Ultra low power audio codec (Ou Sheng)

Wolfson Microelectronics has announced the world's leading ultra-low power codec WM8904 with Class W headphones and line drivers designed to provide low power consumption and significantly extend playback time, such as media players. Portable applications such as headsets, voice recorders and multimedia phones.

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The WM8904 is one of Wolfson's next-generation ultra-low-power audio device family that delivers high-performance audio and market-leading low power consumption in an ultra-thin, low-profile form factor.

The WM8904 integrates Wolfson's Class W amplifier technology, which intelligently tracks actual music signal levels and uses an adaptive dual-drive charge pump to optimize power dissipation. The grounded reference output design also eliminates the reliance on large DC-blocking headphone capacitors, improving bass response and saving the printed circuit board (PCB) space and the overall bill of materials (BOM) of the audio subsystem.

The WM8904 is also equipped with Wolfson's innovative SmartDACTM technology, a unique low-power DAC capacitor switch architecture that allows the DAC to convert to only 4mW into headphones and up to 30mW per channel for headphone loads.

Its audio performance is further enhanced by the integration of Wolfson's innovative SilentSwitchTM technology, which enhances the “pop&click” suppression capability by integrating complex clamp and sequencer circuits. With this feature, the output is held to ground by clamping during power-up/shutdown and mute/un-silence, and unwanted noise at the headphone amplifier and line output can be effectively suppressed. By enabling/disabling multiple components of the WM8904 with a built-in control write sequencer with programmable delay time, the “beep” can be significantly reduced and can be greatly accelerated by reducing the development time of the driver software Time to market.

The WM8904 includes an advanced dynamic range controller (DRC) that improves audio performance. The DRC can be flexibly configured in the recording mode to optimize the recording quality while minimizing distortion of the recording signal. Wolfson also uses the “quick release” quick release feature to improve the clarity of the recording in the presence of large impulse noise. This function ensures that the noise event operated by the user does not obscure the recording signal at all. In playback mode, the DRC maximizes the volume of the output signal and boosts the perceived loudness of the audio data.

Wolfson's innovative RetuneTM Mobile Parametric Equalizer is powerful enough to ensure that system designers can accurately customize the output signal path and optimize the performance of speakers or other transducers. Various line inputs, including digital and analog microphone inputs, are supported with bypass and line outputs for Class W headphones. Available in two small packages, the WM8904 is available in an ultra-compact 2.6 x 2.5mm chip scale package.

"The WM8904 offers ultra-low power consumption in all modes. Wolfson focuses on battery life while running the actual audio signal and guarantees that its high fidelity audio performance is not compromised," said Duncan Macadie, manager of Low Power Audio Lines at Wolfson. Capabilities are second to none in the industry. The WM8904 offers the best combination of audio performance, power consumption, package size and overall solution cost, making it ideal for a wide range of portable multimedia applications."

Samples of the WM8904 are available now in a 32-pin 4x4mm QFN package and a 36-ball CSP package.

The WM8904 Customer Evaluation Board and its Wolfson Interactive Installation and Configuration Environment Software (WISCETM) can be used to support device evaluation and development. WISCE can be connected to the evaluation version via USB, providing a unique interactive register mapping interface that supports unprecedented device setup control and supervision. Texas Instruments (TI) announced today that it will showcase the industry's first contactless charging evaluation kit at the 2010 International Consumer Electronics Show (CES). The bqTESLATM Contactless Charge Evaluation Kit is a high-performance, easy-to-use development kit based on Fulton Innovation CoupledTM intelligent wireless power technology that meets the design needs of low-power, contactless charging solutions. The kit includes a single-channel transmitter, direct-charge receiver, and associated magnetic components to help designers accelerate the development of wireless charging capabilities such as smartphones, MP3 players, netbooks, and global positioning systems (GPS) ) Terminal applications such as units.

bqTESLA enables true “plug and play” design without the need for additional software development. The reference guides recommend coil solutions for designers to customize the receiver. In addition, the bqTESLA evaluation kit helps designers develop systems that are compatible with future Qi standards being developed by the Wireless Power Consortium.

The main components of the bqTESLA contactless charging evaluation kit:

- transmitter evaluation board;
- receiver evaluation board;
- transmitter coil, shield and magnetic components;
- receiver coils, shielding and magnetic components;
- Technical documentation
Designers can order complete kits or order a single transmitter and receiver evaluation board. The kit is expected to be available by the end of the first quarter of 2010.

Learn about the bqTESLA Contactless Charge Evaluation Kit:

Dc Motor

A DC motor is any of a class of rotary electrical machines that converts direct current electrical energy into mechanical energy. The most common types rely on the forces produced by magnetic fields. Nearly all types of DC motors have some internal mechanism, either electromechanical or electronic, to periodically change the direction of current flow in part of the motor.

DC motors were the first type widely used, since they could be powered from existing direct-current lighting power distribution systems. A DC motor's speed can be controlled over a wide range, using either a variable supply voltage or by changing the strength of current in its field windings. Small DC motors are used in tools, toys, and appliances. The universal motor can operate on direct current but is a lightweight motor used for portable power tools and appliances. Larger DC motors are used in propulsion of electric vehicles, elevator and hoists, or in drives for steel rolling mills.

Dc motor areas of application: smart home field, robotics, precision medical equipment industry, automotive drive field, electronic products and personal care equipment

Application of the product:

Features: high torque, low noise, small volume, light weight, easy to use, running constant speed, etc., can also be matched with various gearboxes to change the output speed and torque.

Features: small volume, fast speed, stable performance, low price, good speed regulation.

Method of use: the best stable in horizontal plane, installed on the dc motor output shaft parts, cannot use a hammer to knock, knock prone to press into the dc motor drive, may cause damage to internal components, and cannot be used in the case of blocked.

Operating temperature range:

DC motor should be used at a temperature of -10~60℃.

The figures stated in the catalog specifications are based on use at ordinary room temperature catalog specifications re based on use at ordinary room temperature (approximately20~25℃.

If a geared motor is used outside the prescribed temperature range,the grease on the gearhead area will become unable to function normally and the motor will become unable to start.Depending on the temperature conditions ,it may be possible to deal with them by changing the grease of the motor's parts.Please feel free to consult with us about this.

Storage temperature range:

DC motor should be stored ta a temperature of -15~65℃.

In case of storage outside this range,the grease on the gearhead area will become unable to function normally and the motor will become unable to start.

Service life:

●Use with a load that exceeds the rated torque

●Frequent starting

●Momentary reversals of turning direction

●Impact loads

●Long-term continuous operation

●Forced turning using the output shaft

●Use in which the permitted overhang load or the permitted thrust load is exceeded

●A pulse drive ,e.g.,a short break,counter electromotive force,PWM control

●Use of a voltage that is nonstandard as regards the rated voltage

●Use outside the prescribed temperature or relative-humidity range,or in a special environment.

●Please consult with us about these or any other conditions of use that may apply,so that we can be sure that you select the most appropriate model.

when it come to volume production,we're a major player as well .each month,we rurn out 600000 units,all of which are compliant with the rohs directive.Have any questions or special needed, please contact us, we have the engineer group and best sales department to service to you Looking forward to your inquiry. Welcome to our factory.

Dc Motor,Small Dc Motor,Mini Dc Motor,Robot Dc Motor,Dc Motor With Gearbox

Shenzhen Shunchang Motor Co., LTD. , https://www.scgearmotor.com