This reference design from TI demonstrates the LM46002 SIMPLE SWITCHER® Synchronous Buck Converter and the LMZ21701 SIMPLE SWITCHER® Nano Module. The LM46002 provides a regulated 12V rail from an input of 15V to 60V. The 12V rail is then regulated down to 5V, 3.3V, and 1.8V rails using three LMZ21701 nano modules. Each rail can provide up to 1A of load current. This modules’ wide input voltage capability and small solution size, ease of use, high efficiency and modular design was seen at APEC.
15V to 60V Wide Input Four-Output SIMPLE SWITCHER – [Link]
TI’s PMP9476 is a non-synchronous buck converter plus a non-sync boost controller accepting an input voltage of 3.5V to 40V, with 5V output at up to 3A of current to the load. It features a small form factor; with PFET to replace LM3481 controller rectifier to improve efficiency and low component temperature rise; and reverse polarity protection built in. The nominal switching frequency of the design is 300kHz. The board is a 4- layer PCB with 1oz copper on all 4 layers. The design incorporates an LM3481 boost controller acts as a pre-boost stage for the LM26003 buck when start-stop occurs.
15W Automotive Start Stop Power Supply – [Link]
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]