Battery Powered Plus-Minus 15v Supply - Many classic operational amplifier circuits call for a split positive and negative 15 volt supply. The circuit below makes the job of generating such a supply much easier by using an off-the-shelf DC to DC converter, powered from a cheap 6v battery made . . . Hobby Circuit designed by David Johnson P.E.-August, 2008
Beef up Voltage Regulators - Last month we learned how to make any fixed voltage regulator adjustable. However, many fixed regulators such as the 7805 limit their output current to 1.5 amps. While this may be adequate for many QRP transceivers, amateurs would often like to run a low power mobile 2 meter transceiver on their home-brew power supply. All that needs to be done is to add a couple of inexpensive pass transistors as in Figure 1 __ Designed by Radio Amateur Society of Norwich
Bench Top Power Supply Auto-Fan - The op-amp used is a readily available LM339. This IC contains four op-amps but we use only two of them. Use the others for spare or do something else with it. For the thermistor I used a small, very expensive ($52) , glass-encapsulated type because I had it laying around but almost any type will do. I experimented with a couple different types and they all worked __ Designed by Tony van Roon VA3AVR
Bench Top Power Supply, Auto-Fan - The op-amp used is a readily available LM339. This IC contains four op-amps but we use only two of them. Use the others for spare or do something else with it. For the thermistor I used a small, very expensive ($52) , glass-encapsulated type because I had it laying around but almost any type will do. I experimented with a couple different types and they all worked __ Designed by Tony van Roon VA3AVR
Bench Top Power Supply, Part 2 - in this second part of the Bench Top Power Supply project we will cover the construction, assembly, and wiring of the large Coolrib and the optional Automatic Fan Control circuit. When that is done the transformer T1, 115VAC components, large capacitor C3, and the bridge rectifier will be installed and wired up. There are lots of pictures and photos to help you out. Main thing to remember is to TAKE-it-EASY, read the explanations and take your time. This is definitely a NO rush job __ Designed by Tony van Roon VA3AVR
Bench Top Power Supply, Part 3 - Almost done! in this part three we install the final parts, make the last connections, and do the final adjustments with the trimmer pots. Take your time (go-slow) with the trimmer pots for adjusting current! . __ Designed by Tony van Roon VA3AVR
Bench Top Power Supply, Part 4 PICs - I have been asked several times to include more construction pictures and photos. Well here they are. A couple of them can be magnified to full size; just click on them. I will add photos of the shunts for the panel meters and associated calculations on a later date. in the mean time this will get you going for a while __ Designed by Tony van Roon VA3AVR
Bi-Directional Buck-Boost Supercapacitor Backup Supply - The LT8705 is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The part has integrated input current, input voltage, output current and output voltage feedback loops. With a wide 2.8V to 80V input and 1.3V to 80V output range, the LT8705__ Linear Technology/Analog Devices App Note, Feb 15th 2013
Bi-Directional Motor Speed Regulator - This circuit shows the concept I used in the drill motor control that I submitted earlier. I cam up with it in 1994 when I built the device. My algebra and my patience are a bit too rusty at my age now to write an equation that describes the relationship between the BEMF of the motor and Vin. __ Designed by Andrew R. Morris
Big Power for Big Processors: the LTC1430 Synchronous Regulator - DN113 Design Notes__ Linear Technology/Analog Devices
Boost Controller Drives Buck Converter - 02/03/97 EDN Design Ideas: By adding an external Switching Transistor, you can use a step up DC/DC Converter to step down voltages to produce an efficient Battery Powered Power Supply, this example Circuit can step down inputs as Low as2V to Outputs as Low as1.25V, with efficiency as high as 80% Design by Michael Keagy, Maxim Integrated Products, Sunnyvale, CA
Boost converter works with wide-range negative-Input supply - 18-Mar-04 EDN Design Ideas: Assume that a design requires positive voltage, but only a negative-voltage power source is available. Using a standard boost-converter IC in the circuit of Figure 1, you can efficiently generate a positive voltage from a negative source. The boost converter generates an output voltage that's higher than the input voltage Design by Mike Wong, Intersil Corp, Milpitas, CA
Boost Regulator Makes Low Profile SEPIC with Both Step-Up & Step-Down Capability - DN317 Design Notes __ Linear Technology/Analog Devices
Boosted LM317/LM337 Regulators - Transistors types have been altered to ones that are more readily available. __
Boosting Regulator Current - An outboard pass transistor used to increase the current output of a voltage regulator IC . __ Designed by Andy Collison
Bootstrapped Boost Converter operates at 1.8 Volt - 04/23/98 EDN Design Ideas: NOTE: File contains multiple circuits scroll to find this circuit. Many circuits, such as those that use batteries or solar cells, must operate in the face of decreasing supply voltages. The circuit in Figure 1 maintains the maximum load current as the supply voltage drops. The regulator boosts a 2.5 to 4.2V input to 5V Design by Tom Gross, Linear Technology, Milpitas, CA
Buck Converter Handles Battery-Backup System - 04/24/03 EDN Design Ideas: Circuit forms gamma-photon detector - A synchronous buck converter is inherently bidirectional. That is, it transfers energy from input to output as a buck regulator when the output voltage is low, but, when the output voltage is high, the converter acts as a boost regulator, transferring power from output to input. This design idea shows how to use this bidirectional energy transfer to automatically recharge a battery when the Design by Haresh Patel, Linear Technology Corp, Milpitas, CA
Buck converter works efficiently from phone line - 02/15/00 EDN Design Ideas: A switching converter provide as an inexpensive way to generate 5V, 18 mA (48V, 5 mA maximum) directly from a standard phone line (Figure 1). The high input voltage and low available current require a unique design approach to achieve high efficiency. The circuit uses the LM2597HVM, which has a 60V rating and power-saving features. Design by Wayne Rewinkel, National Semiconductor, Santa Clara, CA
Buck IC Boosts Battery Voltage for White LED - 04/24/03 EDN Design Ideas: White-light LEDs are finding their way into many markets that incandescent bulbs once served. Flashlights are among the newer applications in which reliability, ruggedness, and ability to control the power draw of the LEDs make these devices attractive. With incandescent bulbs, the power management for the device is a simple on-off switch Design by Robert Kollman, Texas Instruments, Dallas, TX
Buck Mode Switching Regulator for Solar Applications - The purpose of a voltage regulator circuit is to take a variable input voltage and produce a steady output voltage. Two common regulator types are linear and switch-mode. Linear regulators are simple, but waste a lot of power in the process of regulating the voltage. Linear regulators can be thought of as self adjusting series resistors. Switch-mode regulators such as this one are much more efficient. Switch-mode regulators convert DC input voltages to pulses of high voltage DC. The DC pulses are used to charge a storage capacitor to the desired output voltage. The voltage is regulated by varying the width of the DC pulse __ Designed by G. Forrest Cook
Buck or Boost: Rugged Fast 60V Synchronous Controller Does Both - DN370 Design Notes__ Linear Technology/Analog Devices
Buck Regulator & Two Inductors Make Dual-Polarity Converter - 20-Mar-03 EDN Design Ideas: A common problem for power-supply designers is to create a compact, dual-polarity step-down converter. if space and cost are not concerns, the obvious solution is a pair of DC/DC converters, one for each output. But space and cost are almost always issues for communications, data-acquisition, and disk-drive applications Design by Keith Szolusha, Linear Technology Corp, Milpitas, CA
Buck regulator controls white LED with optical feedback - 10/25/07 EDN-Video Design ideas - By using optical feedback, you can stabilize the output level of a high-intensity LED Design by Dhananjay V Gadre, Netaji Subhas Institute of Technology, New Delhi, India
Buck regulator forms high-power, inverting –5V supply - 04/01/04 EDN Design Ideas: Configuring a step-down switching-converter IC as an inverter yields an efficient, high-power, -5V supply that can of deliver currents as high as 4.5A at the 12V input or 3.2A at the 5V input (Figure 1). Conventional inverting power Design by Bruce Denmark, Maxim Integrated Products, Sunnyvale, CA
Buck Regulator Operates Without a Dedicated Clock - 08/21/03 EDN Design Ideas: Most switching regulators rely on a dedicated clock oscillator to determine the switching frequency of operation. A dedicated oscillator circuit within the power controller usually generates the clock signal. A class of hysteretic switching regulators can actually operate at a relatively fixed frequency without a clock, even with changing input-line and output-loading conditions Design by Robert Bell, National Semiconductor, Phoenix, AZ
Buck Regulator Terminates Fast Data Buses - 07/20/95 EDN Design Ideas: The limitations of 5 and 3.3V CMOS
buses are spurring the development of high-speed, low-voltage buses for the next generation of computers. These buses, such as Futurebus and Rambus, require low-voltage supply rails to reduce signal-voltage swings. Other buses, such as CTT (center-terminated transceiver) and HSTL (high-speed transceiver logic) , have center termination and, therefore, require a power source that can sink current as well as source it Design by Bruce Moore, Maxim Integrated Products, Sunnyvale, CA
Buck Regulator Uses Step-Up Controller - 11/09/95 EDN Design Ideas: The circuit in Fig 1uses a step-up (boost) DC/DC controller in a negative buck-regulator application. The circuit’s function is to power the laser diode in an optical amplifier/booster unit, a job for which no commercial IC is available. The anode of the laser diode connects to ground, so the supply voltage must be negative and must deliver 160 to 750 mA. Although the boost-regulator IC operates in a buck-regulator circuit, its standard connections permit proper control of Q1. However, you need an op amp Design by Massimo De Marco, Maxim Integrated Products Cusano Milanino, Italy
Buck Regulator with LDO Post Regulation for Low Noise & Ripple - The LT3070 is a low voltage, UltraFast transient response linear regulator. The device supplies up to 5A of output current with a typical dropout voltage of 85mV. A 0.01μF reference bypass capacitor decreases output voltage noise to 25μVRMS. The LT3070’s high bandwidth permits the use of low ESR ceramic capacitors, saving__ Linear Technology/Analog Devices App Note, Apr 22, 2011
Buck-Boost Regulator Suits Battery Operation - 09/04/03 EDN Design Ideas: A buck/boost converter can step a voltage up or down. Such a converter is appropriate for battery-powered applications. One application derives a regulated 14.1V at 1A from 12V solar panels with 9 to 18V variation. in this type of b Design by Kahou Wong, On Semiconductor, Phoenix, AZ
Buck-converter charger also provides system power - 05/22/97 EDN Design Ideas: Switching Regulator provide as charge voltage setpoint with Current regulation, and second Switching Regulator provide as5V System Power -Many systems require long-time operation during periods of power loss. Often, a gel or wet-cell lead-acid battery is best choice because of high capacity and relatively low cost. The battery charges __ Designed by Robert Hanrahan, National Semiconductor, Woodcliff Lake, NJ
Build a Digital Audio Millivoltmeter - Versatile unit indicates signal levels in mV, dBv & dbm. Want to measure small signals at audio frequencies? Here's a low-cost digital audio millivoltmeter which will allow you to measure audio signals from below 5Hz to above 100kHz. As well as indicating the level in both millivolts and dBV, it also shows the corresponding dBm level into 600 ohms.__ SiliconChip
Build a High Performance Voltage Regulator from Discrete Components - While integrated circuits have become a staple of all modern circuit designs, it is still possible to build circuits without IC ’s and still achieve a high level of performance. The circuit in Figure 1 is a high performance 5 volt voltage regulator built using discrete components that are readily available. I have used no IC ’s and I have even substituted a 1N4001 in lieu of a zener diode. The regulator output voltage varies by a mere .4% and has current limiting at 1.5 amps along with short circuit protection. With the exception of thermal shutdown, this circuit closely matches the performance of the 7805 5 volt regulator IC . __ Designed by N1HFX
Build a transformerless 12V-to-180V DC/DC converter - 8-Jul-04 EDN Design Ideas: Some transducers for portable or automotive applications need accurately regulated, high-voltage bias and draw little current. To produce such high voltages from a low battery voltage, designers typically use switch-mode DC/DC converters—generally, flyback converters. These converters exhibit high efficiency at medium or high output power Design by Francis Rodes, ENSEIRB/IXL, Talence, France
Build an Accurate Bipolar Voltage Reference - EDN-Design ideas -- 05/12/11 Use a precision amplifier to get a voltage reference from a single power supply. Pulse generators often need voltage comparators with accurately defined hysteresis, and such comparators need bipolar voltage references. Most voltage-reference-cell ICs are referenced to their low-side supply rail. if your circuit needs both positive and negative voltages, you could create the negative reference voltage by connecting a −1 gain inverter to the output of an IC reference cell. if your analog circuit runs from a single power supply, however, you must shift the common-mode voltage to a specific level. You can use the circuit in Figure 1 for that task. Design by Marián Štofka, Slovak University of Technology, Bratislava, Slovakia
Build your own laboratory precision voltage reference - 05/24/07 Video Design ideas-EDN Mark Thoren, mixed-signal application engineering manager with Linear Technology, demonstrates an amplifier-based Circuit design for a relatively inexpensive precision voltage source. Design by Mark Thoren, mixed-signal application engineering manager with Linear Technology
Build Your Own Laboratory Precision Voltage Source-LT1206, LT1881, LT1010, LT1017 - Every electronics lab needs a couple different types of voltage sources. Power supplies are the obvious choice, but these bench top supplies are not very stable over time and temperature, they cannot sink current and it can be very difficult to set an accurate voltage. This video gives a step-by-step demonstration of an amplifier __ Linear Technology/Analog Devices App Note, Mark Thoren-Applications Engineering Manager Jun 15th 2008
|