•UltraFast™ Digitally Programmable 5A LDO
LINEAR TECHNOLOGY Corporation announces the LT3071, the second in a family of digitally programmable linear regulators with the lowest dropout voltage, lowest noise and fastest transient response of any monolithic 5A LDO currently available. Dropout voltage at 5A is an ultralow 85mV. Output voltage noise at 5A is only 25µVRMS over a 10Hz to 100kHz bandwidth. The LT3071's 1MHz unity gain bandwidth, coupled with its minimum 15µF ceramic output capacitance, provides a mere 30mV of overshoot/undershoot in response to a fast 4.5A output load step, saving significant bulk capacitance, space and cost. The LT3071 is ideal for efficiently powering low voltage, high current devices such as FPGAs, DSPs, ASICs, microprocessors, sensitive communication supplies, server/storage devices, and post-buck regulation applications. The LT3071's output voltage is digitally programmable from 0.8V to 1.8V in 50mV increments. Accuracy is tightly specified at ±1% over line, load and temperature. An analog output margining feature could adjust system output voltage over a continuous ±10% range, advantageous during system development debug. A PowerGood flag indicates if output voltage is in regulation or if the device is in UVLO, and the flag also provides an early warning indication of a thermal fault. An output current monitor sources a scaled dynamic representation of output current (IOUT/2500) that can be measured directly or terminated with a resistor and converted to voltage, allowing load conditions or power to be calculated. The LT3071's input supply voltage range is 0.95V to 3.0V, and its bias supply voltage ranges from 2.2V to 3.6V. The bias supply provides gate drive to the internal NMOS pass device. Multiple LT3071 devices can be easily paralleled for higher output current and to spread heat across a circuit board. A tracking feature can control a buck regulator powering the LT3071's input. This tracking function drives the upstream buck regulator to maintain the LT3071's input voltage at VOUT + 300mV, minimizing power dissipation. If output voltage is dynamically changed, the tracking function automatically adjusts the output voltage of the buck regulator to maintain efficiency. Internal protection circuitry includes UVLO, reverse-current protection, precision current limiting with power foldback and thermal shutdown with hysteresis.
The LT3071 is offered in a thermally enhanced, low profile (0.75mm) 28-lead 4mm × 5mm QFN package, and both E and I grades operate from -40°C to +125°C junction temperature range. 1,000-piece pricing starts at $4.20 and $4.80 each, respectively.
•MicroPMIC for Multimedia Application Processors
MAXIM INTEGRATED Products introduces the MAX8893, a highly integrated microPMIC for multimedia application processors. This device includes one high-efficiency step-down converter, three low-noise LDOs, two low-supply-current LDOs, one low-on-resistance load switch, and one Hi-Speed USB switch-all in a 2.5mm × 3.0mm, 30-bump wafer-level package (WLP). This integration saves space and cost without sacrificing design flexibility. All regulators and switches have individual enable pins that allow designers to turn on/off different functional blocks to save power and extend battery life. Its high level of integration and functional block enable control make the MAX8893 a complete power-management solution for multimedia application processors in portable devices such as cellular handsets. For enhanced performance, the integrated LDOs provide low 45microVRMS output noise and a low dropout of only 100mV at 100mA (LDOs 1,4 and 5), as well as a very low, 21microamp ground current for longer battery life. These LDOs have programmable output voltages for ease of use in numerous applications. The 4MHz buck converter allows ultra-small external components and features dynamic voltage-scaling (DVS) control of the ramp rate (from 1mV/microsecond to 12mV/microsecond). The load switch features ultra-low on-resistance (50milliohm, min) and operates from an input voltage of 0.8V to 2.4V. Pricing for the MAX8993 starts at $1.95 (1000-up, FOB USA). A user-friendly evaluation kit is available to speed designs.
•Speed Controller for Brushless DC Motors With Hall Sensors
THE MAXON motor DEC module 50/5 controller is a digital amplifier module with speed controller to control brushless DC motors with Hall sensors rated up to 250 watts. The motor speed controller works with an operating voltage of up to 50 VDC, an output current of 5 A in continuous operation and its usage is flexible, versatile and highly efficient. The controller offers a large number of inputs and outputs, including enable, speed ranges, speed monitor, direction of rotation presetting, operating status, and current limiting. The controller incorporates internal protection from overcurrent, undervoltage and overvoltage, thermal overloads, and short circuits. The all-in-one controller , with an extremely high power density of 250-watt continuous output power at 12 cm2 (3 × 4 cm), may be seamlessly integrated into complex applications with minimum effort.
Fall River, MA
•Low Resistance, High Stability Chip Resistor
PROVIDING DESIGN engineers with a high power, low resistance device for current sensing applications, TT electronics IRC has developed a highly stable low resistance chip resistor. Designated the LRF3W-MIL Series, the chip resistors utilize high reliability thick film materials and are available with screening to MIL-PRF-55342 or customer drawing. The chip resistor package includes an uninterrupted 2-pad termination on the long sides of the resistor, maximizing thermal transfer and improving reliability. “The LRF3W-MIL resistors combine high power, excellent stability, and extremely low resistance values in a compact 1225 package,” said Gary Bleasdell, director of TT electronics IRC's thick film business unit. “This chip resistor is an ideal solution for high current sensing applications in demanding applications such as the military and aerospace arenas.” Resistance for the LRF3W-MIL Series chip resistors ranges from 0.003Ω to 1.0Ω, with a rated power of 3W at 70°C. Absolute TCRs are to ±100ppm/°C, ±250ppm/°C, and ±500ppm/°C, while available absolute tolerances range up to ±1%, ±2%, ±5% and ±10%. Operating temperature ranges from -55°C to +150°C.
Corpus Christi, TX
•High-Voltage Dual-Input Charger For More Reliable Battery Charging
FOR A variety of handheld equipment requiring both USB and AC/DC power adapter charging inputs, Diodes Incorporated has introduced the API9221 lithium ion/polymer battery charger IC. This dual-input IC enables USB host and DC adaptor connections, delivering charge currents in accordance with the USB standard or up to 1.2A, respectively. To ensure equipment can support a wide range of OEM and aftermarket chargers, the API9221 inputs can withstand a maximum voltage of 28V, which reduces external protection component requirements. To protect the IC, battery, and system, the charger will suspend charging when the input voltage exceeds 5.4V on the USB input or 6.9V on the DC adaptor input. The IC outputs also feature reverse current protection. The API9221 features a bypass LDO regulator, enabling a host controller to detect the connection of an out-of-specification supply voltage and safely keep the charger in its off-state condition until a valid supply is connected. The device offers excellent thermal regulation and protection, with the ability to reduce charge current to keep the die temperature within safe operating conditions. The IC follows the industry-standard CC/CV charging algorithm, and enables USB and adaptor charge currents and end-of-charge currents to be user-configured via external resistor settings. With only a 1% error across the device's operating temperature range, the IC ensures battery charging up to 4.2V. The battery charger IC is priced at $0.93 each in 1k quantities.
•Ultra-Miniature Pushbutton Switches in Vertical, Right Angle Configurations
C&K COMPONENTS has developed an ultra miniature pushbutton switch designated the FP Seriesthe RoHS compliant and compatible sealed switches are available in both vertical and right angle mount configurations, and feature an extended operating life to 50,000 cycles.”The FP Series switches measure just 5.6mm × 7mm, with a board height of only 5mm for the right angle version and 4.5mm × 7mm, with a board height of only 5.6mm for the vertical version,” said David Webber, director of product management for C&K Components. The switches feature gold over nickel-plated contacts and are available with or without a white, black or red cap. The switches feature a contact resistance of 10mA @ 2VDC, with an initial contact resistance of 80mohm maximum. Dielectric withstanding voltage is 500VDC between terminals/1 minute, while insulation resistance is 500Mohm minimum @ 500VDC. Typical bounce time is ~10ms. Maximum operating force is 6.9N and mechanical travel is 1.0mm. Operating temperature ranges from -20°C to +80°C. The switches are available in tray and bulk bag packaging.