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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50Watt Audio Power Amplifier Circuit with LM3876

My account of architecture of this activity was to advance a bunched architecture for a stereo amplifier can be chip by a amiss (but the complete affection conscious!) Living apprentice at a university or a academy dormitory.

The amplifier feeds a brace of speakers with two LM3876 amplifier chip circuits (50 watts per channel), or a brace of headphones Meier Crossfeed through a clarify and a bifold OPA2134 Opamp. There are four selectable band inputs, and achievement buffers with band akin for the registry. The architecture with readily attainable apparatus of acceptable quality, and is disconnected into four BPC, a ability amplifier for anniversary channel, for the diet board, and for the pre-amp / headphone driver.

The achievement selector is beatific to pins J1 and J3. Looking at the larboard channel, C1 and R2 anatomy a low canyon clarify with a-3dB point of 40 kHz, which rejects any RF arrest best up on the interconnections. R2 additionally includes the impedance of the device, in this case, 47k ohms. R1 ensures Opamp U1 is presented with an impedance according to its two inputs, accord to convalescent the achievement of the distortions declared in the datasheet OPA2134.

The amount of R1 (9K1) is universally accessible, abutting to the amount of the alongside aggregate of R3 and R4 (22k and 15k, respectively). R3 and R4 set the accretion at that time, aloof beneath 2.5 in this case. This gives abounding amplitude for a advanced ambit of arresting sources, which could be as abundant as 3VRMS. In this case, the aiguille achievement voltage of 10.6V would be accomplished with the activity to accumulation ± 15V.

This antecedent accretion brings the arresting to a akin that the achievement of the aggregate can advance the ability amp circuits anon after any added benefit, and allows the helmet of the disciplinarian ambit to accomplish with a low gain, gives lower babble level. C7 forms 100kHz a lowpass clarify with R3, to abatement on the accretion of accord at actual aerial frequency, and to advice advance adherence in the Opamp. It is not carefully all-important for the proposed OPA2134 allows the unit, but bottomward acting cheaper but added acceptable cadence device, such as the NE5532, if budgets are tight. C19 brace the AC achievement of this appearance for aggregate control, and with a 50k potentiometer, the-3dB point of the acknowledgment of the headphone amps at 1.4Hz (power amp has added HIGH PASS FILTER). The capacitor is actual important because all the added stages are DC accompanying and DC C19 prevents any of the antecedent components, addition and presentation of headphones or speakers.

Resistance R9 binds the assembly of inputs to a recording accessory like a VCR or mini-disc. This helps to anticipate the antecedent actuality loaded in the diet of both the accretion date ascribe and the recording accessory and protects the source, the achievement should be shorted to apple for a acumen whatsoever. The achievement from J5 and J6 are alien into the aggregate ascendancy pot, which should be acceptable quality. Finally, C3 to C6 and accommodate decoupling of the ability accumulation rails, C5 and C6 aerial abundance decoupling, C3 and C4 lower decoupling.

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TL783C based 48V PHANTOM POWER SUPPLY circuit with explanation

This is a simple 48 V regulated linear power supply design that will provide up to 60 mA of current. This circuit is based on the Texas Instruments TL783C high voltage adjustable linear regulator IC, because this device will provide short circuit protection for an input to output differential voltage of up to 125 V. AnLM317T can also be used in this circuit, but a short on the output will destroy the regulator IC. Protective diodes are included in this design to provide a discharge path around the regulator in case of an accidental reverse bias condition.

Part :
C1,C2,C3 – 220 uF 100 V
C5,C6 -10 uF 100 V
C6 -10 uF 100 VD1-D6 – 1N4002
R1 – 82 OHM 1/4 W
R2 – 1 K OHM TRIMMER
R3 – 2.7K OHM 1 W
T1 – 40 V at 0.15 A (6 VA)
U1 – TL783C

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transformerless power supply circuit

1- transformerless power supply circuit 11 volts

Parts :

C1 = 0.39uF 250V Capacitor

C2 = 220uF 25V Electrolytic Capacitor

D1 = 1N4741 11V Zener Diode

BR1 = 1 Amp 200V Bridge Rectifier

2 - TransformerLess Power Supply circuit 12V 100mA

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HANDY 0 12V DC POWER SUPPLY ELECTRONIC DIAGRAM

HANDY 0-12V DC POWER SUPPLY ELECTRONIC DIAGRAM

For heat protection, heat sink is needed for the BD679 transistor. It is because it will be over tempered when works more than 200mA.

FEATURES:
0v to 12 volt output:
- 700mA with M 2155
- 1.4amp with M 2156
- 1A with 16v AC 1.5 amp plug pack

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RESISTOR TO REDUCE L200 POWER DISSIPATION ELECTRONIC DIAGRAM

RESISTOR TO REDUCE L200 POWER DISSIPATION ELECTRONIC DIAGRAM

Instead of in series with the input, the resistor R can be connected between pins 1 and 2 of the IC if the load is constant. You can see this in the right figure. This will make some part of the load current flows through the resistor and the other part through the device.

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275W RMS Power Amplifier

The 275W RMS Power Amplifier design includes not simply the final stage of the source (rectifier, filter) and protection aligned with DC voltage output amplifier and spokeswoman links delayed. like already mentioned, the amplifier is designed as a single-module. This instrument so as to on individual universal board rectifier, filter capacitors, protection And beyond doubt amplifier. This transistor provides a thermal criticism and along these lines of a committed quiescent current amplifiers. Privacy speakers are powered immediately from the voltage amplifier. for example pro mechanical design, is probably the a good number complicated now the in one piece amplifier. Cooling is through by the Al blocks with the purpose of are attached to the highest cooling profile. ZH6465 profile is used. The terminal transistors to section is released through Al strips with a thickness of 6 mm in the lateral beams and momentary into the cooler. other pictures.

Circuit Diagram 275W RMS Power Amplifier Click image to view High Resolution

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Soft Start For Switching Power Supply

Switching power supply whose output voltage is appreciably lower than its input voltage has an interesting property: the current drawn by it is smaller than its output current. However, the input power (UI) is, of course, greater than the output power. There is another aspect that needs to be watched: when the input voltage at switch-on is too low, the regulator will tend to draw the full current. When the supply cannot cope with this, it fails or the fuse blows. It is, therefore, advisable to disable the regulator at switch-on (via the on/off input). until the relevant capacitor has been charged. When the regulator then starts to draw current, the charging current has already dropped to a level which does not overload the voltage source.

Soft Start For Switching Power Supply  Circuit diagram:

Soft Start Circuit For Switching Power Supply

The circuit in the diagram provides an output voltage of 5 V and is supplied by a 24 V source. The regulator need not be disabled until the capacitor is fully charged: when the potential across the capacitor has reached a level of half or more of the input voltage, all is well. This is why the zener diode in the diagram is rated at 15 V. Many regulators produced by National Semiconductor have an integral on/off switch, and this is used in the present circuit. The input is intended for TTL signals, and usually consists of a transistor whose base is accessible externally. This means that a higher switching voltage may be applied via a series resistor: the value of this in the present circuit is 22 kΩ. When the voltage across the capacitor reaches a level of about 17 V, transistor T1 comes on, whereupon the regulator is enabled.

Source: National Semiconductors

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Power Amplifier MOSFET 360 W

I propose here a more powerful version of the 200 Wrms 8 ohms AB class power amplifier project. It shares the same concept that the less poweful model : assembled using common compoments (not very expensive), based on traditional diagrams : a symmetrical differential input stage, a cascode stage driver and a MOSFET output stage. The printed circuit board is very compact , and is composed of two subsets : the command stage and the output stage. All resistors are 1/4 watt 1 % metal film (except if otherwise stated). Constant current sources of +/- 1 mA are formed around T5 and T6. The diodes D1 to D6 allow the use of low noise transistors type BC550C and BC560C, the transistors T7 to T10 form the stage driver. The potentiometer P1 allows the adjustment of the quiescent current to 100 mA per output transistor. The symmetrical power supply is entrusted to a large transformer of 750 VA, 2 * 60 volts + bridge rectifier and 8 reservoir capacitors of 4700 µF, which gives an output voltage of + and - 85 volts per rail. A 1000 VA transformer is necessary for maximal continuous output power at 4 ohms. The output power is 360 Wrms under 8 ohms or 550 Wrms under 4 ohms. Distortion is lower than 0,02 %, damping factor is better than 400, signal-noise ratio is 112 db (balanced A at full power), the input sensitivity is 1,2 volts (360 W under 8 ohms).

Diagram : 

The capacitor C3 is not reproduced on the diagram and on the PCB (it is correct).

Proposal of the command stage PCB : 

 
Transistors T9 and T10 must be assembled on a common heatsink with 5° c/w thermal resistance or on the output stage heatsink.

Proposal of the output stage PCB : 

 The points marked A, B and C have to be connected between the two PCBs. The ground (earth) points of PCBs and loudspeaker ground (earth) must compulsorily be connected in star with the 0 Volts of the PSU. The power transistors must be assembled on a heatsink with a termal resistance less than 0.5 ° C/W. They must also be electrically insulated from the heatsink by using a mica insulator + heat-conducting compound or a silicone insulator.

Bandwidth : 

Bandwidth is limited from 5 Hz to 53 Khz (at - 3 db) by the input module (C1, R1, C2, R2). It can be modified according to the application desired. It is useless to increase the bandwidth to the botton (bass) because little useful signal is present at the bottom of the spectrum. In public address sound systems the bandwidth is often limited between 20 and 35 Hz. The loudspeakers are thus protected against too high extreme-bass signals and some more power is available for the remainder of the spectrum. Michael Eveleigh (UK)

 Source : http://users.swing.be/edwinpaij/ampli_mosfet_360_w.htm

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Mosfet Power Amplifier 100 Watt

At this time a unsophisticated MOSFET amplifier or else power Amp which Output power is plus/minus 100 Watt/RMS with 8 Ohms otherwise ohter plus/minus 160 Watts /RMS with 4 ohms.

Mosfet Amplifier 100 Watt RMS

Regarding this circuit simplicity, The distortion is plus/minus 0.1 %. In support of mob-width -3 db(decibel) is increase for 4 Hz to 96 Khz, it is narrow by C1, R1, C2 and R2. Taking part in the two transistors are T1 and T2 makes a initial differential stage part, So,current source(I) of +/- solitary mA is put with resistor R3. In favor of the upgraded project, The current source(I) is new efficient in stability. Coil P1 allows a fine tuning of dictate current voltage on amplifier’s output. Place the Coil P1 with it’s partially usefulness in favor of first power up, so therefore break it unhurriedly for a lowest DC output voltage. custom a essential quality compoment.

Electronic Part

C1 = 2,2 µF MKP, MKT 100 in opposition to

C2 = 330 pF céramique 50 V

C3 = 100 nF MKP, MKT 100 in opposition to

C4 = 100 µF 40 V électro-chimique

C5, C6 = 18 pF céramique 50 vs.

C7 = 100 nF MKP, MKT 250 V  (C8 = 47 µF 100 V)

R1, R3 = 47 K   (R3 = 330 -> 470 Ohms)

R2 = 2K2

R4, R5 = 3K9

R6 = 1 K

R7 = 27 K

R8, R9, R11 = 100 ohms

R10 = 10 K

R12, R13 = 470 ohms

R14, R15 = 0.33 ohms 5 watts

R16 = 10 ohms 3 watts      (R17 = 1 K    R18, R19 = 10K)

T1, T2, T9,T10 = 2SD756A,2SD716A, BC556B (attention au brochage différent - take be concerned representing pin arrange)

T7 = IRFP240, 2SK1530, 2SJ162, BUZ900DP, BUZ901DP (attention au brochage dissimilar - take care for pin layout : GDS GSD)P1 = 100 ohms  (25 turns - 25 turns)

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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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200W power amplifier complete power supply

This 200W power amplifier circuit using IC STK 4050.
STK 4050 is a power amplifier module is very powerful, because the IC is already a module then only needed a little extra components to build a reliable 200W Power Amplifier. Here is a picture series of Power Amplifier ICs 200W use STK 4050 complete with its power supply:

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0 30V power supply bench variable

Today I seeks variable power supply circuit come to deposit again. Which be the circuit that use base equipment, build not difficult follow the circuit can fine volt get 0-30V , give current get about 1-2A depend on transformer at you choose to use.

The prominent point of the circuit use transistor join a pin BE replace Zener Diode. Then get around problems about seek buy Zener voltage that can’t want. By transistor at use 2N3638 numbers or the number replaces. For transistor output use 2N3055 durable numbers current not exceed 2A. 

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3A Adjustable 3 30V Regulated DC Power Supply

This power supply is meant as an auxiliary or as a permanent power supply for all common circuits based on a stabilized DC voltage between 3 and 30V provided that the consumption does not exceed 3A. Of course this power supply unit can also be used for other purposes. Be replacing the trimmer by a potentiometer, it may even be used as an adjustable power supply unit. A good quality heatsink must be used.
[...]
Parts list:
R1 = 8.2K
R2 = 2.2K
R3 = 680R
R4 = 1K
R5 = 82K
R6 = 0.18R/5W
C1 = 470p
C2 = 100nF-63V
C3 = 100nF-63V
C4 = 100uF-63V
C5 = 10KuF-60V
D1-D6 = 6.6A
Q1 = MJ3001 (Darligton)
IC1 = UA723D
Specifications:
* Overload protected
* Sshort-circuit stable
* Output current: max. 3A
* Output ripple voltage: 0.5mV
* Output voltage: adjustable from 3 to 30V, stabilized
* Input voltage: 9 to 30V AC (depending on the desired output voltage)

Source: http://www.extremecircuits.net/2010/02/3-30v-3a-adjustable-regulated-dc-power.html

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Sensitive Audio Power Meter Circuit Diagram

As a follow-up to the simple audio power meter described in [1], the author has developed a more sensitive version. In practice, you rarely use more than 1 watt of audio power in a normal living-room environment. The only time most people use more is at a party when they want to show how loud their stereo system is, in which case peaks of more than 10 W are not uncommon. With this circuit, the dual LED starts to light up green at around 0.1 watt into 8 ohms (0.2 watt into 4 ohms). Naturally, this depends on the specific type of LED that is used.

 
Sensitive Audio Power Meter Circuit diagram:

Sensitive Audio Power Meter Circuit Diagram

 

Here it is  essential to use a low current type. The capacitor is first charged via D1 and then discharged via the green LED. This voltage-doubler effect  increases the sensitivity of the circuit. Above a level of 1 watt, the transistor limits the current through the green LED and the red LED con ducts enough to produce an orange hue.The red colour predominates above 5 watts. Of course, you can also use two separate ‘normal’ LEDs. However, this arrangement cannot generate an orange hue. For any testing that may be necessary, you should use  generator with a DC-coupled output. If there is a capacitor in the output path, it can cause misleading results.

Reference: Simple Audio Power Meter, Elektor July & August 2008.

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by 2N3055 Power Supply Voltage Adapter for Car

A car voltage generally is 12 Volts. How about when you want to connect non 12 volts devices into your car? The circuit here is the solution. Even the circuit is design for a car apppliance, it does not seem it can’t be used for another purpose.

 

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Dual Regulated Power Supply Circuit Diagram

In this circuit, the 7815 regulatates the positive supply, and the 7915 regulates the negative supply. The transformer should have a primary rating of 240/220 volts for europe, or 120 volts for North America. The centre tapped secondary coil should be rated about 18 volts at 1 amp or higher, allowing for losses in the regulator. An application for this type of circuit would be for a small regulated bench power supply. 

 Dual Regulated Power Supply Circuit Diagram

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Simple 22W Amplifier for 12V Power Supply Systems

This is a 22-W Amplifier circuit that is designed for or 12-V DC power supply Systems. There are many application for  this circuit,  such as in car audio  application. In car electrical  power supply system, the 12V power supply will be provided by the host vehicle’s battery. 

The capacitor C3 is used to give ripple rejection, since noisy power supply voltage is common in automotive electrical system. The power supply noise signal on car power supply is decoupled by the capacitors C2 and C1.  Smaller capacitor C2 is needed to decouple the high frequency noise, since the larger cap (C1) usually has high equivalent series inductance that prevent the high frequency noise  (such as glitch or spike) to be bypassed. 

The capacitors C5 couple the incoming audio signal to IC1 while decoupling static DC offset. For better bass response, this circuit prevent rolling off of the low audio frequencies by choosing a relatively large capacitance for small signal, 10μF capacitors. Here is the schematic diagram of the  circuit.

 22W Amplifier for 12V Power Supply Systems Circuit Diagram

This circuit prevent power supply pop noise by muting the amplifier at the power-up. The mute input (pin 14) is fed by capacitor C6 and Resistor R1, giving delay on power-up which prevent  turn-on pop. This  R/C time constant gives about 1.4s delay to keep the output muted,  enough to make sure the amplifier reach the stable state after powered up.  

About how this muting works, the amplifier will be ON if pin 14 has at least 8.5 V. The chip will remain in muted condition if the voltage at this pin is below 3.3V.  This input pin need very low current consumption, only about 100 pA for standby (muted)  and around 40 pA when active. The R1 values must be no larger than 100,000  Ω. The R1/C6 constant should be on the second order. If time constant is too short, the turn-on pop will still be heard, but too long  time constant will give unpleasant delay.

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Build a 60W Transistored Power Amplifier Circuit Diagram

This is the circuit diagram of 60W transistored power amplifier. This circuit was designed and built during the 80s. From then it works without problem. It does not present a particular construction problem, apart from the known: the attention to the supplied power source, choosing suitable heatsinks and good matching of the driver transistors. The diodes D3..5 should be placed on the heatsinks of power transistors to have thermal coupling with the output transistors.

 60W Transistored Power Amplifier Circuit Diagram

With the trimmer R15, we regulate the voltage at the output of the amplifier [with long work hours and little heat stabilized]. With the trimmer TR1, we can adjust the bias current of the amplifier at 50 to 100 mA. The bias current can be measured if you measure the voltage drop at the ends of the resistors R36 and R37, for the voltage that are given in the circuit, the current is approximately 75 mA. The voltage indicated in above diagram can be different, but may have a tolerance of about +/- 10%.

Parts List

R1 = 1.8K ohm	R25 = 8.2K ohm	D1,D2 = 24V/1W Zener	C1 = 4.7uF/25V
R2 = 220K ohm	R26 = 27K ohm	D3….9 = 1N4002	C2 = 470pF
R3 = 27K ohm	R27 = 820 ohm	T1-2 = BC550C	C3-4 = 100uF/63V
R4,R10,R11,R17 = 3.3K ohm	R28 = 3.3K ohm	T3,T4 = BC560C	C5 = 68pF
R5,R9,R12,R16 = 100 ohm	R29 = 100 ohm	T5,T13 = BD530	C6,C10 = 330pF
R6 = 18K ohm	R31,R39 = 180 ohm	T6,T8 = BC414C	C7 = 22pF
R7,R13 = 3.9K ohm	R32,R38 = 6.8K ohm	?9 = BC416C	C8 = 220uF/16V
R14 = 10K ohm	R33,R34 = 1.2K ohm	T7,T10 = BD529	C9 = 100nF 100V
R15 = 22K ohm Trimmer	R35 = 82 ohm /1W	T11 = BD591	C11,C12 = 10pF
R18,R23 = 330 ohm	R36,R37 = 0.33 ohm / 5W	T14 = BD592	C13,R15 = 47uF/63V
R19,R21,R22 = 15K ohm	R40,R41 = 10 ohm / 2W	T12 = 2N5630	C16,R17 = 100nF/100V
R20 = 12K ohm	R42 = 180 ohm/5W	T15 = 2N6030	C18,R19 = 100nF/100V
R24,R30 = 82 ohm	TR1 = 4.7K ohm Trimmer

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3000 6000 MHz 50 Watts High Power Amplifier

The BBS26A8CHM ruggedized amplifier system is our latest in microwave solid-state amplifiers. This compact and lightweight system features high power output and excellent efficiency. This amplifier utilizes high power GaN devices. It fits in standard 19-inch equipment racks, weighs less than 70 lbs and is available with or without touch-screen LCD control, Ethernet connectivity and a full range of other options including 400 Hz aircraft power

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