Feature demand strains portable memory design
Teardown 1/30/2006 Post a comment
Handset models are changing every year as designers strive to strike a balance between what end users want and what can actually be designed in. Many trade-offs must be considered, including performance and features vs. price, size and battery life.
Minimizing Servoamplifier-Sourced Noise
Design How-To 1/17/2006 Post a comment
PWM servo amplifiers energize servo motors with current waveforms under control of fast-rise voltage pulses. The faster the rise rate of the drive pulses, the lower the energy dissipation in the servo amplifier's MOSFET or IGBT power semiconductors, and amplifier efficiencies in 95% region become possible. Unfortunately, there's a rise-rate tradeoff: the faster the rise rate, the more likely is the amplifier to source noise currents that interfere with neighboring circuits.