by Petre Petrov @ electronicdesign.com:
The bipolar NE555 timer IC is widely used in inductorless dc-dc converters, most frequently in doubling and inverting converters. However, another very popular IC, the LM386 audio amplifier, may be a better solution in this application. Note that the results also depend on the specific manufacturer of these multisourced ICs and on the quality of the related components. (We will use only Schottky diodes, to reduce the voltage losses to the minimum.)
Comparing the NE555 Timer and LM386 Amplifier as Inductorless DC-DC Converters - [Link]
This application details how a dual-channel LDO may be used to provide a dynamic voltage scaling output. This function is useful when powering microcontrollers that have a wide operating voltage range: it is advantageous to lower the operating voltage of the MCU in order to achieve lower power consumption (when possible).
The MSP430G2001, for example, has a supply voltage range that varies depending on the system frequency and programming modes. As an example, when the system frequency is 1MHz and flash memory programming is not required, the supply voltage range spans from 1.8V to 3.6V. However, if flash memory programming is required, the supply voltage range contracts to 2.2V to 3.6V.
Dynamic Voltage Scaling with a Dual LDO - [Link]
by DAVID BURGOON @ edn.com:
There are several ways to produce a negative voltage from a positive voltage source, including using a transformer or two inductors and/or multiple switches. However, none are as easy as using the LTC3863, which is elegant in its simplicity, has superior efficiency at light loads and reduces parts count compared to alternative solutions.
The LTC3863 can produce a –0.4V to –150V negative output voltage from a positive input range of 3.5V to 60V. It uses a single-inductor topology with one active P-channel MOSFET switch and one diode. The high level of integration yields a simple, low parts-count solution.
AppNote: Inverting DC/DC controller converts a positive input to a negative output with a single inductor - [Link]
PMP9194 uses the TPS54020 synchronous-buck SWIFT converter with integrated FETs to provide a 10A/1V solution in less than 22mmx12mm of total board space area. This reference design uses a small 1.1uH inductor, 2x100uF ceramic output capacitors, and small 0402 external components to save space. The device switches at 300kHz and acheives 87% peak efficiency from a 12V input to a 1V output. The TPS54020 is ideal for powering low-voltage, high-current DSPs and FPGAs, and can be synchronized 180 degrees out-of-phase with another TPS54020 to reduce input ripple.
4.5V to 17V Input, 10-A Synchronous Buck Converter Optimized for Small Size and Low Output Voltage - [Link]
by sajjad Haidar @ edn.com:
A simple blocking oscillator circuit can be used to step up voltage using properties of coil inductance (V = L di/dt). Such a circuit is shown in Figure 1, which is more commonly called a Joule thief.
The output will be pulses of voltage that can be filtered using a diode and capacitor. As there is no regulation, the output voltage will vary with the input voltage or load. As this circuit uses a BJT, the supply voltage needs to be at least 0.7V to work, and with enhancement-mode MOSFETs, the supply voltage must usually be even higher.
MOSFET-based Joule Thief steps up voltage - [Link]
Spacewrench over at Dorkbotpdx published a new build, a Power Playground project:
It’s a PMOS/NMOS H-Bridge with FETs that can handle 3 amps or so, plus a SPI current sensor, some switches & a rotary encoder (not stuffed yet), and a 7-segment display, all controlled by a Teensy-3.1 running FreeRTOS.
I made this because I’m always running into battery, power, inductor and transformer issues I don’t have any experience with. The idea is to use the H-bridge configuration and current sensors to experiment with moderate-current PWM, motor control, power-line synchronization, battery charging and discharging, etc.
Power playground project - [Link]
App note(PDF) from NXP on DC-DC medium power small-signal MOSFETs.
This application note explores different methods of DC-to-DC conversion. It includes some examples of DC-to-DC down-converters using small-signal MOSFETs.
App note: Medium power small-signal MOSFETs in DC-to-DC conversion - [Link]
by Graham Prophet @ edn.com:
The MX100T from Aim-TTi (Aim Thurlby Thandar) is a 315W precision laboratory power supply’s three outputs can each provide 0 to 35 V at 0 to 3 A. Range switching extends the capabilities so that outputs can be set to 16 V/6 A or 70 V/1.5 A for maximum versatility; where higher power is needed from one output, internal switching circuitry enables up to 210 W arranged as either 35 V/6 A or 70 V/3 A.
All outputs are fully isolated and independent but voltage tracking can be selected to make two or even three outputs track a single voltage control. The isolated tracking capability is useful for creating tracking voltages to different ground points, tracking voltages of opposite polarity, or series and parallel connection of outputs.
Triple output lab power supply offers paralleling & tracking - [Link]
The board includes AMS1117 – 5V voltage regulator and AMS1117–3.3V, Voltage Regulator, providing fixed supply voltages. It features three voltage input options: a screw terminal connector, DC adapter connector and USB connector. It can operate on 6-12V DC power supply and has separate screw terminals for 3.3V and 5V outputs.
5V – 3.3V REG BOARD - [Link]
Who is the winner of umodule demoboard from Linear technology? In addition to getting to know the winner, you can also watch the video record from webinar…
Linear Technology’s family of DC/DC Module products simplifies your analog design. By integrating the DC/DC controller, power switches, magnetic, and a modest amount of capacitance, uModules power products will save precious space on the PCB and reduce the solution weight, development time, BOM qualification and procurement effort. You could find this out during webinar about Linear technology modules.From all of those who filled in our questionnaire after webinar we have drawn winner of the uModulu demoboard. The winner is František Bulko from EVPÚ a.s.
Congratulations to the winner.
Your way to simple and efficient power supply design with Linear Technology - [Link]