A record 78,000 attendees were reported at the Electronica event held last week in Munich and many power component vendors took advantage of this massive industry gathering to showcase their latest wares. Several vendors used the occasion to launch new power ICs and modules, passives, and other components. Among the power components unveiled at Electronica were second-generation, point-of-load converters from Enpirion; power management chips and LED drivers from Advanced Analogic Technologies, power and current-sense resistors from TT Electronics, and mini solid-state relays from Avago Technologies.
Enpirion (www.enpirion.com), maker of IC-style dc-dc converters with inductors in package, announced the release of its second-generation products with 3-A and 6-A load current ratings. According to the vendor, the 3-A EN533x and the 6-A EN536x synchronous buck converters occupy 25% less pc-board area than the company first-generation point-of-load converters (POLs). In addition, these second-generation parts achieve as much as 5% better efficiency than the first-generation converters thanks to optimization of on-chip MOSFET switches. These QFN-packaged parts also offer enhanced thermal performance, which eliminates the need for thermal derating or forced-air cooling at ambients up to 85°C.
According to the vendor, the second-generation converters produce much smaller designs than competing POLs. In addition, Enpirion claims an additional advantage versus conventional regulators or controller-plus-switch designs—lower ripple and noise on the output. As a result of this quieter performance, the EN533x and EN536x can power sensitive CMOS circuits designed in 95-nm (and finer) processes without requiring significant increases in output capacitance. (For pricing on this and other parts mentioned in this article, see the table below.)
Advanced Analogic Technologies (www.analogictech.com), announced the AAT2550, a highly integrated power management IC for smart phones, portable media/music players, and other handheld devices. Targeted at systems powered by single-cell Li-ion batteries rated up to 1500 mAh, this chip saves pc-board space by combining a 1-A battery charger with two 600-mA stepdown converters in a 4-mm x 4-mm QFN. This device features a digital thermal control loop in the battery charger, which automatically reduces charge current when the demand on the power system exceeds its thermal limits.
For systems that require charging from either ac or USB sources, AnalogicTech unveiled the AAT2551 SystemPower IC. Similar to the AAT2550, this device features a 1-A charger and two 600-mA buck converters. However, the charger in the AAT2551 offers dual-path ac adapter and USB charging. The USB path offers two user-programmable charge currents to support USB low and high charge levels. The charger in the AAT2551 also adds AnalogicTech’s charge reduction function, which automatically reduces charge current just enough to preserve the integrity of the USB host voltage. The company also announced the AAT2830/31 Total Display Solution for handsets and other portable systems operating off a single Li-ion cell. Built around a high efficiency, tri-mode charge pump, these chips deliver up to 600 mA of current for the growing array of lighting applications in portable systems including main- and sub-display backlighting, camera flash, and RGB or auxiliary status lighting. Individual driving circuits for each function are controlled by AnalogicTech’s single-wire serial digital interface.
Avago Technologies (www.avagotech.com/optocouplers) unveiled three families of solid state relays (SSRs) with what is claimed to be the industry’s highest insulation voltage in a miniature SO-4 package. These relays are also said to offer the industry’s fastest switching speed (less than 1 ms) at the 1-A rating.
Specifying 3.75 kV of insulation protection, Avago’s expanded family of SSRs with MOSFET outputs enables designers to improve power efficiency, performance and reliability in low- and high-current circuits often found in telecommunications, consumer electronics, automotive and industrial applications.
Avago’s ASSR-1510/1511/1520 family of 60-V, 1-A, 0.5-Ω relays provides the fastest switching speed available among 1-A SSRs, says the vendor. Along with the ASSR-15xx, the ASSR-4110/4120 family of 400-V, 0.12-A, 25-Ω relays and the ASSR-1410/1420 family of 60-V, 0.6-A, 1-Ω relays are available as 1 Form A (single-channel) SSRs with MOSFET outputs in SO-4 packages and as 2 Form A (dual-channel) SSRs in DIP-8 packages. Each product family features qualified performance across the -40ºC to +85ºC temperature range, a switching speed of less than 1 ms and transient immunity greater than 1 kV/µs.
TT electronics introduced several resistive components targeting power applications. The company’s BI Technologies SMT Division (www.bitechnologies.com/products/passive.htm.) debuted a 75-W nonmolded power resistor that exploits three methods of power dissipation to achieve exception power handling. Housed in a TO-220 opened-screened-substrate package, the BHP75 Series resistor features an insulated tapered venturi bonded to the substrate for maximum heat dissipation. Typical applications include switch-mode power supplies, motor control and drive circuits, inverters and industrial power equipment.
“The chimney-shaped tapered venturi is attached to the ceramic substrate and convection forces hot air up the “neck” of the chimney and away from the resistor face of the component,” says Jim Rieley, Sales Director for BI Technologies’ SMT Division. “The power resistor utilizes all three methods of heat dissipation, including conduction through the heat sink tab, radiation from the resistor surface, and convection through the venturi element.”
Meanwhile, the company’s IRC Wire and Film Technologies Division (www.irctt.com) announced a family of power MELF resistors with ratings up to 2 W for use in harsh environments. Consisting of the CHP, SMC and HSF series resistors, the devices in the power MELF family all use IRC’s metal glaze resistive element on ceramic substrates.
According to David Winkler, product manager for IRC’s Wire and Film Technologies Division, the resistors in the power MELF family provide excellent thermal compliance as well as a variety of surge capabilities. “The rugged CHP and SMC Series resistors are rated up to 2 W and provide maximum thermal compliance, while the HSF Series resistors offer as much as three times the surge rating of standard CHP resistors, which equates to up to 10 times the surge rating of similar-sized flat thick-film chip resistors,” said Winkler. “The range of capabilities allows customers to select the best device to provide stable performance in harsh environment applications.”
The IRC Wire and Film Technologies Division also introduced a wider version of their open-air current sense resistor with a higher power rating than conventional metal element resistive devices. Specified for automotive applications, the OARS-XP series resistor offers exceptional TCR ratings and superior thermal compliance. The OARS-XP Series resistor is being specified for applications involving window lift motors, fuel pump systems, seat belt pretensioners, and pulse width modulator feedback.
Table. Pricing and Availability
Enpirion’s EN533x and EN536x synchronous buck converters
EN533x, $2.94 and EN536x, $4.36
Advanced Analogic Technologies’ AAT2550 portable power management IC
AAT2550, $2.19 each
Advanced Analogic Technologies’ AAT2830/31 Total Display Solution for handsets and other portable systems
Sampling in December 2006
Avago Technologies’ three families of solid state relays (SSRs)
ASSR-1410/1420 begins at $1.48 (SO-4) and $2.49 (DIP-8); ASSR-4110/4120 begins at $1.20 (SO-4) and $2.31 (DIP-8); ASSR-1510/1511/1520 begins at $2.41 (SO-4), $2.22 (DIP-6) and $4.44 (DIP-8); all in quantities of 10,000.
Contact the vendor
TT electronics BI Technologies SMT Division’s BHP75 Series 75-W resistor
$1.80 each typical in medium volumes.
Samples are available immediately. Production quantity lead time is from stock to 6 weeks.
TT electronics IRC Wire and Film Technologies Division’s power MELF resistors
Approximately $0.18 typical in quantities of 10,000.
Available now. Lead-time is from stock to 4 to 6 weeks.
TT electronics IRC Wire and Film Technologies Division’s OARS-XP series current sense resistor
$0.40 typical in 1,500 piece per reel quantities.
Available now. Lead time is 14 weeks.
*In quantities of 1000, unless otherwise stated