HOW TO MAKE SMPS FROM GACUN

Before heading straight to the main material, we should first know what is Gacun. If you are an electronics technician who often deals with PSU (Power Supply Unit) TV, then the term Gacun is not unfamiliar. Because the Switching Module of Gacun is often applied if the problem of TV PSU is difficult to overcome.

Kit / Module Power Supply Gacun is a very innovative breakthrough. Can be applied to any regulator including TV, as long as the transformer transformer is still good. With this kit the technicians are very helpful to replace the original regulator circuit.

In this article we do not discuss more deeply about how to apply / install Gacun for TV regulator, but we will make power supply amplifier by using this Gacun module.

Apparently Gacun is very flexible, in addition to the iron transformer prices soar, until finally Gacun module can be a solution in making SMPS cheap. Supporting components can also be obtained from used goods such as TV mainboard and used computer PSU. Function of Gacun in this application as driver of ferrite core transformer / switching transformer.

The required materials are as follows:

1. Switching regulator module / Gacun

2. Transformer: For the transformer we can roll it yourself or the transformer from the former switching regulator that has been damaged and we use the transformer, the easiest looking former TV regulator and used computer PSU

3. Supporting components include: transistor, capasitor, optocoupler, zener diode, resistors etc.

4. Measuring tool: Multi Tester and LCR meter (if any).

How to make coils and count the number of coils.

Often we make coils that mostly do not understand how many coils should be wrapped and what their inductance values are after the coil and what is the ideal, it is related to the ferrite material, the airgap and the physical size of the ferrite.

The better the permeability of ferrite (Bmax) the less the number of coils, the greater the airgap the more the coil and the greater the physical size of the ferrite the less the number of coils, so with the reasoning obtained conclusion, if one or the three elements are different then the number of coils is of course different.

Well how many coils that fit and efficient? Based on repeated tests the ideal inductance value is 500 μH if we have an LCR meter.

Data wire coil :

NP / Primary Coil = 45 twists (not self-made standard)

NS / Secondary Coil = 2 volts / coil (depending on need)

The size of the diameter of the wire determines the amount of power / ampere obtained.

How to wrap wire switching transformer as in the picture, do not upside this one of the keys to successful SMPS Gacun.

Fet Gacun can be paralleled in order to handle large power. However, it is recommended if we have successfully used the standard Gacun.

WORK PRINCIPLE SMPS SIMPLE CIRCUIT

For this first post we try to learn to know what is SMPS. The easiest term in describing SMPS (Switch Mode Power Supply) is a tool designed for alternative Power Supply. So far we often see the iron transformator as the main component of a conventional power supply.

Understanding SMPS

For understanding SMPS has 2 sense that is:

1. Power Supply is a device used to produce or provide a suitable and stable power source in a particular equipment. And usually the available voltage is alternating voltage 220v or can be called with AC, but an electronics equipment requires DC voltage or direction.

2. Switching Regulator which is an electronic circuit used to stabilize the outgoing voltage, such as the outgoing voltage is not optimal, the load current is less than optimal and other

How SMPS Works :

~ Submission - change AC input voltage to DC output voltage.

~ Converter - converts DC voltage to output voltage according to need.

~ Filtering - removes the pulse at the output voltage.

~ Regulation - makes the output voltage stable to the input voltage changes and load changes.

~ Isolation - Isolate the secondary part of the primary part, with the aim that the chassis of the secondary part if held does not arise the danger of electric shock.

~ Protection - able to protect equipment from over-voltage output and protect power supply from damage in case of error.

The basic parts of SMPS work are as follows:

~ Parts Rectifier. Here the input voltage of 220V AC power is rectified to DC voltage using a diode bridge and 3 large elco filter that is an elco 480V680UF and 2 elco 250V2200UF.

~ Part of enumerator or power-switching. The DC input voltage is enumerated using "on-off power switch" to produce high-frequency pulses of dc pulses. SMPS Inverter welding machines generally work at frequencies from 50Hz to 60Hz. As a power switch can use IC K2611, IRFZ24N and IRF9Z24N.

~ SMPS Controller driver as PWM (Pulse Wave Modulation) pulse generator. As the drive signal for the enumerator used PC 817 IC containing oscillator circuit and PWM as a generator of PWM pulses. There is a SMPS circuit that does not use the SMPS controller driver, in which case a power switching transistor is made to work by "oscillating itself".

~ Switching transformer. The dc voltage that has been chopped has characteristics such as ac voltage so it can be passed by a transformer or inductor to be raised or lowered voltage.

~ The rectification and filtering of the output voltage. The output voltage of the transformer is still a high frequency pulse and then converted to DC voltage using rectifier diode and elco filter.

~ Loop feedback to make the output voltage stable. The feedback loop circuit from the output voltage B + to the primary is used to control the PWM.

~ Comparator circuit as "error detector". A comparator circuit on the secondary part is used to detect if there is a change in the output voltage B +. The comparator works by comparing the output voltage B + with a "reference" voltage (usually a zener diode voltage of 6.8v). The comparator output is a current which is then fed back to the primary through a photo coupler. The coupling using a photocouler aims to isolate the ground of the primary part of the electric shock when held (HOT chassis) with the secondary ground (COLD chasis).

Dimensions and weights.

The ancient powerhouses, especially the most powerful ones, always have large dimensions and heavy weights (capacity determines dimensions and weights), the working frequency is the same as the 50-60 Hz power grid. Whereas SMPS uses much higher working frequency at 50 kHz - 500 kHz. The higher the frequency means the more efficient it works, so it requires a power transformer that is smaller, lighter weight. Thus the size of equipment that uses SMPS as its resources must be more compact size.

Efficiency, Voltage and Output Flow.

The output voltage of the conventional supply depends on the tap on the power transformer. For unregulated types, the output voltage varies depending on the load current. While that is being circulated, the process causes the power dissipation of the transistor (in the form of heat) to decrease the usability, as well as the core conductor losses and the iron core kern is very large, which ultimately all that can produce efficiency only 30-40% only.

At SMPS the voltage is easily set at any voltage and at any current according to the installed capacity without much effect on the dimensions and weights. In SMPS enforcement techniques, regulation is obtained only by adjusting the pulse width, and since the transistor is working completely or completely alive, the heat (and loss of power) is minimal. The disadvantage caused by the capacitor depends only on ESR (equivalent series resistance), so its value is relatively small. Loss of the ferrite core, core conductor and drop-voltage resistor diode. All the so-called contributors are major losers, but with all the losses it can produce a typical efficiency of 60-80%. By improving circuit design, losses can still be minimized, until 95% efficiency is not impossible to achieve.