Archive : 11 November 2008 year
Industry's Only 8-Channel, I2C Switches/Multiplexers with Bus Lockup Detection and Notification
10:31Maxim Integrated Products introduces the MAX7356/MAX7357/MAX7358, 8-channel, I2C switches/multiplexers with bus lockup detection, isolation, and notification. These devices enable a master to isolate slaves that may otherwise have address conflicts and to communicate with each of them individually. The MAX7357 and MAX7358 employ an integrated timer to monitor all extended buses for lockup conditions. Additionally, these two parts can be set to send a "flush-out" sequence on the faulty channel to clear the bus lockup condition. The MAX7356/MAX7357/MAX7358 are ideal for servers, base stations, data storage, and other applications in which multiple I2C devices need to be addressed and controlled.
Fully specified over the -40°C to +85°C extended temperature range, the MAX7356/MAX7357/MAX7358 are available in 24-pin TSSOP and TQFN packages. Prices start at $1.37 (1000-up, FOB USA).
Maxim Integrated Products is a publicly traded company that designs, manufactures, and sells over $2 billion of high-performance semiconductor products annually. It was founded over 25 years ago with the mission to deliver innovative analog and mixed-signal engineering solutions that add value to its customers' products. To date, Maxim has developed over 5900 products serving the industrial, communications, consumer, and computing markets. For more information, go to www.maxim-ic.com.
World’s Best Performing Light Sensor/Proximity Sensor Uses Up To Five Times Less Board Space And Six Times Less Curren
10:28Intersil Corporation a world leader in the design and manufacture of high-performance analog semiconductors, today announced the release of the ISL29015 Ambient and Infrared Light to Digital Converter with IR LED Driver. The device debuts as the world’s best-performing integrated light/proximity sensor.
Featuring the capability to sense ambient light as well as perform infrared sensing, the ISL29015 allows precise backlight and display brightness control while also enabling the applied design to utilize proximity estimates. The device is able to operate under harsh lighting conditions, such as under direct sunlight, or behind very dark glass.
The high integration and ultra-small size (2mm x 2.1mm) of the ISL29015 mean that designers can reduce the required footprint of a proximity sensing solution by a factor of five times versus current discrete solutions. In addition, the ODFN packaging of the ISL29015 is fully transparent, allowing for accurate, uncontaminated reading of ambient light.
The ISL29015 is also extremely power-conscious. When actually sensing ambient light for brightness control and infrared for proximity, the device typically requires a supply current of only 50 microamps. This is up to six times less supply current than needed by other light sensing solutions.
The ISL29015 is the latest in a series of Intersil products that includes both an ambient light sensor and a proximity sensor. The Intersil ISL29020 Low Power, High Sensitivity Light-to-Digital Sensor with I2C Interface was announced earlier this month.
Pricing and Availability
The ISL29015 is available in a 6-lead ODFN package for $1.74 each in 1,00-unit quantities.
For more information on the ISL29015, please go to http://www.intersil.com/cda/deviceinfo/0,1477,ISL29015,0.html
LT3598: LED Driver Drives up to 6 Strings of 10 LEDs Each & Offers 3000:1 True Color PWM Dimming
10:26Linear Technology announces the LT3598, a 45V, 2.5MHz DC/DC boost mode converter designed to operate as a constant current LED driver for up to sixty white LEDs. The LT3598 can drive up to six strings of LEDs, each with up to ten 30mA white LEDs in series while delivering efficiencies up to 90%. Its multichannel capability makes it ideal for medium sized TFT-LCD backlighting applications. Its input voltage range of 3V to 30V makes it ideal for automotive and industrial applications. It offers 1.5% LED current matching to insure uniform brightness of the display. Dimming ratios as high as 3,000:1 can be attained by using True Color PWM™ dimming. A programmable 200kHz to 2.5MHz fixed frequency operation and current mode architecture offers stable operation over a wide range of supply and output voltages while minimizing the size of the external components. Additionally, the switching frequency is synchronizable to an external clock. Its thermally enhanced 4mm x 4mm QFN package offers a very compact solution footprint for LED backlighting applications.
The LT3598 uses a single 1.5A, 45V internal switch to provide a boost mode constant current source. However, even when VIN exceeds VOUT, the LT3598 will continue to regulate the LED current. The internal boost converter uses an adaptive feedback loop to regulate the output voltage slightly higher than the required LED voltage to insure maximum efficiency. If any of the LED strings experiences an open circuit, it will continue to regulate the existing strings and signals the OPENLED alert pin. If higher current LEDs are required, multiple strings can be combined enabling it to drive up to 2 strings of 10 90mA LEDs. Additional features include programmable over voltage protection, LED current derating based on junction temperature and/or LED temperature and output voltage limiting when all LED strings are disconnected.
The LT3598EUF is available from stock in a thermally enhanced 24-lead 4mm x 4mm QFN package, 1,000-piece pricing starts at $2.95 each. An industrial grade version, the LT3598IUF is tested and guaranteed to operate from a -40°C to 125°C operating junction temperature and is priced at $3.39 in 1,000-piece quantities. All versions are available from stock.
Summary of Features: LT 3598
- True Color PWM™ Dimming Delivers Up to 3000:1 Dimming Ratio
- Drives Six Strings of LEDs at Up to 30mA
- 1.5% Accurate LED Current Matching
- Wide Input Voltage Range: 3.2V to 30V
- Output Voltage Up to 44V
- Regulates Current Even When VIN > VOUT
- Disconnects LEDs in Shutdown
- Programmable Open LED Protection (Regulated)
- OPENLED Alert Pin
- Programmable LED Current Derating
- Adjustable Frequency: 200kHz to 2.5MHz
- Synchronizable to an External Clock
- Parallel Channels for Higher Current per LED String
- Thermally Enhanced 4mm × 4mm QFN Package
IR’s Control ICs for Energy-Efficient Fluorescent Ballasts Slash Component Count; Increase Reliability and Performance
10:20International Rectifier a world leader in power management technology, today introduced the IRS2530D and IRS2158D 600V control ICs for energy-efficient dimming fluorescent lighting ballast applications.
The IRS2530D DIM8™ is a unique linear dimming ballast control IC with half-bridge driver in a compact 8-pin form factor. The new device provides a competitive solution to replace inefficient incandescent bulbs in multi-level and three-way compact fluorescent lighting (CFL) applications. Requiring only several small external components, the IRS2530D significantly simplifies and shrinks circuit design and delivers a dimming system performance of up to 10 percent for compact fluorescent lamps as well as linear ballasts.
The IRS2158D 16-pin fluorescent dimming ballast control IC with half-bridge driver is designed for applications requiring dimming performance below 10 percent. Comprehensive protection features such as protection from failure of a lamp to strike, filament failures and end-of-life protection are offered making the device well suited for thin lamps including the increasingly popular T5 lamp.
“These innovative new devices add to IR’s rich portfolio of energy-efficient products. With the opportunity to save up to 30 percent of energy compared to non-dimming lighting, designers are seeking to create new dimming product lines using several different control methods. With a high level of integration and protection features, the new control ICs provide the small form factor, functionality and performance required while reducing part count and simplifying design,” said Tom Ribarich, IR’s director, Lighting Systems and Applications.
IRS2530D DIM8™ Technical Data
The IRS2530D DIM8™ control IC features IR’s patented ballast and high-voltage technologies. A single high-voltage pin senses the half-bridge current and voltage to perform necessary ballast protection functions. The DC dim input voltage reference and AC lamp current feedback are combined allowing a single pin to be used for dimming. These high-voltage control algorithms coupled with a simple dimming method in a single 8-pin IC result in a significantly reduced component count, increased reliability and reduced design cycle time, while maintaining high dimming ballast system performance. The IRS2530D also features an internal non-ZVS protection and internal crest factor protection to prevent lamp failure damaging the ballast.
IRS2158D Technical Data
The IRS2158D is a fully integrated, fully protected 600V ballast control IC designed to drive a wide variety of fluorescent lamps. The device’s features include programmable half-bridge over-current protection, programmable pre-heat and run frequencies, programmable preheat time and deadtime, closed-loop half-bridge ignition current regulation, programmable end-of-life protection, brownout protection and low input offset operational amplifier for dimming, current or power control. In addition, the new device features end-of-life window comparator pin and internal 60-event current sense up/down fault counter to accommodate T5 lamp and multi-lamp ballasts.
Specifications
| Programmability | IRS2530D | IRS2158D |
|---|---|---|
| Preheat Time | Yes | Yes |
| Preheat Frequency | - | Yes |
| Closed Loop Ignition Current | - | Yes |
| Run Frequency | Yes | Yes |
| Deadtime | - | Yes |
| Features | IRS2530D | IRS2158D |
| Fixed Deadtime | 2.0 µs | Programmable |
| Failure to Strike | On Over Current | Yes |
| Open Filament | On Over Current | Yes |
| Brownout Protection | with non-ZVS | Yes |
| Shutdown Pin | - | Yes |
| Fault Counter | - | Yes |
| End-of-Life Protection | - | Yes |
| Integration | IRS2530D | IRS2158D |
| Bootstrap Diode | Yes | Yes |
| Crest Factor Over Current Protection | Yes | - |
| Adaptive Non-ZVS Protection | Yes | - |
| Dimming | IRS2530D | IRS2158D |
| Minimum Dimming Level | 10% | < 10% |
| Package | IRS2530D | IRS2158D |
| DIP & SOIC | 8 pin | 16 pin |
The IRPLDIM4E, IRPLDIM5E, IRPLCFL8U reference designs, featuring the IRS2530D are available in addition to the IRPLDIM3 reference design which features the IRS2158D.
Availability and Pricing
Available in an 8-lead DIP or 8-lead SOIC package, pricing for the IRS2530D begins at US $1.09 in 10,000-unit quantities. The IRS2158D is available in16-pin PDIP and 16-pin narrow body SOIC packages with pricing beginning at US $1.29 each in 10,000-unit quantities. Pricing for the IRPLDIM4E, IRPLDIM5E and IRPLCFL8U reference designs is US $99 per kit, and pricing for the IRPLDIM3 is US $150 per kit. Production orders are available immediately. The devices are RoHS compliant and prices are subject to change.
From: http://www.irf.com
Fairchild Semiconductor's 8A Buck Regulator Achieves 95 Percent Peak Efficiency in Servers, Workstations and Distributed POL Applications
10:16Fairchild Semiconductor enables power designers to achieve higher output current and high efficiency using less PCB space with its TinyBuckTM DC-DC regulator. The FAN2108 is an 8A, fully integrated, synchronous buck converter that drives efficiency over a wide input voltage range (3V to 24V) for applications such as set-top boxes, graphic cards, point of load (POL) and industrial power network devices. Alternate solutions achieve efficiency by using additional discrete components or require significant board space – lengthening design time and increasing the size of the end application. The TinyBuck™ integrates the controller, MOSFETs, and boot diode into a slim 5mm x 6mm MLP footprint - making it the industry’s smallest 8A solution. The FAN2108 has been designed with Fairchild’s PowerTrench® MOSFET process with extremely low Figure of Merit (FOM) to reduce conduction and switching losses. At 12V input and 8A load current, the FAN2108 delivers 92 percent efficiency at 3.3V output and 87 percent efficiency at 1.8V output. At 5V input and 3.3V output, this device achieves a peak efficiency of 95 percent.
The FAN2108 offers multiple protection features such as over-voltage, over-current, short-circuit and over-temperature. It also features pre-bias startup, allowing the regulator to start-up on a pre-biased output and ensures that the output is not discharged during the soft-start cycle, protecting system ICs from damage.
Fairchild’s TinyBuck regulator is part of a family of all-in-one regulators that improve efficiency, while simplifying designs. This family includes a 3A version, the FAN2103 that offers 95 percent efficiency for graphic cards, set-top boxes, servers and point of load (POL) applications.
The FAN2108 utilizes lead-free (Pb-free) terminals and has been characterized for moisture sensitivity in accordance with the Pb-free reflow requirements of the joint IPC/JEDEC standard J-STD-020. All of Fairchild's products are designed to meet the requirements of the European Union's Directive on the restriction of the use of certain substances (RoHS).
Price (each, 1000 pcs.): US $1.41
Availability: Samples available now
Delivery: 6 to 8 weeks ARO
Contact Information:
To contact Fairchild Semiconductor about this product, please go to: www.fairchildsemi.com/cf/sales_contacts/.
For information on other products, design tools and sales contacts, please visit: www.fairchildsemi.com.
From: http://fairchildsemi.com