Tuesday, September 27, 2011

High Efficiency Step Down Isolated Supply

60W AC-DC adapter, synchronous rectification, fixed frequency current mode PWM controller. Very Low Quiescent Burden, Efficiency above 85%. That's Green.

STMicroelectronics - EVALSTSR30-60W. Synchronous rectification using L6668 and STSR30.

EVALSTSR30-60W: 60W AC-DC adapter

EVALSTSR30-60W: 60W AC-DC adapter

The converter works in both Continuous and Discontinuous conduction mode depending on the input voltage (the circuit has a wide input voltage range) and the output load. The 68-kHz switching frequency provides a good compromise between the transformer size and the harmonics of the switching frequency, optimizing input filter.

The input section includes protection elements (varistor, fuse and NTC for inrush current limiting), a standard Pi-filter for EMC suppression, a bridge and an electrolytic bulk capacitor as the front-end AC-DC converter. The transformer is a layer type, uses a standard ETD34 ferrite core and is designed to have a reflected voltage of 95V. The power MOS is a 700V - 1Ω and a transil clamp network is used for leakage inductance demagnetization.

From STMicroelectronics

Friday, September 23, 2011

Solar Cell Voltage Booster with MAX856

This circuit generates an usable power 5V good for charging portables. Even lighting a White LED Array.

A Supercap Flywheel may be good addition to this, these kind of chips can also add supercap power management, as it will take a lot of current to charge up. This will keep power flowing when the sun goes behind the clouds.

Harnessing Solar Power with Smart Power-Conversion Techniques

"Obtaining all the available energy from a solar panel requires a switch-mode step-up or -down converter and battery charger, in addition to the battery. The converter must ensure that every bit of energy taken from the solar panel is efficiently stored in the battery for future use."

Solar Cell Voltage Booster with MAX856.

The MAX856-MAX859 are high-efficiency, CMOS, step-up, DC-DC switching regulators for small, low input voltage or battery-powered systems.

Thursday, September 22, 2011

PC-Based Logic Analyzer - Intronix

The LogicPort provides 34 channels sampled at 500MHz. This includes two state-clock inputs which function as normal sampled channels in timing-mode. The LogicPort is controlled and powered via your PC's USB 1.1 or 2.0 port for the ultimate in convenience and portability.

PC-Based Logic Analyzer - Intronix

PC-Based Logic Analyzer - Intronix

The LogicPort's software includes interpreters for CAN, I2C, Synchronous Serial (SPI) and Asynchronous Serial (RS232) protocols. Its Synchronous Serial interpreter is very flexible and interprets 3-Wire, Microwire, PS/2 and other proprietary protocols in addition to SPI.

Feaures Include
  • Real-Time Sample Compression
  • 500MHz Timing-Mode (Internal Clock)
  • 200MHz State-Mode (External Clock)
  • Advanced Multi-Level Triggering
  • Built-in 300MHz Frequency Counter
  • CAN, I2C, SPI and RS232 Interpreters
Intronix is developing high-performance PC-based test instruments. They started as a ATE solutions provider. Automated test equipment and systems (ATE) are PC based Advanced T&M Interfaces.

Intronix Test Instruments, Inc.
2630 E. Mohawk Ln. Unit 144, Phoenix, Arizona 85050, USA.