Workings of STR IC Regulator Power Supply

The meaning STR in this article for example is a Sanken regulator series and Fairchild series STR-F/G/W KA05Q Is an ic Quasy Resonant Flyback (QRF) Swiching Regulator comprising (a) control IC and (b) power MOSFETs that are packed into a single unit. The regulator is designed so that only requires a few external components.

How it works :

A. UVLO (under voltage lock out)

Regulators will start working when the voltage Vcc start-up on pin-4 reaches 16V. Once the power supply voltage Vcc further work will be reimbursed through a switching transformer supplied from a diode rectifier. At the time the circuit was working when the voltage Vcc is less than 15V, the regulator controls will still work. regulator will stop working (protectionism) if the supply voltage Vcc drops to less than 11V.

  

2. Feedback control (pin-1)

PWM regulators work using the system, wherein the output voltage B + to stable controlled by the feedback circuit of the output voltage B + >>> >>> photo-coupler pin-1. A capacitor mounted on the pin-1 is used to prevent noise disturbance if anyone does not interfere with the working system.

  

3. Soft start (pin-5)

When the power is turned on first, then the circuit has not been working behind the Uman because there is no output voltage B +. This causes a heavy current on the MOSFET start. To prevent this, the regulator is equipped with soft start circuit internally and an external filter kapasitr.

If the power supply is used to monitor for example, the frequency of the regulator needs to be synchronized. External synchronization signal can be input through pin-5s

  

4. Protectors

Regulators are equipped with all sorts protector.

• Over-current protector (OCP) or Over Load protector (OLP). For example, if there is damage to flyback or def yoke, it will cause the load voltage B + over. If there is such a case the regulator will die protectionism so that IC is not damaged. For over current sensor is a resistor with a small value that is placed on pin-2 to the ground.
• Short protector. If the output voltage B + short, the regulator turns off protectionism.
• Over-voltage protectors (OVP). Regulators are not equipped with a surge protector so if the feedback path disconnected can cause the output voltage of the transformer switching regulator power up or damaged .. With OVP protectionist regulator will die if the voltage supply Vcc pin-4 rise above 22.5v.
• Thermal protector. Regulators will stop working if the temperature reaches 140 degrees Celsius.

6. Auto start.

Regulators will start automatically if the auto turns itself (protectionism) after OVP or OCP

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Simple 7805 Voltage Regulator Circuit

A voltage regulator is used to produce a constant linear output voltage. It’s generally used with AC to DC power supply. And also it can be used as well as a DC to DC voltage converter . To regulating low voltage, most used device is one single IC. 7805, 7812, 7905 etc. 78xx series are design for positive and 79xx series are for Negative voltage regulator.

7805 is a three terminal +5v voltage regulator IC from 78XX chips family. See 7805 pinout below. LM78XX series are from National Semiconductor. They are linear positive voltage regulator IC; used to produce a fixed linear stable output voltage.  National Semiconductor has also negative voltage regulator chips family, they indicate with LM 79XX. 78xx is used more than 79xx because negative voltage has a few usability purposes as we see.
I was previously posted a 5v regulated power supply circuit using 7805 IC, that circuit and this 7805 voltage regulator circuit is almost the same.

Its output voltage is +5V DC that we need. You can supply any voltage in input; the output voltage will be always regulated +5V. But my recommendation is, don’t supply more than 18V or less than 8V in input. There used two capacitors in this voltage regulator circuit, they aren’t mandatory to use. But it will be best if you use them. They helped to produce a smooth regulated voltage at output. Use electrolyte capacitor instead of ceramic capacitor.

One limitation of 7805 I have found that is its output current 1A maximum. Otherwise it is a good voltage regulator if you are happy with 1A. But if   you need over 400mA current in output then you should use a Heat Sink with IC LM7805. Otherwise it may fall damage for overheating. 

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10V Switching Regulator Using LM5007

10V Switching Regulator Using LM5007 Circuit Diagram

The circuit diagram shown here is of a 10V switching regulator based on the LM5007 from National Semiconductors. The LM5007 is an integrated step down switching regulator which has all necessary systems required for making a cost effective and reliable switching regulator circuit. The IC is available in MSOP-8, LLp-8 packages and has a lot of built in features like thermal shut down, under voltage lock out, duty cycle limiting, current limiting etc.

The output voltage of this regulator can be adjusted using the resistor R3 and R4. For the given values of R3 and R4 in the circuit diagram, the output voltage will be 10V. The equation governing the output voltage is Vout = 2.5 x (R3+R4)/R4. Resistor R1 sets the switch on time and C4 is the boost boot strap capacitor. Resistor R2 determines the variation of OFF time and C3 is a decoupling capacitor.

Notes.

* The supply voltage can be anything between 12 to 72V DC.
* Output voltage can be adjusted using R3 and R4.
* C1 and C5 are polyester capacitors.
* C1 and C2 must be rated at least 100V.
* R5 and C5 forms a filter network.
* The output current limit of LM5007 is 700mA.

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Troubleshooting STR IC Regulator Power Supply

A. Unable to start.

Can be caused by:

• No start-up voltage supply Vcc or a voltage less than 16V
• Electrolityc Capacitors supply voltage Vcc filter dry.

  

2. Led indicator blinking

If the supply voltage Vcc examined rocking. This is because the regulator of life and death because OVLO work., Die-protectionist regulators and auto start life over and over. If it is turned off  Electrolityc Capacitors  usually still keep the rest of the cargo.

Can be caused by:

• Electrolityc Capacitors supply voltage Vcc filter on a pin-4 dry. Replace with a value equal to or slightly larger. - triger UVLO
• input filter capacitor on pin-1 feed dry behind the declining value - triger OLP
• Rectifier diode of the switching transformer is damaged (sometimes when examined with avo-meter looks like a still good)
• cause the supply voltage Vcc drops of the switching transformer (UVLO)
• Part damage or broken lines on the feedback circuit of the voltage regulator through B to photocoupler - triger OVP
• Electrolityc Capacitors dry filter voltage B - triger OVP
• One of the output voltage of the switching transformer secondaries there is a short (over load) - triger OLP
• Soft start capacitor value decreases - triger OLP

3. Noise arising (noise)

Can be caused by:

• Transformer windings slack.
• If there are ceramic capacitors - can sometimes cause interference noise due to its characteristic piezoelectrik like crystal resonator. Replace with film capacitors.

4. When the st-by normal stress. But when the power is on the regulator directly off protectionism no voltage on the secondary this part.  Electrolityc Capacitors  are still storing charge.

Can be caused by:

• Sensor OVP small value resistor on pin-2 to the ground so that the value of delayed triger to OLP or OCP.
• Regulator IC is damaged

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Overcurrent Trip Regulator Power Supply

Overcurrent Trip Regulator Power Supply Circuit

Available to 4QD-TEC members are rather more sophisticated power supplies: a larger supply of the same nature s this is available, with parts information and board layout. A Circuit board is also likely to be made available in time.

Also in preparation are details of a full laboratory type power supply with fully adjustable current limiting and output voltage. This can be used to make, maybe, 0-50v at 0-5 A, or other ranges as the builder may require.

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Gentle Battery Regulator

This small but very effective circuit protects a lead-acid battery (12-V solar battery or car battery) against overcharging by a solar module when the incident light is too bright or lasts too long. It does so by energizing a fan, starting at a low speed when the voltage is approximately 13.8 V and rising to full speed when the voltage exceeds 14.4 V (full-charge voltage). The threshold voltage (13.8 V) is the sum of the Zener diode voltage (12 V), the voltage across the IR diode (1.1 V), and the base-emitter voltage of the 2N3055 (0.7 V). In contrast to circuits using relays or IC amplifiers, the circuit has a gradual switching characteristic, which avoids relay chatter and the constant switching on and off near the switching point produced by a ‘hard’ switching point.

The circuit does not draw any current at all (auto power-off) below 13 V. Pay attention to the polarization of the Zener and IR diodes when building the circuit. The transistor must be fitted to a heat sink, since it becomes hot when the fan is not fully energized (at voltages just below 14 V). A galvanized bracket from a DIY shop forms an adequate heat sink. The indicated component values are for a 10-W solar module. If a higher-power module is used, a motor with higher rated power must also be used. The circuit takes advantage of the positive temperature coefficient of the lamp filament. The filament resistance is low at low voltages and increases as the voltage rises. This reduces the speed of the fan to avoid generating an annoying noise level. The lamp also provides a form of finger protection.

If you stick your finger into the fan blade, the lamp immediately takes over the majority of the power dissipation and lights brightly. This considerably reduces the torque of the fan. An ordinary 10-W or 20-W car headlight (or two 25-W headlights in parallel) can be used for the lamp. Don’t try to replace the LED by two 1N4001 diodes or the like, replace the ZPY12 by a ZPY13, or fit a series resistor for the LED. That would make the ‘on’ region too large.

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Low drop Regulator with Indicator Wiring diagram Schematic

Even today much logic is still powered from 5 volts and it then seems obvious to power the schema using a standard regulator from a rectangular 9-V battery. A disadvantage of this approach is that the capacity of a 9-V battery is rather low and the price is rather high. Even the NiMH revolution, which has resulted in considerably higher capacities of (pen-light) batteries, seems to have escaped the 9-V battery generation. It would be cheaper if 5 volts could be derived from 6 volts, for example. That would be 4 ‘normal’ cells or 5 NiMH- cells. Also the ‘old fashioned’ sealed lead- acid battery would be appropriate, or two lithium cells.

 

Low-drop Regulator with Indicator Circuit Diagram

 

Using an LP2951, such a power supply is easily realised. The LP2951 is an ever- green from National Semiconductor, which you will have encountered in numerous  Elektor Electronics designs already. This IC can deliver a maximum current of 100 mA at an input voltage of greater than 5.4 V. In addition to this particular version, there are also versions available for 3.3 and 3 V output, as well as an adjustable version.  In this design we have added a battery indicator, which also protects the battery from too deep a discharge. As soon as the IC has a problem with too low an input voltage, the ERROR output will go low and the regulator is turned off via IC2d, until a manual restart is provided with the RESET pushbutton.

 

The battery voltage is divided with a few resistors and compared with the reference voltage (1.23 V) of the regulator IC. To adapt the indicator for different voltages you only need to change the 100-k resistor. The comparator is an LP339. This is an energy-friendly version of the LM339. The LP339 consumes only 60 µA and can sink 30 mA at its output. You can also use the LM339, if you happen to have one around, but the current consumption in that case is 14 times higher (which, for that matter, is still less than 1 mA).

 

Finally, the LP2951 in the idle state, consumes about 100 µA and depend- ing on the output current to be deliv- ered, a little more. 

Source by : Streampowers

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Simple Switching Regulator Converter Wiring diagram Schematic

This is a Simple Switching Regulator Converter Circuit Diagram  . The Max650 switching regulator produces a regulated 5 V from large negative voltages, such as the -48 V found on telephone lines. The resulting power supply operates with several external components, including a transformer, and it delivers 250 mA. The device includes a 140-V 250-mA pnp transistor, short-schema protection, and all necessary control schemary.

Simple Switching Regulator Converter Circuit Diagram

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Using IFR Voltage Regulator Wiring diagram Schematic

The IFR EW a MOSFET transistor, such as transistor has higher feature high input impedance. In this schema we used an IFR as transistor voltage regulator, which is not common, but it is very good to learn about their behavior in a schema.

 Using IFR Voltage Regulator Circuit Diagram

This voltage regulator schema uses a MOSFET is
IRF4905 (Vdss =-55V, RDS (on) = 0.02ohm, Id =-74A),
but any other can be tested.

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Very Low Dropout Linear Regulator Wiring diagram Schematic

This linear post regulator provides 12 V at 3 A. It employs TL431 reference Ul which, without additional amplification, drives TMOS MTP3055A gate Ql series pass regulator. Bias voltage is applied through Rl to Q1`s gate, which is protected against overvoltage by diode CRl. 

Frequency compensation for closed-loop stability is provided by Cl. Key performance features are: Dropout voltage: 0.6 V Load regulation: lOmV Line regulation: ± 5 m V Output ripple: 10 mVpk-pk

Low Dropout Linear Regulator Circuit Diagram

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5 Volt Switching Regulator Power Supply

The switching regulator power supply used LM2575-5.0 on this schematic.

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Build a Voltage Regulator 12v to 24v using 7812

How to build a voltage regulator 12v to 24v using 7812. What many people do not know is it possible for a voltage regulator IC to provide an output voltage higher than its actual value. One method to achieve this is by connecting the "common" terminal to the middle point of a potential divider, but the problem with this method is that the regulators IC has a small quiescent current (~ 10 mA) flowing out the common terminal to ground.

The schema presented here avoids the problems of using the IC regulator to raise the voltage via the transistor Q1 to generate a low impedance to the common terminal video controller during the transfer of the voltage divider from a resistor divider network relatively high. The value of R3 is not critical, but should be low enough to accept the higher quiescent current without causing problems for T1.

Voltage Regulator 12v to 24v Circuit Diagram 

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Temperature Regulator Circuit with TIP122 Wiring diagram Schematic

For best efficiency,make good thermal contact between the 40 ohm resistor,the TIP 122,the 3 diodes and the temperature controlled entity , the components all give off heat. We have some minor changes to the draft Roy. Roy A 4.7V zener is used in its original design and a resistor network, a range of operating temperatures of 188 degrees Kelvin to 243 Kelvin degrees C or -85 to -30 C.

Temperature Regulator Circuit with TIP122

This is fine in Cryocam Roy, but I’m afraid that many of our camera cookbook may not be able to reach a maximum temperature of Roy. That and the fact that related to the Zener 4.7V difficult to replace me with Roy Z 5.1V zener with more accessible. This diode is available off the shelf at Radio Shack. I supply the resistor network on a range of 190 K to 270 K or -83 C to -3 C I believe that most of our cameras can be maintained to -3 C and I doubt that all our cameras in a position are to be attained – 83 C, so I think that this area should be good enough coverage. I chose to use a 100k pot at some point, because I’m going to the plate with a dual digital potentiometer DS1267 replace. I do not allow for a distance, using Win245 software controllable temperature control and the 100K pot is the control loop is working is to be updated very easily. I intend to use the pot on the remaining DS1267 to replace R43 on the board pre-amp. This allows a selectable gain control software for the camera cookbook. More later.

I would recommend the maximum TEC voltage regulator and leave it there. The schema temperature controller does the rest. You may want to perform delete on the part of the adjustment of supply voltage and tie the totally positive TEC voltage directly at the outlet of the resistors R1 and R2 in parallel with power supply stocks cookbook. There is much room is available for experiment. Roy says that his power TEC does not need to precisely controlled tension, but also be filtered and have less than 10% ripple. So, I think you no harm by not following the proportion of the supply voltage regulation will do Peltier.

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3 A Wide input Adjustable Switching Regulator

The PTN78060 is a series of high-efficiency, buck-boost, integrated switching regulators (ISR) from good old Texas Instruments (TI). The caseless, double-sided package has excellent thermal characteristics, and is RoHs compliant. The PTN78060 devices operate from a remarkably wide input voltage range:

Note that the –A version supplies a negative output voltage. The devices provide high-efficiency stepdown voltage conversion for loads of up to 3 A. The PTN78060 devices are suited to a wide variety of general-purpose applications that operate off 12-V, 24-V, or tightly regulated 28-V dc power, hence are ideal for running low-voltage electronics from a very high power 24-V battery unit salvaged from an electric wheel chair and migrated into a robot.  The output voltage VO can be set to any value over a wide adjustment range using a single external resistor RSET, using the equation RSET = 54.9kΩ×(1.25V/VO–VMIN) – Rp  If pin 4 is left open, the output voltage defaults to the lowest value.

Limiting ourselves to the two positive-output regulators, for the -W version, VMIN and Rp are 2.5 V and 6.49 kΩ respectively; for the -H device, the values 11.824 V and 6.65 kΩ should be used. For the output to remain in regulation, the input voltage must exceed the output by a minimum differential voltage. Another consideration is the pulsewidth modulation (PWM) range of the regulator’s internal control schema. For stable operation, its operating duty cycle should not be lower than a certain minimum percentage. This defines the maximum advisable ratio between the regulator input and output voltage magnitudes. For satisfactory performance, the operating input voltage range of the PTN78060x must satisfy the following requirements.

1. For PTN78060W devices supplying output voltages lower than 10 V, the minimum input voltage is (VO+2 V) or 7 V, whichever is higher.

2. For PTN78060Ws supplying output voltages of 10 V and higher, the minimum input voltage is (VO+2.5 V).

3. The maximum input voltage for PTN78060W is 10VO or 36 V, whichever is less.

4. For PTN78060H output voltages lower than 19 V, the minimum input voltage is (VO+3 V) or 15 V, whichever is higher.

5. For PTN78060H output voltages equal to 19 V and higher, the minimum input voltage is (VO+4 V).

 

As an example, the Table gives the operating input voltage range for some commonly used output bus voltages. The modules are protected against load faults with a continuous current limit characteristic. Under a load-fault condition, the output current increases to the current limit threshold. Attempting to draw current that exceeds the current limit threshold causes the module to progressively reduce its output voltage. Current is continuously supplied to the load until the fault is removed. Once it is removed, the output voltage promptly recovers. When limiting output current, the regulator experiences higher power dissipation, which increases its temperature. If the temperature increase is excessive, the module overtemperature protection begins to periodically turn the output voltage off.

The inhibit feature can be used wherever there is a requirement for the output voltage to be turned off. The power module switches off the output voltage when the Inhibit control (pin 3) is pulled to ground,for example, by a switching FET. Finally, good attention should be paid to the quality of the capacitors on VI and VO as they determine the regulator stability and overall performance to a substantial degree. Summarizing the extensive information on capacitor selection found in the datasheets, the minimum requirement for C1 is 2.2 μF (!) worth of ceramic capacitors for the –W device and 14.1 μF (!!) for the-H device. Tantalum caps are not recommended.  Similarly, at the regulator output, C2 should be at least 100 μF worth of low- ESR electrolytics. 

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