A recent CNN story called “Converting Gas-Powered Cars to Electric” sparked a round of e-mails among us Electronic Design editors. The story specifically described a man who ripped the engine out of his Chevy S-10 pickup and installed an electric motor, reminding me of a conversation I had yesterday with Dave, my barber. Dave drives this brobdinagian pickup camper, and we were talking about what’s under its hood.

Hybrids and electric cars may get all the buzz these days, but what if you could leave the grid entirely? That may not be as far-fetched as you think, based on the results of the 2008 North American Solar Challenge. Last month, 15 teams and their sun-powered cars charged 2400 miles across the continent to test the technology’s viability.

“The meter’s running backwards!” I wrote that line in August 2006, quoting my wife Vicky, who was entranced by the most visible manifestation of what our just completed rooftop grid-connected solar system was achieving (“A Solar Story,” ED Online 13242). While that column covered the technical details of its installation, this story is about the economic advantages we’ve seen since then.

Chinese automobile manufacturer ChangAn Inc. has equipped a number of its vehicles in the Jiexun series with a mild-hybrid engine, using Infineon Technologies’ power electronics. The hybrid electric vehicles (HEVs) will be used as taxis for athletes and spectators during the Olympic Games in Beijing.

At the Semicon West convention held earlier this month, several representatives from Darnell Group held a panel discussion on the energy harvesting and its forthcoming mass appeal. Speakers included Jeff Shepard, president of Darnell, Jerry ruddle, executive vice president with Advanced Cerametrics and Solicore’s vice president, Jarreth Solomon.

A few engineers were having a debate. According to all the books, some of them said, op amps are supposed to have zero output impedance, or very low. That means the output voltage wonâ??t change, just in case the output current changes. Some older op amps had an output impedance of 600 ? or 50 ?. So, the gain of the amplifier wonâ??t change just because the load changes. That must be good. But a couple of other engineers pointed out that many modern op...

Power-added efficiency (PAE) is the ratio of the difference of the power gain of an RF power amp to the dc power that amp consumes. In commercial wireless systems at 175 and 500 MHz in cell phones at 800 and 900 MHz, it’s customary to use two MOSFET stages in the final output, running off a 3.6-V rail. For those typical applications, Renesas has applied a new process technology to boost PAE. The n-channel first-stage RQA0014 has 55% higher PAE than...

HI BOB, I am trying to build a test circuit that will produce a pulse current from a capacitor. My target is around 200 A at 100 ms. Is this possible? We have an instrument called a PVI that does the same only at lower current and at shorter duration, but I don’t know how it is being controlled. I hope you can give me advice or a basic control circuit that I can start working on. –ROMMEL C. VILLON HELLO, MR. VILLON, You...

By moving digital feedback and PMBus control upstream from point-of-load (POL) dc-dc converters in intermediate-bus-architecture (IBA) power-distribution schemes, Ericsson Power Modules may have sidestepped a patent problem that has all but dried up new IBA developments. The brains are now in the formerly “dumb” bricks that step down 48 V dc to whatever the POLs need. In addition to jumpstarting a stalled digital IBA, Ericsson’s engineers have improved system...

Designers can deliver up to 10 Gbits/s of Ethernet over 30 m of copper cable thanks to a pair of developments from Phyworks Ltd. The 24 AWG twin-ax cable is terminated in SFP+ connector assemblies that employ the company’s PHY2060 active equalizer, CDR, and retimer IC (see the figure). The PHY2060 was originally developed for optical-fiber applications, but it adapts well to the copper...

Due to their light output and long life, high-brightness LEDs are well-suited for use in flashlights. Typically, the LEDs are driven with a constant current. So when the battery voltage drops, the flashlight just stops working. In some situations, this could be dangerous. It would be nice to have a flashlight that would automatically dim when the battery voltage drops. Just like a traditional flashlight, it would indicate a low-battery condition and...

This design shows how we combined four 36-V DeWalt DC9360 nanophosphate battery packs in a series-parallel configuration to create a robust, high-energy power source. Originally intended for the prototype Neodymics Cyclemotor electric bicycle kit, this power source may be used in other applications. Output power was at least 1.6 kW at 66 V, energy capacity was about 300 W-hr, and recharge time was one hour. Also, the claimed cycle life exceeds 2000. The...

This idea shows how to monitor input voltage and current consumption for telecommunications equipment powered by two independent feeds: -48 V (A) and -48 V (B). Each feed supplies at least -42.5 V to -56.5 V, and for redundancy the feeds are ORed on the module. For maintenance and support purposes, it’s important to monitor input voltage, the feeds’ presence, and the module’s power consumption. ...

High-brightness LEDs (HBLEDs) are making inroads into more traditional lighting applications that include a dc distribution system (for example, 24-V MR-16 track lights). HBLEDs are more efficient, and they have a potentially longer lifespan than do halogen or xenon lamps. Because hysteretic controllers are inexpensive, simplify lighting designs, and require no compensation networks, they’re well-suited for driving HBLEDs....

The converter described below, based on a silicon bipolarjunction transistor (BJT), can operate at as low as 250 mV, which is probably a record for a converter not based on a JFET or germanium transistor. How is this possible? The VBE threshold is not clear-cut, depending on current density and other factors. But 250 mV is way below the lowest accepted values. There has to be a trick and there is, sort of. The big difficulty is in the starting....