Semiconductor Corp.'s stereo analog
with integrated Class G headphone amplifier and automatic level control (ALC)
is for smartphones and feature phones. The PowerWise LM49251's Class G
headphone amp reduces the supply voltage to lower power consumption and extend
audio (MP3, movies, etc.) playback time. The loudspeaker's ALC provides
designers with options to control audio distortion levels and prevent speaker
National's LM49251stereo analog subsystem combines a 1.4W Class
D speaker amplifier, 20 mW Class G headphone amplifier and ALC in a 2.55 by
3.02 mm package. The LM49251 offers low power consumption, consuming less than
7 mA of quiescent current at 3.3V for the loudspeaker and headphone. The
LM49251's ALC feature provides designers with a programmable output power
limiter for speaker protection and clip level select.
Offered in a 30-bump micro SMD package, the LM49251 provides enhanced Emission Suppression
(E2S) and a Class D amplifier featuring a patented, ultra-low EMI pulse-width
modulation (PWM) architecture that significantly reduces RF emissions while
preserving audio quality. The LM49251's Class G headphone architecture
significantly increases audio playback time with its adaptive power supply
approach, enabling low supply rails.
no-clip ALC feature prevents distortion as battery voltages drop, allowing
small signals to be amplified at high gains while preventing clipping of
high-level signals. Its multiple inputs provide configurability for addressing
different system requirements, and the LM49251's mode selection, shutdown and
volume are controlled through an I2C compatible interface. The IC's
click-and-pop suppression eliminates audible transients on power up and during
introduced the LM49153 mono audio subsystem,
which includes the same features as the LM49251, while integrating noise gate
functionality onto the Class D amplifier. The noise gate feature prevents noise
from being amplified when the volume is turned up. The LM49153 is offered in a
25-bump, 2.30 by 2.42 mm, micro SMD package.
Some humanoid walking robots are also good at running, balancing, and coordinated movements in group settings. Several of our sports robots have won regional or worldwide acclaim in the RoboCup soccer World Cup, or FIRST Robotics competitions. Others include the world's first hockey-playing robot and a trash-talking Scrabble player.
The DDV-IP is a two-wheeled self-balancing robot that can deliver cold beverages to thirsty folks on hot summer days. A wireless RF remote enables manual control of the device beyond the act of self-balancing. All of the features of the DDV-IP result in an effective delivery vehicle while providing entertainment to the user.
Eric Doster of iFixit talks about the most surprising aspect of the Microsoft Surface Pro 3 teardown. In a presentation at Medical Design & Manufacturing Midwest, iFixit gave the Surface Pro 3 a score of one (out of a possible 10) for repairability.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.