Simple 5V POWER SUPPLY USING 7805 IC FROM 230V AC MAINS

This is the Simple 5V POWER SUPPLY USING 7805 IC FROM 230V AC MAINS circuit Diagram.Almost all digital circuits are works under 5V power supply. Here we are going to discuss on How to Generate  5V from 230V A.C supply. Digital IC’s, Microcontrollers, MicroProcessors and some basic circuits are generally powered by a 5V DC voltage. By using this project, you can eliminate the need of a battery in common circuitries. The circuit is simple to construct and maintain as it includes the following parts:-

COMPONENTS USED

Transformer  9V/2A  1

Regulator IC  7805  1

Diodes   1N4007  4

Capacitor   470uF,50V 1

           0.01uF  2


Simple 5V POWER SUPPLY USING 7805 IC FROM 230V AC MAINS

Working Principle of 5V Voltage Source


The circuit consisting of a 9V stepdown transformer, voltage regulator IC(7805) and some capacitors, used for filtering purpose. The figure given below shows the basic block diagram of AC to DC Converter. It includes the following stages:-

• Transformer
• Rectifier
• Filter
• Voltage Regulator

The stepdown transformer, down-converts the high voltage AC input (230V,50Hz) to a 9V,2A; because the transformer we used here having a specification of 9V/A. The alternating voltage from secondary terminal of the transformer is given to a bridge rectifier.

The bridge rectifier converts alternating voltage to unidirectional voltage with the switching action of diodes. This voltage is finally fed to a 5V regulator IC through a 470uF,50v electrolytic capacitor, which eliminates the ripples and make the output stable. After regulation we get a 5V DC voltage at the output of 7805 IC.

Read More

6V to 12V Converter Circuit Diagram

This inverter circuit can provide up to 800mA of 12V power from a 6V supply. For example, you could run 12V car accessories in a 6V (British?) car. The circuit is simple, about 75% efficient and quite useful. By changing just a few components, you can also modify it for different voltages.

Read : 250 to 5000 watts PWM DC/AC 220V Power Inverter

Notes

• L1 is a custom inductor wound with about 80 turns of 0.5mm magnet wire around a toroidal core with a 40mm outside diameter.
• Different values of D3 can be used to get different output voltages from about 0.6V to around 30V. Note that at higher voltages the circuit might not perform as well and may not produce as much current. You may also need to use a larger C3 for higher voltages and/or higher currents.
• You can use a larger value for C3 to provide better filtering.
• The circuit will require about 2A from the 6V supply to provide the full 800mA at 12V.

6V to 12V Converter Circuit Diagram

Parts
R1, R4 2 2.2K 1/4W Resistor
R2, R3 2 4.7K 1/4W Resistor
R5 1 1K 1/4W Resistor
R6 1 1.5K 1/4W Resistor
R7 1 33K 1/4W Resistor
R8 1 10K 1/4W Resistor
C1,C2 2 0.1uF Ceramic Disc Capacitor
C3 1 470uF 25V Electrolytic Capcitor
D1 1 1N914 Diode
D2 1 1N4004 Diode
D3 1 12V 400mW Zener Diode
Q1, Q2, Q4 3 BC547 NPN Transistor
Q3 1 BD679 NPN Transistor
L1 1 See Notes
MISC 1 Heatsink For Q3, Binding Posts (For Input/Output), Wire, Board

Sourced By:  circuitsdiagram-lab

Read More

USB Converter Circuit Diagram

Does this sound familiar: you buy a small piece of equipment, such as a programming & debugging interface for a microcontroller, and you have to use a clunky AC wall adapter to supply it with power? It’s even worse when you’re travelling and there’s no mains socket anywhere in sight. Of course, you can use the USB bus directly as a power source if the supply voltage is 5 V. If you need a higher voltage, you can use the USB converter described here. This small switch-mode step-up converter can generate an output voltage of up to 15 V with a maximum output current of 150 mA.

The LM3578 is a general-purpose switchmode voltage converter. Figure 1 shows its internal block diagram. Here we use it as a step-up converter. The circuit diagram in Figure 2 shows the necessary components. Voltage conversion is achieved by switching on the internal transistor until it is switched off by the comparator or the current-limiting circuit. The collector current flows through coil L1, which stores energy in the form of a magnetic field. When the internal transistor is switched off, the current continues flowing through L1 to the load via diode D1. However, the voltage across the coil reverses when this happens, so it is added to the input voltage. The resulting output voltage thus consists of the sum of the input voltage and the induced voltage across the coil.

The output voltage depends on the load current and the duty cycle of the internal transistor. Voltage divider R5/R6 feeds back a portion of the output voltage to the comparator in the IC in order to regulate the output voltage. C5 determines the clock frequency, which is approximately 55 kHz. Network R4, C2 and C3 provides loop compensation. The current-sense resistor for the current-limiting circuit is formed by three 1-Ω resistors in parallel (R1, R2 and R3), since SMD resistors with values less than 1 Ω are hard to find. The output voltage ripple is determined by the values and internal resistances of capacitors C11, C8, C7 and C6.

 

The total effective resistance is reduced by using several capacitors, and this also keeps the construction height of the board low. L2, C1, C9 and C10 act as an input filter. Ensure that the DC resistance of coil L2 is no more than 0.5 Ω. Use a Type B PCB-mount USB connector for connection to the USB bus.  A terminal strip with a pitch of 5.08 mm can be used for the output voltage connector. Of course, you can also solder a cable directly to the board. Two additional holes are provided in the circuit board for this purpose. As we haven’t been able to invent a device that produces more energy than it consumes, you should bear in mind that the input current of the circuit is higher than the output current. As a general rule, you can assume that the input current is equal to the product of the output current and the output voltage divided by the input R5 and R6 for other output voltages:

6V:	R5 = 47k, R6 = 9,1k
12V:	R5 = 110k, R6 = 10k
15V:	R5 = 130k, R6 = 9,1k

voltage and divided again by 0.8. Specifically, with an output current of 100 mA at 9 V, the input current on the USB bus is approximately 225 mA. Finally, Figure 3 shows a small PCB layout for the circuit. All of the components except the connector and the terminal strip are SMDs.

Parts List:

(for UO = 9 V)
Resistors
R1,R2,R3 = 1Ω
R4 = 220kΩ
R5 = 82kΩ
R6 = 10kΩ
Capacitors
(SMD 1206)
C1 = 100nF
C2 = 2nF2
C3 = 22pF
C4 = 100nF
C5 = 1nF5
(tantalum SMD 7343)
C6 = 68μF 20V
C7 = 68μF 20V
C8 = 68μF 20V
C9 = 47μF 16V
C10 = 47μF 16V
C11 = 68μF 20V
Inductors
L1 = 820μH (SMD CD105)
L2 = 47μH (SMD 2220)
Semiconductors
D1 = SK34SMD (Schottky)
IC1 = LM3578AM (SMD SO8)
Miscellaneous
K1 = 2-way PCB terminal block, lead pitch 5mm
(optional)
K2 = USB-B connector

Read More

12-V Glow Plug Converter Circuit Diagram

Most small internal-combustion engines commonly used in the model-building world use glow plugs for starting. Unfortunately, glow plugs have an operating voltage of 1.5 V, while fuel pumps, starter motors, chargers and the like generally run on 12 V. This means that a separate battery is always needed to power the glow plug. The standard solution is to use an additional 2-V lead storage battery, with a power diode in series to reduce the voltage by approximately 0.5 V. However, this has the annoying consequence that more than 30 percent of the energy is dissipated in the diode. Naturally, this is far from being efficient. 

12-V Glow Plug Converter Circuit Diagram

The converter presented here allows glow plugs to be powered from the 12-V storage battery that is usually used for fuelling, charging, starting and so on. A car battery can also be used as a power source. Furthermore, this circuit is con-siderably more efficient than the approach of using a 2-V battery with a series power diode. 

The heart of the DC/DC converter is IC1, a MAX 1627. The converter works according to the well-known step-down principle, using a coil and an electrolytic capacitor. Here the switching stage is not integrated into the IC, so we are free to select a FET according to the desired current level. In this case, we have selected a 2SJ349 (T1), but any other type of logic-level FET with a low value of RDSonwould also be satisfactory. Of course, the FET must be able to handle the required high currents. 

Diode D1 is a fast Schottky diode, which must be rated to handle the charging currents for C2 and C3. This diode must also be a fairly hefty type. The internal resistances of coil L1 and capacitors C2 and C3 must be as low as possible. This ensures efficient conversion and prevents the components from becoming too warm.

The resistor network R2/R3 causes 87 percent of the output voltage to be applied to the FB pin of IC1. This means that an output voltage of 1.5 V will cause a voltage of approximately 1.3 V to be present at the FB pin. The IC always tries to drive the switching stage such that it ‘sees’ a voltage of 1.3 V on the FB input. If desired, a different output voltage can be provided by modifying the values of R2 and R3. 

When assembling the circuit, ensure that C5 and C1 are placed as close as possible to IC1, and use sufficiently heavy wiring between the 12-V input and the 1-5-V output, since large cur-rents flow in this part of the circuit. A glow plug can easily draw around 5 A, and the charging current flowing through the coil and into C2 and C3 is a lot higher than this!

Author : P. Goossens

Read More

Low-Cost Step-Down Converter With Wide Input Voltage Range

The circuit described here is mostly aimed at development engineers who are looking for an economical step-down converter which offers a wide input voltage range. As a rule this type of circuit employs a step-down converter with integrated switching element. However, by using a more discrete solution it is possible to reduce the total cost of the step-down converter, especially when manufacturing in quantity. The TL5001A is a low-cost PWM controller which is ideal for this project. The input voltage range for the step-down converter described here is from 8 V to 30 V, with an output voltage of 5 V and a maximum output current of 1.5 A.

When the input voltage is applied the PWM output of IC1 is enabled, taking one end of the voltage divider formed by R1 and R2 to ground potential. The current through the voltage divider will then be at most 25 mA: this value is obtained by dividing the maximum input voltage (30 V) minus the saturation voltage of the output driver (2 V) by the total resistance of the voltage divider (1.1 kΩ). T1 and T3 together form an NPN/PNP driver stage to charge the gate capacitance of P-channel MOSFET T2 as quickly as possible, and then, at the turn-off point, discharge it again.

The base-emitter junction of T3 goes into a conducting state when the PWM output is active and a voltage is dropped across R2. T3 will then also conduct from collector to emitter and the gate capacitance of T2 will be discharged down to about 800 mV. The P-channel MOSFET will then conduct from drain to source. If the open-collector output of the controller is deactivated, a negligibly small current flows through resistor R2 and the base of T1 will be raised to the input voltage level. The base-emitter junction of T1 will then conduct and the gate capacitance of T2 will be charged up to the input voltage level through the collector and emitter of T1.

The P-channel MOSFET will then no longer conduct from drain to source. This driver circuit constructed from discrete components is very fast, giving very quick switch-over times. Diodes D2 and D3 provide voltage limiting for the P-channel MOSFET, whose maximum gate-source voltage is 20 V. If the Zener voltage of diode D2 is exceeded it starts to conduct; when the forward voltage of diode D3 is also exceeded, the two diodes together clamp the gate-source voltage to approximately 19 V. The switching frequency is set at approximately 100 kHz, which gives a good compromise between efficiency and component size.

Finally, a few notes on component selection. All resistors are 1/16 W, 1 %. Apart from electrolytic C1 all the capacitors are ceramic types. For the two larger values (C2 and C5) the following are used:

• C2 is a Murata type GRM21BR71C105KA01 ceramic capacitor, 1 µF, 16 V, X7R, 10 %;
• C5 is a Murata type GRM32ER60J476ME20 ceramic capacitor, 47 µF, 6.3 V, X5R, 10 %. D1 (Fairchild type MBRS340T3) is a 40 V/3 A Schottky diode. Coil L1 is a Würth WE-PD power choke type 744771147, 47 µH, 2.21 A, 75 mΩ.
• T1 (BC846) and T3 (BC856) are 60 V, 200 mA, 310 mW complementary bipolar transistors from Vishay. The TL5001AID (IC1) is a low-cost PWM controller with an open-collector output from Texas Instruments.

Read More

Short-Wave Converter Circuit Diagram

This short-wave converter, which doesn’t have a single coil requiring alignment, is intended to enable simple medium-wave receivers to be used to listen to short-wave signals. The converter transforms the 49-m short-wave band to the medium-wave frequency of 1.6 MHz. At the upper end of the medium-wave band, select an unoccupied frequency that you want to use for listening to the converted short-wave signals. Good reception performance can be obtained using a wire antenna with a length of one to two metres.

The converter contains a free-running oscillator with a frequency of around 4.4 MHz, which is tuned using two LEDs (which act as variable-capacitance diodes!) and a normal potentiometer. The frequency range is set by adjusting the emitter current using a 1k trimpot. The oscillator frequency depends strongly on the operating point. This is due to the combination of using an audio transistor and the extremely low supply voltage. Under these conditions, the transistor capacitances are relatively large and strongly dependent on the operating point. The second transistor forms the mixer stage.

If you calculate the resonant frequencies of the tuned circuits, you will obtain 6.7 MHz for the antenna circuit and 1.7 MHz for the output circuit. Additional transistor capacitance and the effects of the coupling capacitors shift each of the resonant frequencies downward. The tuned circuits are relatively heavily damped to obtain bandwidths that are large enough to allow the circuit to be used without any specific alignment. The results are good despite the low collector–emitter voltage of around only 0.6 V, due to the fact that only a modest amount of mixer gain is necessary. The entire circuit also draws less than 1mA.

Read More

12-9 Volt DC to DC Converter BD139 Circuit Diagram

This circuit is a DC voltage output from a small DC input generate large voltage.It ‘s easy and quick to do, and reducing the value of the Z-diode, the circuit can be universally adapted to other output devices of the circuit voltages. The give and all diagrams represent a DC converter with 12V battery 9 volt DC input and output.
  
12-9 Volt DC to DC Converter Circuit Diagram

With the 10V zener diode, as in the diagram, the output voltage is approximately 9.3 volts DC. The supply voltage is used, should always be at least a few volts higher than the Zener voltage. In this example, I have a 12 Volt DC battery to provide regulated 9-volt DC output.

Read More

12V Step-Down Dc Converter Using ADP2300 ADP2301

Using ADP2300 ADP2301 step-down dc dc regulators with integrated power MOSFET, can be designed a very simple DC DC voltage converter. Output voltage delivered by these circuits can be adjusted from 0.8 volts, up to 0.85xVin , with ±2% accuracy. The maximum output current that can be provided by ADP2300 ADP2301 regulators is up to 1.2 A load current.

12V Step-Down Dc Converter Circuit Diagram

There are two frequency options: the ADP2300 runs at 700 kHz, and the ADP2301 runs at 1.4 MHz. These options allow users to make decisions based on the trade-off between efficiency and total solution size. Current-mode control provides fast and stable line and load transient performance.  Bellow you an see two design examples, which require few common electronic components.First circuit will provide a 2.5V output at a maximum current of 1.2A from an input voltage of 12 volts. Second circuit will provide a 5V output at a maximum current of 1.2A from an input voltage of 12 volts.

Read More

12V to 9V DC Converter Circuit Diagram

To get a more precise output voltage, replace zener diode Z1 with 10V and R1 with a 1Kilo ohm potentiometer. A Coolrib for Q1 is optional but highly recommended. You can replace Q1 for a more robust type to get more output amps depending on your requirements. Simple circuit to power your 9 volt cassette recorder and other stuff.

Parts List:

R1 = 560 ohm
C1 = 1000uF/40V, Electrolytic
C2 = 10uF/25V, Electrolytic
C3 = 330nF, Ceramic
Z1 = 9.1V, 1watt zener
Q1 = ECG184, NTE184 

Read More

VGA to BNC Adapter Converter Circuit Diagram

This is the VGA to BNC Adapter Converter Circuit Diagram. There are monitors which only have three BNC inputs and which use composite synchronization (‘sync on green’). This circuit has been designed with these types of monitor in mind. As can be seen, the circuit has been kept very simple, but it still gives a reasonable performance. The principle of operation is very straightforward. The RGB signals from the VGA connector are fed to three BNC connectors via AC-coupling capacitors. These have been added to stop any direct current from entering the VGA card. A pull-up resistor on the green output provides a DC offset, while a transistor (a BS170 MOSFET) can switch this output to ground. It is possible to get synchronisation problems when the display is extremely bright, with a maximum green component.

In this case the value of R2 should be reduced a little, but this has the side effect that the brightness noticeably decreases and the load on the graphics card increases. To keep the colour balance the same, the resistors for the other two colors (R1 en R3) have to be changed to the same value as R2. An EXOR gate from IC1 (74HC86) combines the separate V-sync and H-sync signals into a composite sync signal. Since the sync in DOS-modes is often inverted compared to the modes commonly used by Windows, the output of IC1a is inverted by IC1b. JP1 can then by used to select the correct operating mode. This jumper can be replaced by a small two-way switch, if required.

VGA to BNC Adapter Converter Circuit Diagram

 

VGA to BNC adapter PCB layout

 This switch should be mounted directly onto the PCB, as any connecting wires will cause a lot of interference. The PCB has been kept as compact as possible, so the circuit can be mounted in a small metal (earthed!) enclosure. With a monitor connected the current consumption will be in the region of 30 mA. A 78L05 voltage regulator provides a stable 5 V, making it possible to use any type of mains adapter, as long as it supplies at least 9 V. Diode D2 provides protection against a reverse polarity. LED D1 indicates when the supply is present. The circuit should be powered up before connecting it to an active VGA output, as otherwise the sync signals will feed the circuit via the internal protection diodes of IC1, which can be noticed by a dimly lit LED. This is something best avoided.  

Resistors: 

R1,R2,R3 = 470Ω 

R4 = 100Ω 

R5 = 3kΩ3 

Capacitors: 

C1,C3,C5 = 47µF 25V radial 

C2,C4,C6,C7,C10 = 100nF ceramic 

C8 = 4µF7 63V radial 

C9 = 100µF 25V radial 

Semiconductors: 

D1 = LED, high-efficiency

D2 = 1N4002

T1 = BS170
IC1 = 74HC86
IC2 = 78L05

Miscellaneous:
JP1 = 3-way pinheader with jumper
K1 = 15-way VGA socket (female), PCB mount (angled pins)
K2,K3,K4 = BNC socket (female), PCB mount, 75Ω

Read More

1.5V to 5V/12V DC/DC Converter with LT1073 Project

This is the 1.5V to 5V/12V DC/DC Converter with LT1073 Project. Small 1.5V to 5V or 12V DC/DC converter with LT1073 chip. The IC is available in three different versions, depending on output voltage. Two with fixed output voltage of 5V and 12V, and the most interesting that can be adjusted. The adjustment is done through a voltage divider with two resistors, of mass, output and Terminal 8, internally connected to the voltage comparator IC, which is responsible for stabilizing the output voltage.

LT1073 has an internal everything you need to make a small DC / DC converter with a low operating voltage of only 95μA 1V and consumption without load.

If you do not have a meter inductance, the inductive part of the drive is a bit more complicated to make, but we shall see some possible solutions. Capacitor also recommended by the manufacturer for the circuit is a bit hard to get, I have used a tantalum recovered from another power source, and the ripple voltage at the output is quite low. Last but not least, say that the diode has to be a fast, not worth as the 1N4002 rectifiers, the 1N5818 is recommended schottky type, characterized by high response time and low internal resistance, which is what ideal for this type of converters.

As we can see from the photograph of the circuit in a low energy lamp, ay a small toroidal core can be recovered. 82μH To this core, we winding 7 turns of 0.3mm enamelled copper wire.

Another option is to use a toroidal core Ferroxcube, Farnell code 178-504 of 13.25 x7, 35x5, 7mm, grade 3C85, value AL 1000. with this core we have winding 8 turns to 90μH.

Finally, note that you can download the documentation in the manufacturer's website, is very good and complete, with numerous examples of applications, and above all very clear.

Read More

Low Cost Step Down Converter Circuit Diagram

The circuit described here is mostly aimed at development engineers who are looking for an economical step-down converter which offers a wide input volt-age range. As a rule this type of circuit employs a step-down converter with integrated switching element. However, by using a more discrete solution it is possible to reduce the total cost of the step-down converter, especially when manufacturing in quantity. The TL5001A is a low-cost PWM controller which is ideal for this project.

Low Cost Step Down Converter with Wide Input Voltage Range

The input voltage range for the step-down converter described here is from 8 V to 30 V, with an output voltage of 5 V and a maximum output current of 1.5 A. 

When the input voltage is applied the PWM output of IC1 is enabled, taking one end of the voltage divider formed by R1 and R2 to ground potential. The cur-rent through the voltage divider will then be at most 25 mA: this value is obtained by dividing the maximum input voltage (30 V) minus the saturation voltage of the output driver (2 V) by the total resistance of the voltage divider (1.1 kΩ). T1 and T3 together form an NPN/PNP driver stage to charge the gate capacitance of P-channel MOSFET T2 as quickly as possible, and then, at the turn-off point, discharge it again. The base-emitter junction of T3 goes into a conducting state when the PWM output is active and a voltage is dropped across R2. T3 will then also conduct from collector to emitter and the gate capacitance of T2 will be discharged down to about 800 mV. The P-channel MOSFET will then conduct from drain to source. If the open-collector output of the controller is deactivated, a negligibly small current flows through resistor R2 and the base of T1 will be raised to the input voltage level. 

The base-emitter junction of T1 will then conduct and the gate capacitance of T2will be charged up to the input voltage level through the collector and emitter ofT1. The P-channel MOSFET will then no longer conduct from drain to source. This driver circuit constructed from discrete components is very fast, giving very quick switch-over times. 

Diodes D2 and D3 provide voltage limiting for the P-channel MOSFET, whose maximum gate-source voltage is 20 V. If the Zener voltage of diode D2 is exceeded it starts to conduct; when the forward voltage of diode D3 is also exceeded, the two diodes together clamp the gate-source voltage to approximately 19 V. The switching frequency is set at approximately 100 kHz, which gives a good compromise between efficiency and component size. 

Finally, a few notes on component selection. All resistors are 1/16 W, 1 %. Apart from electrolytic C1 all the capacitors are ceramic types. For the two larger values (C2 and C5) the following are used:

• C2 is a Murata type GRM21BR71C105KA01 ceramic capacitor, 1 µF, 16 V, X7R, 10 %;.
• C5 is a Murata type GRM32ER60J476ME20 ceramic capacitor, 47 µF, 6.3 V, X5R, 10 %.
• D1 (Fairchild type MBRS340T3) is a 40 V/3 A Schottky diode. Coil L1 is a Würth WE-PD power choke type 744771147, 47 µH, 2.21 A, 75 mΩ.
• T1 (BC846) and T3 (BC856) are 60 V, 200 mA, 310 mW complementary bipolar transistors from Vishay.
• The TL5001AID (IC1) is a low-cost PWM controller with an open-collector output from Texas Instruments. Source by Link

Read More

12V From USB Port - 5V to 12V Converter Circuit Diagram

This is the 12V From USB Port - 5V to 12V Converter Circuit Diagram. Using this circuit we can convert 5V DC from the computer USB port to 12V DC and a circuit like this will find a lot of application in USB powered systems. The heart of this circuit is IC LT1618 which is a constant current, constant voltage boost converter. The IC has a wide input voltage range of 1.8 to 18V DC and output voltage can be up to 35V DC.

In the circuit resistors R1, R2 sets the output voltage. Pin number 9 is the shutdown pin, less than 0.3V to this pin will shut down the IC. Pin number four is the current sense adjust pin. The current sense voltage can be reduced by applying a DC voltage to this pin. If this adjustment is not needed connect this pin to ground and you can omit components R3, R5 and Q1.

Circuit Diagram

Notes

• C2 and C3 must be rated at least 15V.
• Less than 0.3V at the shutdown pin will shutdown the IC.
• Output voltage is governed by the following equation R1 = R2 (  (Vout /1.263V) -1).

Read More

LTC3601 3.3V DC Power Converter Circuit Diagram

This Dc power converter circuit is designed LTC3601 from Linear Technology and is capable to up to 1.5A output current at a 3.3V. The LTC3601 operating supply voltage range is from 4V to 15V making it suitable for a wide range of power supply applications. The operating frequency of the LTC3601 buck regulator is programmable from 800kHz to 4MHz with an external resistor enabling the use of small surface mount inductors.

LTC3601 3.3V DC Power Converter Circuit Diagram

The LTC3601 buck regulator can operate in two modes: Burst Mode operation and forced continuous mode to allow the user to optimize output voltage ripple, noise, and light load efficiency for a given application.

Read More

LT3582-12 DC 5V to 12V DC Converter Circuit Diagram

Using LT3582-12 dual channel DC DC converter integrated circuit, manufactured by Linear Technology, can be designed a very simple step up dc converter. This 5 to 12V c converter electronic project provide both positive and negative outputs required in many biasing applications such as active matrix OLED (organic light-emitting diode)displays as well as CCD (charge coupled device) applications.

LT3582-12 DC 5V to 12V DC Converter Circuit Diagram

Read More

12V to 250V Converter Circuit Diagram

A very simple portable 12v to 250V converter can be designed using this circuit diagram. This 12 to 250V converter is designed for portable use with a 12 V car battery.A built astabil multivibrator T1 and T2 generates a rectangular wave at a frequency of 50 Hz. As T1 and T2 drive alternative exit stage system also works in "push-pull". When T1 lead by passing a current T3: T5 and that it engages the latter transistor connects to a half battery of 12 V secondary winding of the transformer Tr When T2 network drive, T6 transistor coupled to the battery the other half of the network adapter.

 If it is used for output stages 40 411 RCA transistors, the current through secondary winding can be up to 10 A, giving a power output of 180 watts. If you use 2N3055 transistors, power output will be about 90 watts. Since the output transistors are driven to saturation, they have very high mounted radiators.Although circuit is simple construction and has high efficiency disadvantage is rectangular output voltage which, in the absence of a regulator is dependent on task: small loads, the output voltage is 250 V ac (not working properly for the engine speed control, light dimmers, televisions, hi-fi equipment.

Read More

High Current Step-Up Converter Using MAX641

High Current Step-Up Converter Using MAX641 integrated circuit, manufactured by Maxim IC, can be designed a very simple step-up converter using few electronic components. This step-up high voltage converter electronic projects allows a maximum output current up to 1A.

High Current Step-Up Converter Circuit Diagram

Low battery voltage detector input compare LB1 with internal reference of 1.31 V. LBO output goes in low state when the voltage at pin 1 falls below 1.31 V. The threshold voltage for "low battery", is determined by voltage divider R1-R2.

LED D1 illuminates the LBO output when the input voltage falls below 2.62 V.
Input voltage must remain below 5 V. The maximum effectiveness is 80% conversion.

Read More

Analog to Digital Converter (ADC) Circuits Diagram

Normally analogue-to-digital con-verter (ADC) needs interfacing through a microprocessor to convert analogue data into digital format. This requires hardware and necessary software, resulting in increased complexity and hence the total cost. The circuit of A-to-D converter shown here is configured around ADC 0808, avoiding the use of a microprocessor.

The ADC 0808 is an 8-bit A-to-D converter, having data lines D0-D7. It works on the principle of successive approximation. It has a total of eight analogue input channels, out of which any one can be selected using address lines A, B and C. Here, in this case, input channel IN0 is selected by grounding A, B and C address lines. Usually the control signals EOC (end of conversion), SC (start conversion), ALE (address latch enable) and OE (output enable) are interfaced by means of a microprocessor. However, the circuit shown here is built to operate in its continuous mode without using any microprocessor.

Therefore the input control signals ALE and OE, being active-high, are tied to Vcc (+5 volts). The input control signal SC, being active-low, initiates start of conversion at falling edge of the pulse, whereas the output signal EOC becomes high after completion of digitization. This EOC output is coupled to SC input, where falling edge of EOC output acts as SC input to direct the ADC to start the conversion. 

Analog to Digital Converter (ADC) Circuit Diagram

As the conversion starts, EOC signal goes high. At next clock pulse EOC output again goes low, and hence SC is enabled to start the next conversion. Thus, it provides continuous 8-bit digital output corresponding to instantaneous value of analogue input. The maximum level of analogue input voltage should be appropriately scaled down below positive reference (+5V) level. 

 The ADC 0808 IC requires clock signal of typically 550 kHz, which can be easily derived from an astable multivibrator constructed using 7404 inverter gates. In order to visualize the digital output, the row of eight LEDs (LED1 through LED8) have been used, wherein each LED is connected to respective data lines D0 through D7. Since ADC works in the continuous mode, it displays digital output as soon as analogue input is applied. The decimal equivalent digital output value D for a given analogue input voltage Vin can be calculated from the relationship.

Read More

DC Converter DC 12V to 24V 2A Circuit Diagram

DC 12V to 24V 2A Circuit diagram energy converter 12V to 24V 2A, which uses the integrated circuit CD4093 and CD40106, and MOSFETs BUZ11 output. This converter can be used with some modifications as the source for Notebook charger, connecting equipment with voltage 24volts, etc.. For full operation of DC / DC converter input 12Volts must be a current of 4 amperes or more. 

 DC Converter  DC 12V to 24V 2A Circuit diagram

Read More

Converter RS232 to Arduino Circuit Diagram

The circuit in this article is an RS232 converter, it is possible to connect an Arduino bootloader or your chip with a RS232 port. Here are two versions, one very simple and functional above and one below a little more sophisticated. The port 232 gives a bit more work than USB, but in case of equipment that only have this feature that is a good outlet.

 Converter RS232 to Arduino Circuit Diagram

Read More