Tag Archives: Switching

TPS61092 Boost Converter on Test Bench

luckyresistor.me tests his TPS61092 boost converter with a thermal camera and shares the results.

For my current project I searched for a good boost power converter which is able to deliver continuous 400mA power for various sensors.

There are an endless number of good boost converters around, but not many can be hand soldered to a board. I would really like to see some like the TPS61092 with SOIC or similar packages. The biggest problem seems to be the heat transport, why most chips have to be mounted flat on the board.

TPS61092 Boost Converter on Test Bench – [Link]

LT8364 DC/DC converter can be configured multiple ways

Analog Devices has announced the LT8364 current mode, 2MHz step-up DC/DC converter. It has an internal 4.0A, 60V switch and operates from an input voltage range of 2.8 to 60V.

The ‘Power by Linear’ LT8364 is suitable for applications with input sources ranging from a single-cell Li-Ion battery to multi-cell battery stacks, automotive inputs, telecomms power supplies and industrial power rails.

The LT8364 can be configured as either a boost, SEPIC or an inverting converter. Its switching frequency can be programmed between 300kHz and 2MHz, enabling designers to minimise external component sizes and avoid critical frequency bands, such as AM radio, says Analog Devices. It offers over 90 per cent efficiency while switching at 2MHz. Burst Mode operation reduces quiescent current to only nine microA while keeping output ripple below 15mVp-p. There is the option of a small 4.0 x 3.0mm DFN, or high voltage MSOP-16E package, with small external components to ensure a compact footprint while minimising cost, adds Analog Devices.

The LT8364’s 100-mOhm power switch delivers efficiencies of over 95 per cent. It also offers spread spectrum frequency modulation to minimise EMI concerns. A single feedback pin sets the output voltage whether the output is positive or negative, minimising pin count. Other features include external synchronisation, programmable under-voltage lockout (UVLO), frequency foldback and programmable soft-start.

The two versions available are the LT8364EDE in a 4.0 x 3.0mm DFN-12 package and the LT8364EMSE which is offered in a high voltage MSOP-16E (with four pins removed for high voltage spacing). Industrial temperature (operating at -40 to +125 degree C), the LT8364IDE and LT8364IMSE, and high temperature models, the LT8364HDE and LT8364HMSE, with temperature ranges of -40 to +150 degree C, are also available. All versions are available from stock.

The design includes a bias pin for higher efficiency and positive or negative output voltage programming is possible with a single feedback pin. The device has optional spread spectrum frequency modulation to minimise EMI.

Helix Semiconductors starts production of DC-DC power chip

Fabless power semiconductor startup Helix Semiconductors has started mass production of its MxC200, a configurable high-efficiency 15W DC-DC power chip.

Previously known as the HS200, the MxC200 takes voltage input ranging from 12V to 48V and converts it to selectable lower voltages. For example, when configured as a 48V input to 12V output, the device offers greater than 97 percent peak efficiency and greater than 90 percent efficiency at full load. by Nick Flaherty @ eenewseurope.com

With the MxC200 and other MuxCapacitor-based products, Helix Semiconductors is answering the demand for more energy-efficient power ICs in the burgeoning AC-DC and DC-DC markets,” said Harold Blomquist, president and CEO of Helix Semiconductors. “The MxC200 features a unique three-stage process, each of which divides its input in half. Power can be pulled from any of its three outputs simultaneously up to 15W. The company’s MuxCapacitor technology enables the MxC200 to achieve unprecedented high efficiency and to stay nearly flat from full load down to 5 percent load.

Helix Semiconductors starts production of DC-DC power chip – [Link]

Synchronous four-switch buck-boost controller suits transport and medical use

Synchronous four-switch buck-boost controller suits transport and medical use

A 150V high efficiency four-switch synchronous buck-boost DC/DC controller, the LTC3777, by Analog Devices operates from input voltages above, below or equal to the regulated output voltage and had an efficiency of up to 99 per cent.

The Power by Linear DC/DC controller has an input voltage of 4.5 to 150V and operates from a high input voltage source or from an input that has high voltage surges, eliminating the need for external surge suppression devices. This, says Analog Devices, makes it suitable for transportation, industrial and medical

To prevent high on-chip power dissipation in high input voltage applications, the LTC3777 integrates a low quiescent current high efficiency switching bias supply for its internal power consumption. The output voltage of the LTC3777 can be set from 1.2 to 150V at output currents up to tens of amps, depending on the choice of external components. Output power up to 500W can be delivered with a single device. Higher powers can be achieved when multiple circuits are configured in parallel. The LTC3777’s 1.5-Ohm n-channel MOSFET gate drivers can be adjusted from 6.0 to 10V, enabling the use of logic-level or standard-threshold MOSFETs.

The LTC3777 employs a proprietary current mode control architecture for constant frequency in buck, boost or buck-boost modes. The operating frequency can be synchronised to an external clock from 50 to 600kHz, while an I/O constant current loop provides support for battery charging and over-load protection. The user can select either forced continuous mode or discontinuous mode to maximize light load efficiency. There are also seamless transfers between operating regions, a power good output voltage monitor, adjustable soft-start and input overvoltage lockout, and output voltage disconnect during shutdown.

The LTC3777 is available in a 48-lead 7.0 x7.0mm e-LQFP package with pin skipping for high voltage spacing. Extended and industrial versions are available from –40 to +125 degree C.

Synchronous four-switch buck-boost controller suits transport and medical use – [Link]

150VIN & VOUT Synchronous 4-Switch Buck-Boost Controller with Integrated Switching Bias Supply

Analog Devices announces the Power by Linear™ LTC3777, a 150V high efficiency (up to 99%) 4-switch synchronous buck-boost DC/DC controller, which operates from input voltages above, below or equal to the regulated output voltage. Its 4.5V to 150V input voltage range operates from a high input voltage source or from an input that has high voltage surges, eliminating the need for external surge suppression devices, ideal for transportation, industrial and medical applications.

To prevent high on-chip power dissipation in high input voltage applications, the LTC3777 integrates a low quiescent current high efficiency switching bias supply for its internal power consumption. The output voltage of the LTC3777 can be set from 1.2V to 150V at output currents up to tens of amps, depending on the choice of external components. Output power up to 500W can be delivered with a single device. Higher powers can be achieved when multiple circuits are configured in parallel. The LTC3777’s powerful 1.5Ω N-channel MOSFET gate drivers can be adjusted from 6V to 10V, enabling the use of logic-level or standard-threshold MOSFETs.

The LTC3777 employs a proprietary current mode control architecture for constant frequency in buck, boost or buck-boost modes. The operating frequency can be synchronized to an external clock from 50kHz to 600kHz, while an input/output constant current loop provides support for battery charging and overload protection. The user can select either forced continuous mode or discontinuous mode to maximize light load efficiency. Additional features include seamless transfers between operating regions, a power good output voltage monitor, adjustable soft-start and input overvoltage lockout, and output voltage disconnect during shutdown.

The LTC3777 is available in a 48-lead e-LQFP package with pin skipping for high voltage spacing. Extended and industrial versions are available from –40 to 125°C.

Summary of Features: LTC3777

  • 4-Switch Synchronous Current Mode Buck-Boost Architecture
  • Operation with Input Voltages Above, Below or Equal to the Output Voltage
  • 4.5V to 150V Input Voltage Range
  • 1.2V to 150V Output Voltage Range
  • Up to 99% Efficiency
  • Integrated Switching Bias Supply
  • Input or Output Average Current Limit
  • Adjustable 6V to 10V MOSFET Gate Drivers
  • Compatible with Logic-Level or Standard-Threshold NMOS
  • 500 Watts Output Power Capable with a Single Device
  • Fixed Synchronizable Operating Frequency from 50kHz to 600kHz
  • Output Voltage Disconnect from VIN During Shutdown
  • Adjustable Soft-Start
  • ±1% Reference Voltage Accuracy over -40°C to 125°C
  • 48-Lead e-LQFP Package with High Voltage Pin Skipping

[source]

The behavior of electro-magnetic radiation of power inductors in power management

Application note form Würth Elektronik about EM radiation radiated from inductors in DC-DC converters.

This Application Note focuses on the Electro-Magnetic (EM) radiation behavior of power inductor(s) in DC-DC converters, which is dependent on several parameters such as ripple current, switching frequency, rise & fall time of a switching device, the core material and its permeability and suggests several design tips to mitigate these EMI effects.

The behavior of electro-magnetic radiation of power inductors in power management – [Link]

60V input 5V @3A output DC-DC Converter for Industrial and Automotive

This is a 60 V 3A step down DC-DC converter. Sample applications are: 12 V, 24 V and 48 V Industrial, Automotive and Communications Power Systems. The TPS54360 is a 60 V, 3 A, step down regulator with an integrated high side MOSFET. The device survives load dump pulses up to 65V per ISO 7637. Current mode control provides simple external compensation and flexible component selection. A low ripple pulse skip mode reduces the no load supply current to 146 μA. Shutdown supply current is reduced to 2 μA when the enable pin is pulled low. Under voltage lockout is internally set at 4.3 V but can be increased using the enable pin. The output voltage start up ramp is internally controlled to provide a controlled start up and eliminate overshoot. A wide switching frequency range allows either efficiency or external component size to be optimized. Frequency fold back and thermal shutdown protects internal and external components during an overload condition.

60V input 5V @3A output DC-DC Converter for Industrial and Automotive – [Link]

USB To 12V Boost Converter

This project provides 12V output from any USB power source, like PC USB port, USB adapter or power banks. LM2577ADJ boost converter IC is the heart of the project. The IC can handle load up to 800mA, it’s advisable to use only 200mA load on output to be on the safe side. The LM2577 are monolithic integrated circuits that provide all of the power and control functions for step-up (boost), fly back, and forward converter switching regulators. The device is available in three different output voltage versions: 12V, 15V, and adjustable. Requiring a minimum number of external components, these regulators are cost effective, and simple to use. Listed in this data sheet are a family of standard inductors and fly back transformers designed to work with these switching regulators. Included on the chip is a 3.0A NPN switch and its associated protection circuitry, consisting of current and thermal limiting, and under voltage lockout. Other features include a 52 kHz fixed-frequency oscillator that requires no external components, a soft start mode to reduce in-rush current during start-up, and current mode control for improved rejection of input voltage and output load transients.

USB To 12V Boost Converter – [Link]

Torpedo 2 – a cheap & powerful 3A DC/DC converter with built-in charger

Boris Landoni @ open-electronics.org presents their second version of Torpedo, a kind of DC-DC converter able to provide 5V output from a variety of sources. He writes:

Some time ago we had introduced you to the Torpedo switching power supply, a particular kind of DC/DC power supply called SEPIC capable of supplying 5 V from several external supply sources, such as an external voltage between around 3.5 and 20 V, the 5 V coming from a USB connector or the 3 to 7 V supplied by a LiPo battery. The very small power supply also had a circuit capable of charging the battery up through external sources, where available.

Specifications

  • triple power source: USB, LiPo battery and an external source;
  • a wide range of input voltage values: 6,5 – 18 V;
  • can supply a maximum current of 3 A;
  • high efficiency, even over 85-90%;
  • built-in charger for LiPo single cells;
  • can switch from battery-powered to another source without interruption;
  • 5 V output with high stability when load varies and low ripple;
  • possibility to turn off the only output leaving the step-down converter and the charger active;
  • possibility to automatically deactivate the output if power supply comes from the USB connector which is limited to 500 mA current by the specs; if there is a battery, power supply is granted by that;
  • status LEDs indicating charge, the power supply used, output activation and so on.

Torpedo 2 – a cheap & powerful 3A DC/DC converter with built-in charger – [Link]

24-48V to 5V – 3A DC-DC Converter

24-48V input voltage range 3A output current DC-DC Converter using BD9G341AEFJ IC from ROHM semiconductor. This IC is ideal for high voltage to low voltage converter with 3A output current. Pin configuration of the board with 3 Pin horizontal mounting of the regulator is similar to LM7805 LDO regulator and is suitable to use this IC as replacement which can provide more current and take high voltage input.

Different voltage output are possible by changing few components. Refer to datasheet for the same. Example circuit can provide 5.1V/3A with input supply range 24-48V DC and operating frequency 200 KHz.

24-48V to 5V – 3A DC-DC Converter – Link