Showing posts with label Switched-Mode PS. Show all posts

Friday, April 14, 2023

Mini Switching Power Supply 5V - 25V, 3A with TNY268 and PCB

Electronic Circuits Circuits to Assemble , Electronic Circuits

Mini Switching Power Supply 5V - 25V, 3A with TNY268 and PCB

Para Versão em Portugues, clique aqui!

In this article, we will be discussing a mini switched power supply that provides 5V to 25Vdc output. This power supply is perfect for various electronic devices that require a stable and reliable power supply.

This is a power supply based on the TNY268 Integrated Circuit, which is part of a series of TinySwitch-II circuits: TNY263, TNY264, TNY265, TNY266, TNY267 and TNY268.

For a Flyback-type switched power supply like the one proposed, this IC is ideal, it integrates in its encapsulation the components necessary for it to work:

PWM Control, Power Mosfets
Overcurrent Protection
Over-Temperature Protection
Self-Feeding System

It does not need auxiliary windings, which makes it a complete IC, with DIP8 encapsulation, with a PWM working frequency of 132kHz and a voltage of up to 700V.

We will dive into the technical specifications, design, and features of this power supply and how it compares to other similar products in the market.

Technical Specifications

The mini switched power supply has an input voltage range of 80V to 260V AC, which makes it suitable for use in different parts of the world.

It provides an output voltage that can be regulated between 5V to 25V, with a current of up to 3A, depending on the configuration that we choose.

The power supply also has short-circuit protection and overvoltage protection, ensuring the safety of the connected devices.

Design

The mini switched power supply has a compact design, with dimensions of 55mm x 26mm x 21mm. The power supply is enclosed in a plastic case that protects the circuitry from dust and other environmental factors.

The power supply has a standard WJ2EDGVC-5.08-2P connector, making it easy to connect different electronic devices.

Caution!

"This circuit works directly connected to the electrical network, this is extremely dangerous, any carelessness, or wrong connections, design error, or any other occasion, can lead to irreversible damage.

We are not responsible for any type of occurrence. If you don't have enough experience, don't build this circuit, and if you build it, when testing it, be sure to have the proper protections and be accompanied by someone else."

Features

One of the standout features of this mini switched power supply is its efficiency. It has a high efficiency rating of up to 85%, which means that it wastes less energy as heat compared to other similar products.

This feature is especially important for electronic devices that are battery-powered, as it helps to extend their battery life.

Another feature of this power supply is its low ripple and noise. The power supply has a ripple voltage of less than 50mV, which ensures that the connected devices receive a stable and noise-free power supply.

This is especially important for audio devices, where any noise in the power supply can cause unwanted noise in the audio output.

TNY268 - Pinout and Description

The TNY268 is packaged in a DIP-8B structure for perforated pinouts and an SMD-8B package for SMD.

The package is similar to the well-known IC LM555, with the exception of pin 6 hidden in the TNY268, as we can see in the pinout of Figure 2, below.

Fig. 2 - Pinout - Pinout TNY268

We leave below the description of each pin of the TNY268 Integrated Circuit to facilitate our understanding.

DRAIN (D): Power MOSFET drain connection. Provides internal operating current for start-up and steady-state operation.
BYPASS (BP): Connection point for an external 0.1 µF bypass capacitor for the internally generated 5.8 V supply.
ENABLE/UNDERVOLTAGE (EN/UV): This pin has two functions: input enable and line undervoltage detection. During normal operation, power MOSFET switching is controlled by this pin. MOSFET switching is terminated when a current greater than 240 μA is drawn from this pin.

This pin also detects line undervoltage conditions through an external resistor connected to the DC line voltage. If there is no external resistor connected to this pin, TinySwitch-II detects its absence and disables the line undervoltage function.
SOURCE (S): Common control circuit, connected internally to the output MOSFET source.
SOURCE (HV RTN): MOSFET source connection output for high voltage feedback.

The Switched Power Supply Circuit

The Mini Switched Power Supply Circuit with TNY268 for 5V - 24V, 3A output is a simple yet powerful design, as shown in Figure 3 below.

However, due to the involvement of electricity, it requires careful handling and at least intermediate knowledge of electronics to assemble the circuit.

Fig. 3 - Schematic Diagram Mini Switching Power Supply 5V - 25V, 3A with TNY268

The schematic diagram of the Mini Switched Power Supply Circuit is well laid out and easy to understand. It includes a TNY268 controller that regulates the output voltage and current of the power supply.

The circuit has a few essential components such as capacitors, resistors, diodes, and an inductor, which work together to provide stable and efficient power.

Regulate The Output Voltage

The output voltage is adjusted through two parameters in the circuit:

The D4 diode, which is a 1W Power Zener diode.
The secondary winding of the transformer.

The Zener Diode

The zener diode D4, is the diode that will adjust the output voltage, we must configure it as follows,

when the desired voltage is Xv, the zener diode must have a voltage Xv - 1.

The diode should be 1V lower than the nominal voltage of the power supply, this lower voltage is due to the photocoupler being connected in series with the zener diode, and since it is an “LED” diode, we have the voltage drop on it.

For example:

To obtain a voltage of 5V at the power supply output:

The zener diode D4 = 4V. We use a commercial 4.3V, 1N4731 zener diode.

To obtain a voltage of 9V at the power supply output:

The zener diode D4 = 8V. We use a commercial 8.2V, 1N4738 zener diode.

To obtain a voltage of 12V at the power supply output:

The zener diode D4 = 11V. We use a commercial 11V, 1N4741 zener diode.

To obtain a voltage of 25V at the power supply output:

The zener diode D4 = 24V. We use a commercial 24V, 1N4749 zener diode.

The Transformer

The transformer used in this circuit was a high frequency transformer, often found in PC power supplies, as illustrated in Figure 4 below, a model EE-25 Ferrite transformer.

Fig. 4 EE-25 Ferrite Transformer

Primary coil winding

The primary will be wound to support a voltage between 85V and 260V, and this will be done by winding 140 turns of 33AWG enamelled wire, or 0.18 mm diameter wire.

Right after winding the primary, place appropriate insulation tape, with electrical and thermal insulation, to insulate the primary from the secondary.

Secondary coil winding

The secondary will be wound according to the desired output voltage, and this will be done in such a way that, for each desired 1V, 1.4 turns of 17AWG enameled wire or 1.15 mm wire are wound.

The calculation for an output voltage of 5V can be achieved using the formula below:

Formula: N = V * F

N = Number of Turns
V = Desired Voltage
C = Constant = 1.4

V = 5V
C = 1.4
N = ?

N = 5 * 1.4
N = 7 laps

For 5V on the output, we have 7 turns to wind in the secondary.

The calculation for an output voltage of 9V:

V = 9V
F = 1.4
N = ?
N = 9 * 1.4
N = 12.6 = ~13 Rounds

For 9V on the output, we have 13 turns to wind in the secondary.

The calculation for an output voltage of 12V:

V = 12V
F = 1.4
N = ?
N = 12 * 1.4
N = 16.8 = ~17 Rounds

For 12V output, we have 17 turns to wind in the secondary.

The calculation for an output voltage of 24V:

V = 25V
F = 1.4
N = ?
N = 25 * 1.4
N = 35 Turns

For 24V output, we have 37 turns to wind in the secondary.

The good thing is that with the formula, we can calculate any voltage we want to get at the output of our switching power supply.

Components list

Semiconductor

U1 ......... Integrated Circuit TNY268P
OPT....... TLP181 Opto-Coupler
D1, D2 ... Diode 1N4007
D3 ......... Fast Diode FR307
D4 ......... Zener Diode *See Text

Resistor

R1 .... Resistor 10Ω / 1W (brown, black, black, gold)
R2 .... Resistor 200KΩ / 1/4W (red, black, yellow, gold)
R3 .... Resistor 470Ω / 1/4W (yellow, violet, brown, gold)

Capacitors

C1 ....... Electrolytic Capacitor 47uF/400V
C2 ....... Polyester Capacitor 2.2nF
C3 ....... Polyester Capacitor 100nF
C4 ....... Electrolytic Capacitor 470uF/35V

Several

T1 ......... EE-25 Ferrite Transformer
P1, P2 ... Connector WJ2EDGVC-5.08-2P
Others... PCI, Wires, Solders, Etc.

Printed Circuit Board - Download

In Figure 5 below, we are making the PCI available in GERBER, PDF and JPEG files, for those who want to create a more optimized assembly, either at home, or if you prefer, at a company that prints the board.

PCB-Mini Switching Power Supply 5V - 25V, 3A with TNY268

You can download the files for free from a direct link in the Download option below.

Click Here!

Conclusion

In conclusion, the mini switched power supply that provides a programable 5V to 25Vdc output is an excellent choice for various electronic devices. Its compact design, high efficiency, and low ripple and noise make it stand out compared to other similar products in the market.

Its safety features, such as short-circuit protection and overvoltage protection, ensure that connected devices are protected from damage. If you are looking for a reliable and efficient power supply for your electronic devices, then this mini switched power supply is a great choice.

You can see the official post by clicking here! fvml.com.br

If you have any questions, suggestions or corrections, please leave them in the comments, and we will answer them soon.

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My Best Regards!!!

Switched Power Supply SMPS 13.8V 10A using IR2153 IC and IRF840, with PCB

Electronic Circuits Circuits to Assemble , power supply

13.8V-SMPS-Power-Supply-Using-IR2153-IC-and-IRF840-Mosfet

Para Versão em Portugues, clique aqui!

Switched Power Supply SMPS 13.8V 10A using IR2153 IC and IRF840, with PCB

This circuit is a straightforward design for an SMPS power supply, utilizing the IR2153 IC. This chip, which has only 8 pins, functions as a PWM controller, enabling the creation of a high-performing and cost-effective unregulated switching power supply for basic projects.

The output voltage of this power supply is set at 13.8V and can be adjusted via the trimpot RV1. It also provides a steady current of 10A at its output.

The Circuit

The circuit basically consists of 8 main steps:

Protection Circuit: It comprises a 5A/250V fuse, which operates if there is a current greater than the fuse's breaking current.
At the same time we also have an NTC (Negative Temperature Coefficient), it is a surge current limiter, this same topology can be found in most SMPS power supplies, such as notebook power supplies, PC power supplies, computer AT / ATX power supplies, etc.
Transient Filter: This step consists of an initial capacitive filter that inhibits high frequencies from returning to the network, or vice versa, and soon after, the EMI filter coil, which serves to attenuate high frequency noise.
Primary Rectification: Made up of the D1 rectifier bridge.
Primary Filter: Composed of capacitors C4 and C5.
Switching: Composed of a PWM generator, and the IRF840 power MOSFETS transistors.
Transformer: The transformer is a high-frequency Chopper Trafo, and it performs the isolation and high-frequency transformation of the signal generated by the PWM set and switching transistors.
Fast Rectification: Formed by diode D3, this is a fast and double diode, since the oscillated frequency in the circuit is quite high.
Output filter: Composed of inductor L2 and capacitor C9.

Caution

This circuit works directly connected to the electrical network, this is extremely dangerous, any carelessness, or wrong connections, design error, or any other occasion, can lead to irreversible damage.

The PWM Circuit

The power supply for the IR2153 IC comes through a 27K 5W power-limiting resistor together with the C5 capacitor. In the internal package of this IC, there is already a 15.6V Zener diode, which stabilizes this voltage, but the current is low.

So, be careful not to put the resistor R3 with a smaller resistance, as it would increase the current at the input of the IC, and the Zener could break and consequently burn the IC.

An improved solution would be to put a 15V Zener diode to ensure voltage stabilization and IC protection, which you can be doing if you wish.

If you are using the IR2153D, there is no need to use the D2 diode which is the FR107 or BA159, as this IC already has this diode internally, if it is the IR2153 “without the letter D”, leave it as it is in the schematic, “ with diode D2”.

The complete schematic diagram is displayed just below in Figure 2, both the diagram and the materials are available for download at the link below.

Figure-2-Schematic-Diagram-SMPS-13.8V-10A-power-supply

The Transformer

The TR1 transformer was taken from a scrap ATX power supply, the model is the IE-35A, but you can be using practically any model of ATX power supply Trafo.

There is no need to rewind the transformer, just pay attention to the Pinout that we will use for the Trafo, as shown in Figure 3 below.

Fig.3-ATX-power-supply-Trafo-wire-connection-diagram

The Trafo model used was the EI-35A, but we can also use any other AT or ATX power supply that has the same standards, such as models EI-33, ER35, TM3341101QC, ERL35, EI28, etc., as shown in Figure 4 below.

Fig.4-ATX-power -supply-transformer-model-EI-35A

The L1 inductor is the same used in the ATX power supply, we removed it and didn't make any changes, and the L2 inductor, from the output EMI filter.

You can also use the AT/ATX power supply scrap, but if you want to wind your own filter, you can wind it on a Ferrite Toroidal core.

The winding must be carried out using a Toroidal core winding, with the coil using 0.6 mm super-enamelled copper wire with 25 turns.

Component List

Semiconductors
CI1 ......... Integrated Circuit IR2153D, or IR2153 (See Text)
Q1, Q2 ... IRF840 MOSFET transistors
D1 .......... KBU606 Diode Bridge (or Equivalent)
D2 .......... FR107 or BA159 Fast Diode (or Equivalent)
D3 .......... MBR3045PT Diodes Fast (or Equivalent)
Resistors
R1, R2 .... 150KΩ resistor - (brown, green, yellow, gold)
R3 .......... 27KΩ 5W resistor – (red, violet, orange, gold)
R4 ...........8K2Ω resistor – (gray, red, red, gold)
R5, R6 ... 10Ω resistor – (brown, black, black, gold)
RV1 ....... 47kΩ trimpot
NTC1..... 5Ω thermistor
Capacitors
C1, C2 ... 470nF - 400V Polyester Capacitor
C3, C4 ... 330uF - 200V Electrolytic capacitor
C5, C7 ... 100uF - 25V Electrolytic capacitor
C6 .......... 680pF Polyester Capacitor
C8 .......... 2.2uF - 400V Polyester Capacitor
C9 .......... 2200uF - 25V Electrolytic capacitor
Miscellaneous
L1, L2 .... Inductor *see text
TR1 ....... Transformer *see text
F1 .......... 5A Solderable fuse
Other...... Wire, Solder, Plate, Etc.

Printed Circuit Board

We provide the PCB - Printed Circuit Board, in GERBER, PDF and PNG files. These files are available for free download, on the MEGA server, in a direct link, without any bypass.

All to make it easier for you to do a more optimized assembly, either at home, or with a company that prints the board. You can download the files in the Download option below.

Files to download, Direct Link:

Click on the link beside: GERBER, PDF and PNG files

You can see the official post by clicking here! fvml.com.br

If you have any questions, suggestions or corrections, please leave them in the comments, and we will answer them soon.

Subscribe to our blog!!! Click Here - elcircuits.com!!!

My Best Regards!!!

5A, 1.22V to 26V, 500kHz Step-Down Converter Using RT8289 IC with PCB

Electronic Circuits Circuits to Assemble , Electronic Circuits

Fig. 1 - 5A, 1.22V to 26V, 500kHz Step-Down Converter Using RT8289 IC with PCB

This is a DC-DC 5A, 1.22V to 26V, 500kHz Step-Down Converter Using RT8289 IC, it works with a Step-Down conversion system.

This powerful chip manages to work with very few external components and provides a preset voltage between 1.22V to 26V, with 5 Amps of output current.

General IC Description

The RT8289 is a step-down regulator with an internal Power MOSFET. It achieves 5A of continuous output current over a wide input supply range with excellent load and line regulation.

Current mode operation provides fast transient response and eases loop stabilization. The RT8289 provides protections such as cycle-by-cycle current limiting and thermal shutdown.

In shutdown mode, the regulator draws 25A of supply current. The RT8289 requires a minimum number of external components, to provide a compact solution. The RT8289 is available in a SOP-8 (Exposed Pad) package.

Features

High Output Current up to 5A
Internal Soft-Start
100mΩ Internal Power MOSFET Switch
Internal Compensation Minimizes External Parts Count
High Efficiency up to 90%
25μA Shutdown Current
Fixed 500kHz Frequency
Thermal Shutdown Protection
Cycle-by-Cycle Over Current Protection
Wide 5.5V to 32V Operating Input Range
Adjustable Output Voltage from 1.222V to 26V
Available in an SOP-8 (Exposed Pad) Package
RoHS Compliant and Halogen Free

Output Voltage Setting

To define the output voltage, we use a voltage divider formed by 2 resistors, R1 and R2, this allows the FB pin of the integrated circuit to detect changes in the output voltage, and recalibrate the circuit keeping it stabilized.

To set this output voltage, we can calculate the external resistive divider, according to the equation formulated below:

VOUT = VREF *(1 + (R1/R2))

Where VREF is the reference voltage (type 1.222V).
Where R1 = 10kΩ.

We exemplify in our circuit, the voltage divider is formed by R1 and R2.

General Formula:

VOUT = VREF *(1 + R1/R2)
Where VREF is the reference voltage (type 1.222V).
Where R1 = 10kΩ.

For a 3.3V output, our formula would look like:

Vout = 1,222 * (1+ (10/5.8))
Vout = 3.328V

For a 5V output, our formula would look like:

Vout = 1,222 * (1+ (10/3.16))
Vout = 5,089V

For a 9V output, our formula would look like:

Vout = 1,222 * (1+ (10/1.57))
Vout = 9,005V

For a 12V output, our formula would look like:

Vout = 1,222 * (1+ (10/1.13))
Vout = 12,036V

For a 26V output, our formula would look like:

Vout = 1,222 * (1+ (10/0.493))
Vout = 26,009V

We may be using a trimpot instead of R2, this allows you to vary the output voltage through the Trimpot.

The Circuit Schematic

In Figure 2, below, we can see the schematic diagram of the Low Noise and High Frequency 5A DC-DC Step-Down Converter.

All circuit components are SMD, except the terminal blocks, “optional”, you can solder directly to the board. This type of SMD circuit is great to be implemented in miniaturized circuits.

It is preferable to use tantalum capacitors, but if you cannot find them, electrolytic capacitors can be used, but for more sensitive circuits, we recommend using tantalum.

The DC-DC converter supports input from 5.5V to 32V, and at the output it maintains the preset voltage completely stabilized.

Fig. 2 - Schematic 5A, 1.22V to 26V, 500kHz Step-Down Converter Using RT8289 IC

Printed Circuit Board

In Figure 3, we provide the PCB - Printed Circuit Board, in GERBER, PDF and PNG files. These files are available for free download, on the MEGA server, in a direct link, without any bypass.

All to make it easier for you to do a more optimized assembly, either at home, or with a company that prints the board. You can download the files in the Download option below.

The PCB tracks are doubled, the main ones have their tracks on the bottom and top of the PCB as the current is 5 amps.

Fig. 3 - PCB 5A, 1.22V to 26V, 500kHz Step-Down Converter Using RT8289 IC

Files to download, Direct Link:

Click on the link beside: GERBER, PDF and PNG files

If you have any questions, suggestions or corrections, please leave them in the comments, and we will answer them soon.

Subscribe to our blog!!! Click Here - elcircuits.com!!!

My Best Regards!!!

Electronic Resistive Load - 50A Power Supply Test with PCB

Electronic Circuits Circuits to Assemble , Electronic Circuits

Fig. 1 - Electronic Resistive Load - 50A Power Supply Test with PCB

You know that moment when you have a power supply to fix, you do the service and the supply works, but you don't know if it will support a large load?

I came across a problem like this, and I decided to make my own resistive electronic load, and share it with our subscribers, and for you who visit us, welcome!

The circuit

The circuit is quite simple, with few components and easy to assemble, based on two power transistors Mosfet N-channel, IRL44N connected in parallel.

The circuit is capable of withstanding an initial load “for low voltage sources 4V” of 40A, and for voltage above 5V, the current is 50A, supporting voltages up to 45V.

This voltage is received and transformed into heat, and the consumption current is controlled by means of a potentiometer.

Transistor Description

Fifth Generation HEXFETs from International Rectifier utilize advanced processing techniques to achieve the lowest possible on-resistance per silicon area.

This benefit, combined with the fast switching speed and ruggedized device design that HEXFET Power MOSFETs are well known for, provides the designer with an extremely efficient device for use in a wide variety of applications.

The TO-220 package is universally preferred for all commercial-industrial applications at power dissipation levels to approximately 50 watts.

The low thermal resistance and low package cost of the TO-220 contribute to its wide acceptance throughout the industry.

How it works

When turning on the electronic resistive load, a current passes through the Drain and Source taps, and this current flow is controlled by the Mosfet Gate.

For this control to happen properly, a stabilized voltage is needed at that point, which is done through the resistor R1, current limiting, in series with the zener diode, which stabilizes the voltage at the Gate.

This stabilized voltage ensures that the current not be variable when the input voltage undergoes some variation.

This stabilized voltage point is controlled by the potentiometer P1, which adjusts the voltage at the Gate of the Mosfet according to the required current.

It is worth remembering that the transistor used is a logic-type IRL44N Mosfet, not the well-known IRF44N.

They differ in relation to the gate voltage, as the logic-type Mosfet triggers the Gate with low Vgs voltages from 4V, and the IRF44N does not work with such low voltages, the minimum Vgs is 7V.

The Circuit

The schematic diagram of the Electronic Resistive Load - Power Supply Test!, is shown in Figure 2 below, it is a simple circuit to assemble, there are few external components to solder, however it is a circuit of great quality and stability.

Fig. 2 - Electronic Resistive Load - 50A Power Supply Test

Component List

Semiconductors

Q1, Q2 .... IRL44N Mosfet Transistor
D1 ........... 1N4731 1W Zener Diode

Resistors

R1 ........ 1.8KΩ resistor (brown, grey, red, gold)
R2 ........ 0.22Ω resistor (red, red, silver, gold)
POT1 ... 220KΩ Potentiometer

Miscellaneous

P1 .... Screw Terminal Type 5mm 2-Pin Connector
Others .... PCB, Heat Sink, tin, wires, etc.

The PCB - Files to Download

In Figure 3, we provide the PCB - Printed Circuit Board, in GERBER, PDF and PNG files. These files are available for free download, on the MEGA server, in a direct link, without any bypass.

All to make it easier for you to do a more optimized assembly, either at home, or with a company that prints the board. You can download the files in the Download option below.

Fig. 3 - PCB Electronic Resistive Load - 50A Power Supply Test

Files to download, Direct Link:

Click on the link beside: GERBER, PDF and PNG files

If you have any questions, suggestions or corrections, please leave them in the comments, and we will answer them soon.

Subscribe to our blog! Click Here - elcircuits.com!

My Best Regards!

4A Low-Noise High-Frequency Step-Up DC-DC Converter using MAX1709 with PCB

Electronic Circuits Circuits to Assemble , Electronic Circuits

Fig. 1 - 4A Low-Noise High-Frequency Step-Up DC-DC Converter using MAX1709 with PCB

This is a DC-DC converter circuit that uses a MAX1709 series Integrated Circuit as the main component, it works with a Step-Up conversion system.

This powerful microcircuit is able to work with very few external components and deliver a fixed 3.3V or 5V or adjustable 2.5V to 5.5V voltage, with 4 Amperes of output current.

Integrated Circuit General Description

The MAX1709 sets a new standard of space savings for high-power, step-up DC-DC conversion. It delivers up to 20W at a fixed (3.3V or 5V) or adjustable (2.5V to5.5V) output, using an on-chip power MOSFET from a +0.7V to +5V supply.

Fixed-frequency PWM operation ensures that the switching noise spectrum is constrained to the 600kHz fundamental and its harmonics, allowing easy post filtering for noise reduction.

External clock synchronization capability allows for even tighter noise spectrum control. Quiescent power consumption is less than 1mW to extend operating time in battery-powered systems.

Two control inputs (ONA, ONB) allow simple push-on, push-off control through a single momentary push button switch, as well as conventional on/off logic control.

The MAX1709 also features programmable soft-start and current limit for design flexibility and optimum performance with batteries.

The maximum RMS switch cur-rent rating is 10A. For a device with a lower current rating, smaller size, and lower cost, refer to the MAX1708 datasheet.

The Circuit Schematic

In Figure 2, below, we can see the schematic diagram of 4A Low-Noise High-Frequency Step-Up DC-DC Converter using MAX1709.

The circuit is simple to assemble, there are few external components, and there is no need for adjustment, once assembled, it is ready to work, if everything is correct, of course!

The PCB tracks are bent, the main ones have their tracks at the bottom and at the top of the PCB, because the current is 4 amperes.

The capacitors are tantalum, however if you can't find them, electrolytic capacitors can be used, however for more sensitive circuits, the performance may not be as expected, but in most circuits they work very well.

The DC-DC converter supports input from 0.7V up to 5V, and at the output it maintains the stabilized voltage of 5V, however to get the promised 4 Amps, it is necessary to have at least 3.3V at the input.

Fig. 2 - Schematic Circuit 4A Low-Noise High-Frequency Step-Up DC-DC Converter using MAX1709

Components List

Semiconductors

U1 ...... MAX1709 SMD Integrated Circuit
D1 ..... B520C SMD Schottky Diode 5A

Resistor

R1 ..... 312KΩ SMD resistor (orange, brown, red, orange, gold)
R2 ..... 2Ω SMD resistor (red, black, black, gold)

Capacitor

C1, C2, C6, C7 ... 150uF SMD Tantalum Capacitor
C3 ....................... 10nF SMD Ceramic Capacitor
C4 ....................... 220nF SMD Ceramic Capacitor
C5 ....................... 100nF SMD Ceramic Capacitor

Miscellaneous

L1 .......... 1uH 5A SMD Inductor
P1, P2 .... 2-pin PCB soldering terminal blocks (Optional)
Others .... Printed Circuit Board, wires, etc.

Printed Circuit Board

All to make it easier for you to do a more optimized assembly, either at home, or with a company that prints the board. You can download the files in the Download option below.

Fig. 3 - PCB - 4A Low-Noise High-Frequency Step-Up DC-DC Converter Using MAX1709

Files to download, Direct Link:

Click on the link beside: GERBER, PDF and PNG files

If you have any questions, suggestions or corrections, please leave them in the comments and we will answer them soon.

Subscribe to our blog!!! Click Here - elcircuits.com!!!

My Best Regards!!!

Adjustable Switching Power Supply 5.1 to 40V, 2.5 Amp using L4960 + PCB

Electronic Circuits Circuits to Assemble , Electronic Circuits

Fig. 1 - Adjustable Switching Power Supply 5.1 to 40V, 2.5 Amp using L4960

In this article, we present an adjustable power supply with a stabilized output that varies from 5.1 to 40V, with a current of 2.5 amps.

This one can also have its stabilized voltage fixed, everything will depend on the type of project you are going to use.

The adjustable power supply is based on IC L4960 which is a monolithic power switching regulator IC, delivering 2.5A at a voltage variable from 5V to 40V in step down configuration.

Features of the device include current limiting, soft start, thermal protection and 0 to 100% duty cycle for continuous operation mode.

The complete schematic diagram of the power supply is shown below in Figure 2, it is a simple but complete power supply.

Fig. 2 - Schematic Adjustable Switching Power Supply 5.1 to 40V, 2.5 Amp using L4960

CIRCUIT OPERATION

The L4960 is a monolithic step down switching regulator providing output voltages from 5.1V to 40V and delivering 2.5A.

The regulation loop consists of a sawtooth oscillator, error amplifier, comparator and the output stage. An error signal is produced by comparing the output voltage with a precise 5.1V on-chip reference (zener zap trimmed to ± 2%).

This error signal is then compared with the sawtooth signal to generate the fixed frequency pulse width modulated pulses which drive the output stage.

The gain and frequency stability of the loop can be adjusted by an external RC network connected to pin 3.

Closing the loop directly gives an output voltage of 5.1V. Higher voltages are obtained by inserting a voltage divider.

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Output overcurrent at switch on are prevented by the soft start function. The error amplifier output is initially clamped by the external capacitor Css and allowed to rise, linearly, as this capacitor is charged by a constant current source. Output overload protection is provided in the form of a current limiter.

The load current is sensed by an internal metal resistor connected to a comparator. When the load current exceeds a preset threshold this comparator sets a flip flop which disables the output stage and discharges the soft start capacitor.

A second comparator resets the flip flop when the voltage across the soft start capacitor has fallen to 0.4V.

The output stage is thus re-enabled and the output voltage rises under control of the soft start network.

If the overload condition is still present the limiter will trigger again when the threshold current is reached. The average short circuit current is limited to a safe value by the dead time introduced by the soft start network.

The thermal overload circuit disables circuit operation when the junction temperature reaches about 150°C and has hysteresis to prevent unstable conditions.

Efficient operation at switching frequencies up to 150KHz allows a reduction in the size and cost of external filter components.

The L4960 is mounted in a plastic Heptawatt power pack, and the pinouts are shown in Figure 3 below.

Fig. 3 - L4960 IC Heptawatt Pinout

Download

We provide the files with the PCB, the schematic, the PDF, GERBER and JPG, PNG and provide a direct link for free download and a direct link, "MEGA".

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Fig. 4 - Adjustable Switching Power Supply 5.1 to 40V, 2.5 Amp using L4960

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How Switched Mode Power Supply Works - SMPS - ATX

Electronic Circuits Learning , power supply

ATX Switched-Mode Power Supplies have some interesting features when compared to standard Switched Mode Power Supply (SMPS).

In the ATX power supply, there are different output voltages: + 12V, + 5V, + 3.3V, -12V, -5V and 5VSB. There are some variations on these types of Power Supply, but in the general context, the pattern is this.

The way SMPS work is pretty much the same.

They control the output voltage by opening and closing the switching circuit so as to maintain the opening and closing time of this circuit, that is, the width of the pulses and their frequencies, to obtain the desired voltage.

There are separate processes for everything to work smoothly.

So let's see the modular diagram to unravel the steps of these processes so that we can step by step understanding.

This is the block in modules divided by steps, to improve our understanding.

There are 10 basic steps to running an ATX power supply, there are other underlying modules that are intrinsic in the steps, but, we'll not go as deep as it would be extremely great this Blogger, for those who want to watch the explanatory video with details in Portuguese. On the original post channel from YouTube.

Original Portuguese Version: Click Here

Switched Power Supply SMPS 13.8V 10A using IR2153 IC and IRF840, with PCB
Adjustable Power Supply 1.2V to 37V, 6A, Short Circuit Protection with LM317 and TIP36 + PCB
Symmetrical Adjustable Power Supply 1.25V to 47V 10 Amps with Short Circuit Protection + PCB
Adjustable Power Supply 1.2 to 37V High Current 20A with LM317 and TIP35C + PCB
Adjustable Power Supply 1.25v to 57V, 6 Amps with TIP36C + LM317HV + PCB
Adjustable Power Supply 1.25v to 33V, 3 Amps with LM350 + PCB
Stabilized Power Supply 13.8V High Current 10 Amps with PCB

So let's understand these steps:

Step 1 - Transient Filter

Is through that stage that the voltage coming from your network, whether 110 or 220V AC should enter.

Transient Filter

This voltage goes through basic protection, the fuse, that if some step ahead short, the fuse opens, avoiding to burst everything ahead, and in the same line, we have the NTC (Negative Temperature Coefficient), It's a surge current limiter, in series with the electric circuit,

In it the value of ohmic resistance decreases as its temperature rises, its initial resistance is approximately 15 Ohms, which we can understand by the Ohms' law, the advantages one has in using it in series after the power supply switches it on lowers its resistance to approximately 0.5 Ohms.

EMI filters also exist, these are used to avoid high-frequency noise and a huge amount of harmonics generated by the switches that can propagate through the electrical network and cause interference in nearby electronic equipment.

Step 2 - Primary Rectification

Primary Rectification

In this stage we find the rectifier bridge or an arrangement formed by four common diodes, which has the function of rectifying a full-wave voltage, that is, rectifying an alternating electric current (AC), transforming it into a continuous electric current ( DC).

Step 3 - Filtration

Filtration

After rectification, the DC signal, Ripples (which are small variations, the capacitors are responsible for the filtering and stabilization IE, a decrease of these Ripples, in the rectified voltage, this voltage rises to something around 300V, which are used in the power switches, this part is fundamental to the correct stabilization of the source especially if its source is of high power.

Step 4 - Power Switches

Power Switches

These switches can be Bipolar Power Transistors such as MOSFETs, or any other type, but they differ from ordinary transistors, by the type of operation in which these transistors work, these switching transistors dissipate less power than a common working transistor in a linear source because they work as a switch on / off at high speeds, depending on the design of the source, they suffer variations that are usually between 20Khz to 100kHz, they are directly responsible for the output voltage, and stability of that voltage, through of the commands received by the Control Circuit.

Step 5 - Output Transformer

Output Transformer

The transformer is a high-frequency CHOPPER TRANSFORMER, and they also work with alternating voltage, when passing through the switches the voltage will be a square wave AC type PWM, but with high frequency, not with the same frequency of 60Hz of the input voltage.

The switches work on two different levels, High and Low, when it is HIGH, the voltage goes through it normally, causing a constant voltage level in the input of the coil of the transformer, the action of these transistors, goes from HIGH to LOW very quickly.

This will induce the winding to have the necessary voltages according to the winding and frequency placed on these switches.

Step 6 - Fast Rectifier

Fast Rectifier

With the voltage generated by high-frequency switches, a diode is needed to meet this demand, so we have the high-speed diodes called SCHOTTKY DIODES or fast recovery diodes since ordinary diodes would not be able to work with high-frequency voltages.

Step 7 - Output Filters

Output Filters

The inductor - This has the function of eliminating the high-frequency harmonics so that they do not travel to the equipment that will be fed, imagine if these harmonics pass to a micro-controller for example, could cause undue loads and errors of reading in the control processes.

And the Capacitors - They are the ones that filter and stabilize the voltage at the output, avoiding ripples and instabilities at the output.

Step 8 - Driver Transformer

Driver Transformer

The driver transformer in this case is nothing less than the one responsible for traffic the information coming from the Integrated Circuit Controller, and pass these commands to the switches, so as to bring insulation or electrical decoupling between primary and secondary, in this topology there is a pair of transistors that also switch the Transformer Drive to receive these PWM pulses from the driver IC, passing this information to the power step we already saw in Step 4.

Step 9 - PWM control

PWM control

The brain of a switched source is its PWM controller, they are dedicated integrated circuits, to perform that work, but they do not work alone, there are also current sensors, which also vary from source to source, but it is very likely that you will find in its source the TL341 IC, it has the aspect of a transistor, but, it is not a transistor, it is very popular for its cost-benefit.

This circuit is connected to the output of the power supply, receives Feedback, and directs the voltage information to the IC that controls the oscillator that generates a rectangular signal whose pulse width is controlled and sent to the Transformer Drive that sends these commands to the step of power.

If the power at the output to raise the voltage tends to drop, the circuit activates the instantaneous correction in the pulse width of the switching transistors and the voltage keeps stabilized.

Step 10 – Primary Power Supply VSB

Primary Power Supply VSB

VSB stands for Voltage Standby, which is technically a power supply that keeps its output active, whenever the source power cord is connected to the mains, its capacity is approximately 2 Amps, and this depends on the total power of the source, this active voltage line is to keep the circuit active and is necessary for when the power on button is activated through PSON, which is the start of the power supply, then the oscillator will activate the power line also powers the motherboard hardware to activate peripherals via software, keyboard, network, and so on.

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Friday, April 14, 2023

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Technical Specifications

Design

Caution!

Features

TNY268 - Pinout and Description

We leave below the description of each pin of the TNY268 Integrated Circuit to facilitate our understanding.

The Switched Power Supply Circuit

Regulate The Output Voltage

The output voltage is adjusted through two parameters in the circuit:

The Zener Diode

For example:

The Transformer

Primary coil winding

Secondary coil winding

The calculation for an output voltage of 5V can be achieved using the formula below:

The calculation for an output voltage of 9V:

The calculation for an output voltage of 12V:

The calculation for an output voltage of 24V:

For 24V output, we have 37 turns to wind in the secondary.

Components list

Semiconductor

Resistor

Capacitors

Several

Printed Circuit Board - Download

Conclusion

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Monday, January 30, 2023

Switched Power Supply SMPS 13.8V 10A using IR2153 IC and IRF840, with PCB

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The Circuit

The circuit basically consists of 8 main steps:

Caution

The PWM Circuit

The Transformer

Component List

Printed Circuit Board

Files to download, Direct Link:

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Wednesday, June 22, 2022

General IC Description

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Features

Output Voltage Setting

General Formula:

For a 3.3V output, our formula would look like:

For a 5V output, our formula would look like:

For a 9V output, our formula would look like:

For a 12V output, our formula would look like:

For a 26V output, our formula would look like:

The Circuit Schematic

Printed Circuit Board

Fig. 3 - PCB 5A, 1.22V to 26V, 500kHz Step-Down Converter Using RT8289 IC

Files to download, Direct Link:

Wednesday, May 18, 2022

The circuit

Transistor Description

How it works

The Circuit

Component List

The PCB - Files to Download

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Saturday, February 26, 2022

Integrated Circuit General Description

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The Circuit Schematic

Components List

Printed Circuit Board

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Monday, December 6, 2021

CIRCUIT OPERATION

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Monday, September 14, 2020

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So let's understand these steps:

Step 2 - Primary Rectification

Step 3 - Filtration