog IC : 1.5V/3.0V

Transmission distance : 60cm

Supplied current value : 600mA

Operating ambient temperature : -20 - +85°C

A comparison with conventional technology

The wiring between the main body of a mobile phone and its display section includes display data, camera data, audio signals, various kinds of sensor data and control data, and a DC power supply. The table below presents a comparison of required wiring for conventional technology, and required wiring for the newly-developed 'single wire interface technology'.

The above estimates assume the following conditions.

Screen display: WVGA resolution

Built-in camera on display side: VGA resolution

Includes audio and DC power wiring.

Has controls for various sensors (two type) such as the touch panel sensors and receives data.

Has 4 key switch data acquisition controls and 2 LED flashing controls.