I explain buck converters (a type of switch mode power supply) and how to build a 5V 5A power supply using an LM2678.
How to build a switch mode power supply! DC-DC buck converter tutorial! - [Link]
Bertho posted a digitally controlled PSU design in the forum. He writes:
The design is for 0…30V and 0…3A (90W) controllable at ~1mV and ~0.1mA steps. The actual accuracy is still out for testing and I assume that noise and non-linearity will be a factor to look at when time comes. The basic design allows for 0…42V (max 45V) and (at least) 0…4A, but then all the components should be re-calculated to match such setup. Also, some components need to be voltage matched for a higher input voltage.
The design is a dual control-loop where the first stage is a switching PSU which is fed back to assure a 2.5V drop over the secondary analog control stage. The secondary stage is also responsible for the current limiter. The idea here is to reduce the power loss in the BJT (Q4) in the analog stage.
Digitally controlled bench PSU - [Link]
This project is a solution to power up most of devices or projects requiring dual (+/-12V) power supply.
Symmetric +/-12 VDC power supply has been designed for audio applications, can power up microphone pre-amplifier, audio buffers, audio mixer, distributions amplifier, headphone amplifier, VU meter and few o other equipment or projects required dual supply.
+/-12V Dual Power Supply - [Link]
Programmable DC, AC, current- and high-voltage power supplies, electronic loads, UPS, inverters and chargers of small and high power suitable for production and servicing – this is Elektro Automatik.
When we establish a production or testing workplace, we usually can´t omit a suitable power supply. Sometimes a „universal“ like 2x30V/3A is sufficient, but often not. It´s well known fact for those of you, who produce devices various devices requiring higher current or higher voltage. Typical representatives are equipment for automotive industry, various drives, backup sources, solar devices etc. In these case tens to hundreds Amps and/or hundreds to thousands of Volts are no rarity.
Right for these purposes, German company Elektro Automatik produces devices and systems for power supply and simulation of conditions in a real operation. Adjustable DC and AC power supplies, current sources, electronic loads and other devices can serve for a thorough examination of your devices even in “border conditions” and they can help to discover eventual hidden faults which might occur later in a real operation. Many Elektro Automatik products are programmable and they´re also connectable to some of common buses like CANopen, Profibus, ProfiNet, DeviceNet, Modbus, Ethernet and also RS232. Also interesting are for example electronic loads with energy recovery, where the lost energy doesn´t transform to heat but returns back to mains line with efficiency of about 93%.
Upon request, we´re able to provide you with any product from the Electro Automatik catalogue (14,5 MB).
Where common power supplies end, there the Elektro Automatik begins - [Link]
An SMPS application using PIC16F785 from Microchip. [via]
In this application note, we will examine a typical buck topology intelligent SMPS design using the PIC16F785.
The design presented here shows an alternative single-chip approach to adding intelligence to SMPS designs. The basic design is really unchanged. There are current and voltage feedback loops, a counter-based PWM is used to generate the reference voltage to the voltage loop, and the microcontroller uses the reference voltage to modify the operation of the system in response to conditions sensed through the ADC.
App note: Switching power supply design with the PIC16F785 - [Link]
This project is a solution to power up most of devices or projects requiring dual (+/-) adjustable power supply. The circuit is based on LM317 positive and LM337 negative voltage regulators. LM317 series of adjustable 3 terminal regulator is capable of supplying in excess of 1.5A over a 1.2V to 30V DC output range, due to TO3 package of IC and large heat sink the power supply can handle maximum load current.
Dual Adjustable Power Supply - [Link]
Prototyping is a useful and powerful method in electronics which lets us analyze a circuit before using it in a system or turning it into a product. In this process we may need a single supply or multiple supplies to power the circuit depending on the type of the application. For example, an op-amp circuit may need a symmetrical supply such as +12V and -12V or a logic circuit may require both 5V and 3.3V at the same time. Some applications may need three or more. This means we should have a bench supply with multiple outputs or multiple bench supplies in the environment. This may not be always possible. This DIY Prototyping Board is designed to provide all the most used supply voltages that a designer will need during prototyping a circuit. The switching power supplies on the board output 3.3V, 5V, 12V and -12V rated at 1A independently. In addition those there are two precise voltage references at 5V and 2.5V provided especially for op-amp based applications.
DIY Prototyping Board with 3.3V, 5V, 12V and -12V Built in Power Supplies - [Link]
This project is a 8-12Vdc to +48Vdc DC-DC converter based on MC34063 switching regulator. It’s a simple project of a DC-DC converter to make a phantom power supply for professional microphones. It can deliver 15-20mA at 48VDC. It ‘s based on MC34063 DC-DC step-up, step-down and boost converter. Input is between 8-12V DC and the output +48VDC/10-20mA.
9V to 48V DC-DC Converter - [Link]
This project is based on the 0-30 VDC Stabilized Power Supply with Current Control 0.002-3 A and a new PCB layout is introduced here. It’s a stabilized power supply with variable output voltage in the range 0-30Vdc (33Vdc peak) – and variable current 3A and is ideal for your laboratory power supply.
0-30V Laboratory Power Supply - [Link]
Hobby grade R/C cars with high voltage batteries require some form of voltage regulation. The batteries in those vehicles are typically 11.1V to 22.2V, while the required voltage for the radio system components is 6.0V to 7.4V depending on their ratings. Current draw with some of these systems normally ranges from 3A to 6A, as well. Some electronic speed controls in the R/C industry have this capability, but many do not, and it is a common point of failure for those that do.
This circuit provides the necessary regulation and power supply for high powered R/C systems common today. The center of the circuit is the RT8298, a synchronous high voltage Buck Converter that can support the input voltage range from 4.5V to 24V and the output current can be up to 6A. The voltage dividers that set the output voltage to 6V or 7.4V are controlled by a simple switch that the user sets to the voltage they want.
R/C Car Voltage Regulator – [Link]