Ericsson added three DC/DC converters to its PKJ 4000 Series for RFPA (radio frequency power amplifier) applications. The PKJ 4316 API is rated at 350W, 48Vin/28.2V/12.4A. It is joined by the PKJ 4316 P rated at 48Vin/28.2V/11A 310Wout, and the PKJ 4216N PI that is rated at 48Vin/30.2V/8.3A 250Wout. Available in the industry standard half-brick format, these high-power units operate over an input voltage range of 35V to 75V DC. The units are RoHS-compliant and are based on a mechanical design using metal to metal to attach the base plate, giving high thermal conductivity, good electrical isolation and desirable mechanical strength. The converters feature the standard RFPA height of 12.7mm.
The fully featured converters include output over-voltage, input under-voltage, over-temperature and output short-circuit protection, together with soft-start, remote sensing, remote control and output voltage adjust functions.
Keeping radiated EMI to a minimum, the converters include a ground plane in the PCB area under the DC/DC converter. This approach returns switching noise to ground as directly as possible, with improvements to emissions and susceptibility.
Emerson Network Power launched two intermediate bus converters (IBCs) that are said to be capable of providing exceptionally high levels of usable output power with a conversion efficiency of 97 percent. Forming the latest additions to the Artesyn family of high power density IBCs, the products comprise a 300W eighth-brick and a 642W quarter-brick.
Both IBCs are intended primarily for powering multiple downstream non-isolated PoL (point-of-load) converters in distributed power systems with 9.6V intermediate bus architectures, and applications with well regulated 48V input voltages, or for feeding general-purpose wide input PoL converters which can tolerate some supply variation.
The IBC60 quarter-brick and IBC32 eighth-brick IBCs are designed to operate from a 38V to 55V DC supply, have a fixed 5:1 conversion ratio and generate an isolated, unregulated DC output. When fed with a 48V DC supply, the converters generate a 9.6V DC output. The IBC60 can provide up to 60A – achieving a power density in excess of 400W/in3 – and a typical load regulation figure of 2.5 percent for all load conditions; the IBC32 has a 32A output capability and a typical load regulation figure of 2.3 percent.
<B>Companies Mentioned in Product Technology Review</B>
• Ericsson
www.ericsson.com
• Emerson Network Power
www.artesyn.com
• ON Semiconductor
www.onsemi.com
• Texas Instruments
www.ti.com
• Advanced Analogic Tech
www.analogictech.com
• Maxim Integrated Products
www.maxim-ic.com
<B>Ericsson</B>
Product: PKJ 4000 PI Series
Key Highlights:
• Industry standard half-brick
57.9mm x 61mm x 12.7mm
• High efficiency typ. 91.5 percent at
30.2 Vout half-load.
• 1,500V DC input to output
isolation
• 3 million hours predicted MTBF
Emerson Network Power
Product: IBC 60A 600W intermediate bus converters
Key Highlights:
• 48V input with isolated 9.6V output
• High efficiency of 97 percent
• Desirable usable output power levels
• High power density open-frame technology
• Wide operating ambient temperature range
<B>ON Semiconductor</B>
The NCP1523 step-down PWM DC/DC converter for portable applications powered from 1-cell Li-ion or 3-cell Alkaline/NiCd/NiMH batteries is available in an adjustable output voltage from 0.9V to 3.3V. It uses synchronous rectification to increase efficiency and reduce external part count. The device also has a built-in 3MHz (nominal) oscillator which allows use of a small inductor and capacitors.
Model: NCP1523
Type: Step-down PWM DC/DC Converter
Size: 2.1mm x 1.1mm
Input: 2.7V to 5.2V
Output: 0.9V to 3.3V (adjustable)
Operation/Clock: 3MHz high switching frequency
Efficiency: Up to 93%
Regulation:
• Reference line: 0.1% typ.
• Output line: (VOUT) 0.1%
• Voltage load: 0.001%/mA
Features:
• Sources up to 600mA
• Synchronous rectification for higher efficiency
• Thermal limit protection
• Shutdown current consumption: 0.3μA
Price: $0.75 ea. in 1,000-unit quantities
<B>Texas Instruments</B>
The TPS6505x integrated power management ICs are for applications powered by one Li-ion or Li-Polymer cell, which require multiple power rails. The IC provides two efficient, 2.25MHz step-down converters targeted at providing the core voltage and I/O voltage in a processor based system. The step-down converters enter a low power mode at light load for efficiency across a wide range of load currents.
Model: TPS65050
Type: Six-channel Power Management IC with Two DC/DC Converters
Size: 4mm x 4mm
Input: 2.5V to 6V (for DC/DC converters)
Output: Voltages: externally adjustable;
Current: 2 x 0.6A
Operation/Clock: 2.25MHz fixed frequency
Efficiency: Up to 95%
Regulation:
Integrated: two 400mA LDOs and two 200mA LDO regulators
Features:
• Output Voltage accuracy in PWM mode: ±1%
• 180° out-of-phase operation
• Power save mode at light load current
• Total 32μA (typ.) quiescent current for both DC/DC converters
Price: $2.75 ea. in 1,000-unit quantities
<B>Advanced Analogic Tech.</B>
The AAT1210 high-power DC/DC boost (step-up) converter has an input voltage range from 2.7V to 5.5V. The output voltage can be set from VIN +0.5V to 18V. It is suited for battery powered and consumer applications. The IC operates at frequencies up to 2MHz, enabling small external filtering components. Hysteretic current mode control provides desirable transient response with no external compensation.
Model: AAT1210
Type: DC/DC Boost Converter
Size: 3mm x 4mm
Input: 2.7V to 5.5V
Output: Max continuous output: 900mA at 5V, 300mA at 12V, 150mA at 18V
Operation/Clock: Up to 2MHz switching
Efficiency: Up to 90%
Regulation:
• VLOADREG: IOUT = 0 to IOUT (max.) mA: 0.01% mA
• VLINEREG/VIN: VIN = 3.0V to multiplied by the load current to 5.5V: 0.6%/V
Features:
• 1mm height inductor, small ceramic capacitors
• True load disconnect feature guarantees <1μA
• Optional dynamic voltage management
• Hysteretic current mode control
Price: $1.31 ea. in 1,000-unit quantities
<B>Maxim</B>
Maxim Integrated Products’ MAX8640Y/8640Z step-down converters use a proprietary PWM control scheme that optimizes the switching frequency for high efficiency with small external components and maintains low output ripple voltage at all loads. The 8640Z switches at up to 4MHz to allow a small 1uH inductor and 2.2uF output capacitor. The 8640Y switches at up to 2MHz.
Model: MAX8640Y/8640Z
Type: Synchronous Step-down DC/DC Converters
Size: 2mm x 2.1mm; 1.5mm x 1mm
Input: 2.7V to 4.9V
Output:
• Presets from 0.8V to 2.5V;
• 500mA current guaranteed
Operation/Clock:
Up to 2MHz (8640Y)
Up to 4MHz (8640Z)
Efficiency: See online datasheet
Regulation:
• DC feedback from LX node; RL= inductor DC resistance, multiplied by the load current
• Ultra fast line- and load response
Features:
• 1μH/2.2μF or 2.2μH/4.7μF external components
• 24μA quiescent current
• Low output ripple at all loads
• Ultrasonic skip mode down to 1mA loads
• Fast soft-start eliminates inrush currents
Price: $1.58 ea. in 1,000-unit quantities
<I>*Please contact the manufacturer(s) for the complete specs/characteristics and the conditions pertaining to the specs/characteristics shown above.</I>
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