High-voltage Super Mox resistors meet the precision temperature stability requirements of high-accuracy and high-voltage systems
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High-voltage Super Mox resistors meet the precision temperature stability requirements of high-accuracy and high-voltage systems, combining a proprietary noninductive resistance system and designed to achieve low temperature coefficient, low voltage coefficients, high stability and increased high operating voltages.

With a resistance range from 1kohm to as high as 100Gohm on all models and tolerances of 0.05, 0.1, 0.25, 0.5, 1, 2, 5, 10%, the Super Mox low-TC precision high-voltage resistors are designed to meet the demanding requirements of high voltage power supplies, electron microscopes, X-ray systems, high resolution CRT displays and geophysical instruments.

Available with temperature coefficients of 5, 10, 15, 25, 50 and 100ppm/C, the resistors have a silicone conformal coating, gold plated leads and a standard operating temperature of -55 to +225C, although an extended temperature range to 350C is available.

High-voltage Super Mox resistors meet the precision temperature stability requirements of high-accuracy and high-voltage systems
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A new method of heatsinking solves the problem of overtorque when installing conventional TO-220 resistors and creates optimal thermal transfer between the resistor and the heatsink

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High-voltage Super Mox resistors meet the precision temperature stability requirements of high-accuracy and high-voltage systems, combining a proprietary noninductive resistance system and designed to achieve low temperature coefficient, low voltage coefficients, high stability and increased high operating voltages.

With a resistance range from 1kohm to as high as 100Gohm on all models and tolerances of 0.05, 0.1, 0.25, 0.5, 1, 2, 5, 10%, the Super Mox low-TC precision high-voltage resistors are designed to meet the demanding requirements of high voltage power supplies, electron microscopes, X-ray systems, high resolution CRT displays and geophysical instruments.

Available with temperature coefficients of 5, 10, 15, 25, 50 and 100ppm/C, the resistors have a silicone conformal coating, gold plated leads and a standard operating temperature of -55 to +225C, although an extended temperature range to 350C is available.

Rugged surface mount devices are specifically designed for surge/pulse applications and for circuits subject to extreme thermal cycling
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Power resistors handle hot duties
Providing design engineers with economical power resistors with high temperature capabilities, both power wirewound and film resistors are available for high volume applications

Providing design engineers with rugged surface mount devices specifically designed for surge/pulse applications and for circuits subject to extreme thermal cycling, TT Electronics IRC Wire and Film Technologies Division offers two versions of its popular cylindrical surface mount resistors. Designated the HSF Series and SMC Series, respectively, the cylindrical surface mount resistors approach wirewound performance levels in each area while providing OEMs with significant cost savings.

Both devices utilise IRC’s MetalGlaze thick film resistive elements on cylindrical ceramic substrates, which provide better heat dissipation, improved solderability and improved surge/pulse capabilities.

The two series are optimised for different applications.

The HSF Series features an unspiralled thick film element that offers three times the surge rating of IRC’s standard CHP Series, or as much as 10 times the rating of a conventional flat chip 2512 component.
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Designed to fit within the footprint of a standard 2512 chip, the HSF Series saves a significant amount of board space versus a comparable rated wirewound device.

The HSF Series resistors feature a power rating of 1W at 70C and a working voltage of 350V.

Resistance values of 5.9, 11, 27, 68 and 270ohm are offered, with a tolerance of +/-10%, and TCRs to +/-50ppm/C.

Maximum operating temperature is +150C.

IRC will also produce devices in custom resistance values to meet customer requirements.

The SMC Series resistors are designed to provide maximum thermal compliance for use in applications that are subject to extreme temperature cycling.

Metal caps fitted on the terminals of the cylindrical resistor body give the SMC Series devices exceptional thermal compliance, relieving stresses created from the TCE (thermal coefficient of expansion) mismatch between the ceramic component and the FR4 circuit board.

Designed to fit within industry standard 2512 and 3610 footprints, the SMC Series devices are ideal for automotive, power supply and industrial applications that require a surface mount resistor with superior surge and thermal characteristics.

The SMC Series resistors have a maximum power rating of 1W at 70C for the 2512 package and 2W at 70C for the 3610 size.

Resistance range is 1ohm to 2.0Mohm, with standard tolerance to +/-5%, and TCRs to +/-50ppm/C.

Maximum operating temperature is +150C.

IRC will also produce devices outside these specifications to meet customer requirements.

Typical pricing for the HSF and SMC Series resistors is approximately $0.18 each in quantities of 10,000.

Lead time is from stock to 4 to 6 weeks.

Welwyn Components has expanded its current sense resistor offering with the launch of the ULR series, its lowest ohmic value resistor, to minimise power consumption
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In response to demand for more energy efficient products, TT Electronics Welwyn Components has expanded its current sense resistor offering with the launch of the ULR series, its lowest ohmic value resistor, to minimise power consumption. The ULR series has been designed for current sensing in power electronic systems and the resistors are available in 1 to 3W power ratings, with a wide ohmic range starting from as low as 500uohm.

Products in the economical, low-inductance ULR series are surface mounted to maximise board space, making them well-suited to the industry trend for smaller products and are ideal for power supplies, DC/DC convertors and miniature electric motor control devices.

The series is RoHS compliant, has an ambient temperature range of -55 to +170C and the higher rated resistors feature a PCB clearance gap to maximise the thermal performance.

In addition, the series boasts a low temperature coefficient of 50ppm/C, essential for those involved in constructing devices and circuits for the detection of currents.
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Current sensing products are among the fastest growing resistive products in the industry today.

Direct resistive sensing remains the lowest cost method of generating a voltage proportional to current flow and submilliohm products to reduce the associated power loss.

John Graham, Marketing and Sales Director said: ‘Welwyn’s investment in the new ULR series comes in response to an increased demand for current sensing resistors as the world becomes more focused on energy efficiency’.

Power resistors are housed in a TO-220 style package and feature low thermal impedance and high insulation resistance for demanding applications
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Providing design engineers with high-power low-inductance devices in transistor-style packages, TT Electronics IRC Advanced Film Division has extended its MHP Series power resistors with 20 and 35W devices. Designated the MHP-20 and MHP-35, the highly stable power resistors are housed in a TO-220 style package and feature low thermal impedance and high insulation resistance for demanding applications.

According to Gary Bleasdell, Thick Film Business Unit Director for IRC’s Advanced Film Division, the MHP Series 20W and 35W resistors feature a package size that is much smaller than comparable wirewound devices of similar wattage ratings.

‘These resistors have an inherently lower inductance value than wirewound resistors, and because the MHP Series devices are designed for heatsink mounting, the equivalent wirewound resistors would need to be four to five times larger to achieve similar power ratings’, said Bleasdell.

‘The noninductive design, along with the high power levels and small package size, make the resistors ideal for applications involving high frequency and high speed pulse’.
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Additional applications for the MHP Series resistors include load resistors, motor control and drive circuits, switch mode power supplies, automotive electronics, industrial power equipment, UPS Systems and industrial computers.

The MHP-20 resistors feature inductance values of less than 50nH, and are available in power ratings of 10 and 20W, with a resistance range from 0.01ohm to 51kohm (10W ranges from 220ohm to 51kohm; 20W ranges from 0.01 to 220ohm).

Both the 10 and 20W resistors feature a thermal resistance of 5.9C/W, standard tolerances of +/-1 and +/-5%, and TCRs from 100 to 250ppm/C.

The MHP-35 resistors feature inductance values of less than 50nH and are available in power ratings of 20 and 35W, with a resistance range from 0.01ohm to 51kohm (20W ranges from 220ohm to 51kohm; 35W ranges from 0.01 to 220ohm).

Thermal resistance for the resistors is 3.3C/W, with standard tolerances of +/-1 and +/-5%, and TCRs from 100 to 250ppm/C.

IRC will also produce devices outside these specifications to meet customer requirements.

Both the MHP-20 and MHP-35 power resistors are RoHS-compliant.

Pricing for the MHP-20 and MHP-35 resistors is $1.80 each in quantities of 1000.

Lead time is from stock to 6 to 8 weeks.

Noninductive power resistor is rated up to 20W and housed in a small, thin TO-263 package suitable for high density PCB installation
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Power resistor keeps its cool
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Providing design engineers with a thermally efficient high current resistor in a surface mount package, TT Electronics BI Technologies SMT Division has developed a noninductive power resistor rated up to 20W. Designated the SMHP Series, the resistor is housed in a small, thin TO-263 package suitable for high density PCB installation.

According to Jim Rieley, Sales Director for BI Technologies’ SMT Division, the TO-263 style package offers extremely low thermal resistance.

‘The SMHP Series resistors are thermally enhanced and the design of the package allows them to be directly mounted to a heatsink’, Rieley said.

‘Because the design provides complete thermal flow throughout the device, the resistors are being specified for applications in automotive electronics, switch-mode power supplies, and high frequency snubber and pulse handling circuits’.
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The surface mount power resistors are also ideal for high precision CRT colour video amplifiers, pulse generator load resistors, inrush current protection, and bleeder resistors.

The SMHP Series device is an extension of the company’s MHP Series through-hole resistors.

The MHP Series noninductive high power resistors are available in five power ratings (20 to 140W) and three TO-style package types, including TO-126, TO-220 and TO-247.

The SMHP Series resistors are rated for 20W power dissipation, with resistance ranges from 0.01 to 220ohm with values to 51kohm available.

TCRs range from 50 to 250ppm/C, with tolerances of +/-5 and +/-1%.

Maximum operating voltage is 500V and dielectric withstanding voltage is 2000V DC.

Thermal resistance is 3.3C/W from the resistor’s ‘hot spot’ to the package’s metal flange and operating temperature range is -55 to +155C.

BI Technologies will also produce devices outside these specifications to meet customer requirements, with comprehensive application engineering and design support available for customers worldwide.

Typical pricing for the SMHP Series resistors is US $1.00 to $1.60, depending on resistance value.

Samples are available immediately for engineering evaluation and customer prototypes.

The KW006-010TM Series of sixteenth brick isolated power modules embodies a new generation of single output DC/DC power convertors
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Available now from Tyco Electronics Power Systems, the KW006-010TM Series of sixteenth brick isolated power modules embodies a new generation of single output DC/DC power convertors. Designed for optimum efficiency and power density, this 33W DC/DC convertor series joins the 50W KW010/015/020/025 products as an ideal choice for small space, high current and low voltage applications in enterprise equipment, data processing equipment, access, wireless and optical network equipment, and distributed and hybrid power architectures.

Delivering up to 33W of output power, KW Series convertors provide output voltages of 3.3V at 10A and 5V at 6A with an input voltage range of 36 to 75V DC.

The series incorporates synchronous rectification technology and innovative packaging techniques to achieve high efficiency reaching 87% at 3.3V full load.

KW Series convertors operate over the industrial temperature range of -40 to +85C.
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The modules have an industry standard sixteenth brick footprint of 33.0 x 22.9 x 8.50mm and are RoHS compliant (2002/95/EC).

The KW Series modules are available in surface mount (SMT) - tape and reel packages.

Standard features include remote on/off, negative logic, output voltage adjustment, remote sense, overvoltage (latching), overcurrent and over-temperature protection (nonlatching).

Remote on/off positive logic is available as an option.

‘We are thrilled that the KW Series isolated convertors are now available’.

‘It combines industry and customer requirements into a standard, industry-accepted footprint’, said Sabi Varma, Vice President of Marketing and Business Operations at Tyco Electronics Power Systems: ‘The KW convertors’ high power density, high efficiency and compact design make the series an ideal choice for our end users’.

The KW Series modules are priced at US $24.80 in 1000 unit quantities.

Emerson Network Power has announced the availability of the industry’s smallest front-end power solution to date for use on latest-generation telecomms cards
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The majority of existing Advanced Telecom Computing Architecture (ATCA) bus convertors employ a combination of front-end interface and conversion module, consuming valuable board space. The new Artesyn dual-input ATC210 bus convertor is a fully integrated solution that occupies 20-40% less space than competing solutions.

It combines an exceptionally small footprint, high power density isolated DC/DC convertor with advanced digitally programmable power management functions.

The convertor has a 5.9 x 4.6cm footprint and a typical full load efficiency of 89%, yielding a power density in excess of 4W/cm3.

The ATC210 is expressly designed for use in ATCA systems, and is an ideal design choice for many other space-constrained systems that employ distributed power architectures.

According to Mark Rice, Vice President of DC/DC Marketing for Emerson Network Power: ‘Many major telecomms companies have come to regard ATCA as the best means of meeting future systems requirements’.

‘It is an open standard architecture, which provides an ideal path away from expensive proprietary platforms’.
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‘From a power perspective, the market could become significant - and each ATCA system can contain up to 14 blades, each of which will require at least one bus convertor’.

The ATC210 bus convertor is rated at 210W.

It has dual inputs, each capable of accommodating a very wide input voltage range of -36 to +72V, and generates two independent, isolated DC outputs.

The main 12V output can deliver up to 17.5A and is intended for powering an on-card intermediate bus.

The secondary output is for supplying peripheral power management circuitry; it is rated at 1.8A, and is resistor programmable over the range 3.13 to 3.47V.

The convertor is equipped with I2C serial bus and direct high-speed interfaces for monitoring, reporting and digital programming of fault thresholds.

Built-in power management functions include input ORing, inrush control and transient protection.

Artesyn ATC210 bus convertors are designed specifically for high availability telecomms applications.

Based on a thermally efficient open-frame design, they have an ambient operating temperature range of -25 to +85C and employ conservative derating criteria to achieve a typical MTBF in excess of 2 million hours (in accordance with Telcordia SR-332).

The convertors are comprehensively protected against overload and fault conditions, and have a two-year warranty.

They meet the rigorous ETS 300 386-1 immunity and emission standards, feature EN60950-1 (TUV Product Service) and UL/cUL60950-1 safety approvals, and are Pb-free (RoHS 6/6 compliant) products.

Sample ATC210 bus convertors are available now.

Pricing in 1000-piece quantities is US $148, and the standard lead-time is stock to 8 weeks.

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HiTek Power is introducing the HG70, a 72W X-ray generator power supply module, at Electronica 2006. This supply for grounded-cathode tubes incorporates the high voltage and filament power supply stages and all necessary beam control circuitry. Measuring only 204 x 73 x 127mm, the new unit is the smallest in the market for its power capabilities.

It is available with an optional interface to enable full control via RS232.

The HG70 is supplied from a 24V DC rail and provides up to 60kV for the X-ray tube anode with a maximum current of 1.2mA.

It also provides a low voltage output for the X-ray tube filament, with a current of up to 3.5A and a maximum voltage of 5.5V.
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High levels of remote control and monitoring meet the needs of modern X-ray systems to be controlled more finely and the growing need to protect ever-more-expensive tubes.

The new unit has been designed to offer the high stability and low ripple demanded by today’s applications.

Ripple on the high voltage output is less than 0.05% +10V peak-to-peak.

Load regulation for voltage is less than 0.01 per cent +/-1V from no load to full load, while for beam current it is less than +/-2uA.

Stability is +/-0.1% over an 8 hour period after 30 minutes warm-up.

Control and monitoring is via a 15-way D-type connector, front-panel potentiometers and an optional RS232C interface.

It includes control of on/off, high voltage output, maximum and standby filament currents; and monitoring of high voltage output, and beam and filament currents.

High-voltage high-power DC/DC point-of-load regulators provide new features and various output power capabilities
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A new family of high voltage, high power DC/DC uModule point-of-load (POL) regulators from Linear Technology provides new features and various output power capabilities. The LTM4601, LTM4602 and LTM4603 each contain all the components required to build a 6 to 48A point-of-load (POL) regulator, including the inductor, power MOSFETs, DC/DC controller, compensation circuitry and input/output bypass capacitors.

The devices’ compact 15 x 15 x 2.8mm LGA package protects the solution from the external environment and the modules’ thermal enhancements provide highly efficient heat removal.

The uModule packages provide the size, form-factor and simplicity of a surface-mount IC.

Designing with this family of uModule POL regulators requires no knowledge in switch-mode power supplies, greatly simplifying the task for a digital circuit designer.

Circuit simulation models and layouts are available for each device.

The uModules serve a broad range of applications, including industrial automation, RAID and high availability systems, blade servers, medical imaging, wireless basestations, computing, and networking systems.
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Each DC/DC uModule is rated for operation from 4.5 to 28V (20V for the standard voltage version).

The output voltage is adjustable with one resistor from 0.6 to 5V.

The new features added to the new family include phase-lock loop (PLL) synchronisation for lower switching noise as well as for PolyPhase operation for paralleling multiple uModule regulators to deliver higher output current, true differential remote sensing for precision regulation of low voltage, high current loads such as FPGAs, DSPs and ASICs, and tracking/margining for proper startup of multiple voltage rail systems.

The LTM4601, LTM4602, LTM4603 and the previously announced LTM4600 uModule feature a current-mode architecture and provide fast short-circuit protection as well as over- and undervoltage protection.

Because of their small size and light weight (1.73g) they can be handled by any pick-and-place machine.

In addition, their low profile design is effective in enabling unobstructed air flow especially in very dense systems.

‘The addition of these five new power uModules further enables quick and easy design of a range of power supplies’, stated Don Paulus, General Manager of the Power Business Group.

‘Their light weight and low profile packaging allow the uModules to be soldered onto the back side of many circuit boards, making efficient use of board space, and leaving topside space for sophisticated digital ICs such as FPGAs and DDR memory’.

‘We anticipate a high level of interest in a broad range of applications’.

The LTM4601 is a full-featured 12A output uModule DC/DC solution.

It includes PLL, tracking and margining, and remote sensing.

The LTM4603 is rated for 6A and has the same features, footprint and layout as the LTM4601.

Each device is offered in two voltage options: 4.5-20 or 4.5-28V.

They are rated for operation from -40 to +85C.

The LTM4601-1 and LTM4603-1 are identical to the LTM4601 and LTM4603, respectively, except the remote sense function is removed.

They allow current sharing by paralleling the outputs of multiple devices for higher load current.

Each device is offered in two voltage options of 4.5-20 or 4.5-28V.

They are rated for operation from -40 to +85C.

The LTM4600 is a 10A uModule DC/DC intended for POL solutions compatible with the reduced feature set.

The LTM4602 is rated for 6A and has the same features, footprint and layout as the LTM4600.

Each device is offered in two voltage options of 4.5-20 or 4.5-28V.

They are rated for operation from -40 to +85C.