Electronics-Lab.com Blog

This SMPS boosts low voltage (5-20 volts) to the high voltage needed to drive nixie tubes (170-200 volts). Be warned: even though this small circuit can be operated on batteries/low voltage wall-worts, the output is more than enough to kill you! Project includes: Helper Spreadsheet EagleCAD CCT & PCB files MikroBasic Firmware Source

High Voltage Switch Mode Power Supply for Nixie Tubes – [Link]

Jacques VE2EMM writes:

With a maximum capacity of 20 volts and 1 amp, it will supply  most of your projects, it’s greatest quality is the protection all your projects,  it is capable of limiting the maximum current to as low as 1mA, saving your ICs and transistors in case of an accidental short  circuit during the experimenting period of your projects. It is also an excellent battery charger.

Building a workshop Power Supply: 0-20V/0-1A/CC-CV - [Link]

The TPS75003 is a triple voltage regulator for Xilinx Spartan-3(E) FPGAs. Farnell are now supplying these in low quantities.

The device has some quite specific external component requirements. As most of the components listed on the datasheet and appnotes seem to be only available in the US, this page lists suitable components available in the UK, via Farnell.

TPS75003 Spartan-3(E) Voltage Regulator - [Link]

Most engineers know that they can use an inexpensive, three-terminal adjustable regulator, such as Fairchild Semiconductor’s LM317, as an adjustable regulator to only some necessary value of voltage, such as 36 or 3V. This value cannot be less than 1.25V without employing other approaches, however. The devices’ inner reference voltage is 1.25V, and their output voltage accordingly cannot be less than this value without potential bias. One way to solve this problem is to use a reference-voltage source based on two diodes. Although this approach is suitable for a 1.2 to 15V or higher-voltage regulator, it is not appropriate for an extra-low-voltage fixed- or adjustable-voltage regulator. The two 1N4001 diodes it employs do not provide the needed potential bias of 1.2V, and they have additional temperature instability of approximately 2.5 mV/K.

Use an LM317 as 0 to 3V adjustable regulator – [Link]

There are two major types of backlights for LCDs: LEDs, which stands for light emitting diode, or EL, which stands for electroluminescent. EL backlights tend to be more efficient and have more uniform lighting than LED ones, but they require some tricky circuitry to drive. If you’ve heard of Organic LED displays, or OLEDs, that’s basically an array of electroluminescent strips shunk down to the size of individual pixels.

Build a LCD Backlight – Electroluminescent Inverter - [Link]

This kit combines an LM317 with a thumbwheel potentiometer to allow you to easily set the output voltage from 1.5V up to 2V less than the input. Three preset voltages (5, 9, 12V) can also be selected. Input power comes from an external source.

Features:

• Stable, low-noise output adjustable from 1.5 to 30V
• Supplies up to 500mA
• Preset outputs of 5V/9V/12V
• Integrated heatsink

A general purpose dc power supply KIT - [Link]

This circuit is suitable for a variety of uses. If you have a solar powered 12 Volt lead-acid battery power source, the circuit can be used to efficiently power lower voltage devices. It can be used to provide power to devices that normally use a set of small batteries for power. Common voltages such as 1.5V, 3V, 4.5V, 6V, 7.5V, and 9V can be produced by this circuit. The circuit has been used to power small fans, portable radios, a miniature TV, and more.

Buck Mode Switching Regulator for Solar Applications - [Link]

The schematics for this DC/DC converter is built around the UC3843 generic, low cost PWM controller. This very common PWM controller generate a duty-cycle modulated square wave ranging from 0 to 100%, at a user fixed frequency of 100KHz.Here are some features: [via]

• Input voltage from 10V to 18V
• Output voltage from 20V to 28V adjustable
• Output current up to 5A for 3300mAh battery packs fast charge.
• Compact dimension (80×60mm)
• No heat sink or fan coolers even delivering up to 140W to the load.

High power 24V DC/DC converter - [Link]

Simple negative power supply (-5V / -12V / -15V) Sometimes you need a simple negative power supply. The best example is the contrast PSU for common small LCD device. Building -5V from a battery or a wallmart supply isn’t really easy.Here is a simple design small device that is able to provide -5V, -12V, -15V. He used the MAX 764/765/766 series. [via]

Simple negative power supply (-5V / -12V / -15V) - [Link]

Ralph W5JGV writes:This is an ongoing narrative of my attempt to construct a high-power switching power supply to replace the failed power supply in my Heath Warrior amplifier. Since I use the amplifier for experimental (non-Ham) work, it sometimes has to operate at full CW power for several hours at a time. The original plate transformer is unsuitable for that task, so I am attempting to build a really heavy-duty supply to replace the original power supply.My design concept started when I inherited a large quantity of well-built Dell computer power supplies. They were rated for 230 watts, and some testing showed that the switching transformers in the supplies could easily handle 250 watts. Hmm… If there was just a way that I could make these things put out HV instead of +5 Volts, I’d be all set. Well, to work! [via]

Experimental KW Switching Power Supply - [Link]