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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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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1 5Volt Led using 555 IC

1.5Volt Led using 555 IC

This LED circuit is powered only by the cell of 1.5 V with IC 555. The timer IC is used in astable mode similar to the double-circuit voltage, which is the step from 1.5V to about 2.5V. The frequency of the circuit is about 60 Hz and consumes very little left that is not a problem.

Part List:

R1- 39 kilo-ohms
R2- 100 kilo-ohms
R3-10 ohms but if no light or very dim, just short it
C1- 100nF
C2- 10nF
C3- 220uF electrolytic capacitor
C4- 100uF electrolytic capacitor
D1- preferably schotky diode but ordinary diode like 1N4001 will do
555- use the CMOS type 555
LED- red, yellow and other low power led (do not use white or blue)
1.5V- any 1.5V battery

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Accu charger with IC LM723C

Circuit of 12 V accu / battery charger with IC LM723C. This Accu charger have input from the first transformer - voltage 220 initially V/110V/240V,  the input voltage lowered approximately 12 VAC, then voltage 12 Volts will be rectified by D1 and then filtered by C1 , then filtered and amplified again by IC LM723 and NPN transistor , output voltage is ready to use to charging the accu / battery.

Accu charger with IC LM723C

Part list :

T1 = Transformer , DC 12 V

D1 = Diode bridge

C1 = 470uF /50V

C2 = 1000pF

R1 = 4R7

R2 = 5K

R3 = 3K9

R4 = 7K5

R5 = 8K2

VR = 2K - 5K trim

TR1 = MJ2840

IC = LM723C

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Schematic Audio Power Amplifier with IC TDA2822

TDA2822 is manufactered by PHILIPS , its based on this amplifier . Minimum voltage 3 volts and maximum voltage 15 volts. Power output 2 x 1,8 stereo with 4 Ohm impedance. Quiescent current 6 mA , sensitive input is 30 Hz to 18 kHz. See circuit diagram below :

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120 Watt power amplifier with IC TDA2025

Minimum voltage require 12 Volts and maximum voltage require 40 Volts DC . This circuit is very simple , but output is very high . Power output 120 Watt 4 Ohm impedance. See circuit below :

TDA2025 Very high intregated Power IC

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NE555 IC Timer

The 555 Timer is an integrated circuit (chip) implementing a variety of timer and multivibrator applications. The IC was designed and invented by Hans R. Camenzind. It was designed in 1970 and introduced in 1971 by Signetics (later acquired by Philips). The original name was the SE555/NE555 and was called "The IC Time Machine".

The 555 gets its name from the three 5-k Ohm resistors used in typical early implementations. It is still in wide use, thanks to its ease of use, low price and good stability. As of 2003[update], 1 billion units are manufactured every year.

The 555 timer is one of the most popular and versatile integrated circuits ever produced. It includes 23 transistors, 2 diodes and 16 resistors on a silicon chip installed in an 8-pin mini dual-in-line package (DIP-8).

The 555 has three operating modes:

* Monostable mode: in this mode, the 555 functions as a "one-shot". Applications include timers, missing pulse detection, bouncefree switches, touch switches, Frequency Divider,Capacitance Measurement, Pulse Width Modulation (PWM) etc

* Astable - Free Running mode: the 555 can operate as an oscillator. Uses include LED and lamp flashers, pulse generation, logic clocks, tone generation, security alarms, pulse position modulation, etc.

* Bistable mode or Schmitt trigger: the 555 can operate as a flip-flop, if the DIS pin is not connected and no capacitor is used. Uses include bouncefree latched switches, etc.

The connection of the pins is as follows:

Nr. Name Purpose

1 GND Ground, low level (0V)

2 TR A short pulse high → low on the trigger starts the timer

3 Q During a timing interval, the output stays at +VCC

4 R A timing interval can be interrupted by applying a reset pulse to low (0V)

5 CV Control voltage allows access to the internal voltage divider (2/3 VCC)

6 THR The threshold at which the interval ends (it ends if U.thr → 2/3 VCC)

7 DIS Connected to a capacitor whose discharge time will influence the timing interval

8 V+, VCC The positive supply voltage which must be between 3 and 15 V

In the astable mode, the high time from each pulse is given by

high = 0.693.(R1 + R2).C

and the low time from each pulse is given by

low = 0.693.R2.C

where R1 and R2 are the values of the resistors in ohms and C is the value of the capacitor in farads.

Specifications

These specifications apply to the NE555. Other 555 timers can have better specifications depending on the grade (military, medical, etc).

* Supply voltage (VCC) 4.5 to 15 V

* Supply current (VCC = +5 V) 3 to 6 mA

* Supply current (VCC = +15 V) 10 to 15 mA

* Output current (maximum) 200 mA

* Power dissipation 600 mW

* Operating temperature 0 to 70 °C

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Skema Audio Power Amplifier with IC AN7106K

This Schematic must use the IC AN7106 because itsnt similarity, and some components. Minimum voltage is 1,8 Volt and Maximum voltage is 4,8 volt . It,s so very low voltage require. Recomended voltage is 3 volt , dont provide voltage too high it can make damage IC. Maximal Output 2 X 0,14 watt , this is stereo amplifier. And impedance is 32 Ohm.

See Schematic and package IC AN7106K below :

Package IC DIP24

Click Image to view enlarge.

 Good Luck !!

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Audio IC TDA1013 4 5W

Circuit diagram IC TDA1013 4.5W:

Audio IC TDA1013 4.5W

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Multiplexer with TTL IC 74251

Actually you can not bother to design a multiplexer using logic gates because it has many special IC which functioned for a multiplexer.

One of the TTL ICs from the family that you can use to fulfill the function of a multiplexer is IC 74 251. At the IC there are 8 input channels and 3-bit selector and the other lane as a control reset and inverting output. As a note if you are using TTL ICs for your electronic circuit, the voltage supply that is allowed a maximum of 5 volts. So you can be more familiar with the workings of this multiplexer ic, IC74251 consider the truth table below:

C	B	A	G	Y	W
X	X	X	1	Z	Z
0	0	0	0	D0	D0’
0	0	1	0	D1	D1’
0	1	0	0	D2	D2’
0	1	1	0	D3	D3’
1	0	0	0	D4	D4’
1	0	1	0	D5	D5’
1	1	0	0	D6	D6’
1	1	1	0	D7	D7’
Z = High impedance (off)
D0,D1…D7 = Representing the output of the input lines D

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Schematic Audio Amplifer with IC AN315

This Schematic Require voltage 9 - 18 Volt. Good voltage for this schematic is 12 V. This is Mono amplifier with output 5,5 Watt and impedance 8 Ohm. You can make this Circuit easily because i give simple and clear scheme.

See this Schematic and Datsheet IC AN315 :

Click to Enlarge

Datasheet IC AN315

Vcc                = 9-18 V

Pout               = 5,5 W

RL                  = 8 Ohm

Ft                   = 30hz - 18Khz

Icco                = 28 mA

Package         = SIP2-11

Manufactered = MATSUSHITA

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Single IC Dual tones Siren Circuits Wiring diagram

Double-tone Police sound Circuits Diagram

This schema is intended for children fun, and can be installed on bicycles, battery powered cars and motorcycles, but also on models and various games and toys. With SW1 positioned as shown in the schema diagram, the typical dual-tone sound of Police or Fire-brigade cars is generated, by the oscillation of IC1A and IC1B gates. With SW1 set to the other position, the old siren sound increasing in frequency and then slowly decreasing is reproduced, by pushing on P1 that starts oscillation in IC1C and IC1D. 

The loudspeaker, driven by Q1, should be of reasonable dimensions and well encased, in order to obtain a more realistic and louder output. Tone and period of the sound oscillations can be varied by changing the values of C1, C2, C5, C6 and/or associated resistors. No power switch is required: leave SW1 in the low position (old-type siren) and the schema consumption will be negligible.

Single -IC Dual-tones Siren Circuits Diagram

Parts:

R1,R3___470K1/4W Resistors

R2______680K1/4W Resistor

R4_______82K1/4W Resistor

R5______330K1/4W Resistor

R6_______10K1/4W Resistor

R7_______33K1/4W Resistor

R8________3M31/4W Resistor

C1,C5_____10µF25V Electrolytic Capacitors

C2,C6_____10nF63V Polyester Capacitors

C3_______100nF63V Polyester Capacitor

C4_______100µF25V Electrolytic Capacitor

D1-D3___1N414875V 150mA Diodes

IC1_____4093Quad 2 input Schmitt NAND Gate IC

Q1______BC33745V 800mA NPN Transistor

P1______SPST Pushbutton

SW1_____DPDT Switch

SPKR____8 Ohm Loudspeaker

B1______6V Battery (4 AA 1.5V Cells in series)

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Car Amplifier with IC LA4445

This circuit using IC LA4445 , this is stereo amplifier with power output 2 X 18 Watt, with this circuit you can use to car amplifier or to other elctronics device. Speaker use woofer with impedance 4 Ohm with power up to 20 Watt. Minimum voltagte require 10 Volt and maximum voltage 18 volt.

Car Amplifier with IC LA4445

If you cant operate the circuit , please check IC , and then voltage in. If voltage is good check the component are. If components are working . Please check speakers.

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How to Treble and Bass Control without IC or Transistor

This Treble and Bass Control without IC or Transistor schema consists of bass and treble just a few capacitors, resistors and two potentiometers to adjust BASS and TREBLE. The schema is very functional, can be used to adjust the small sound amplifiers. And control Treble and works relatively well. The interesting thing is that this control does not use or IC or transistor.

Treble and Bass Control without IC or Transistor Circuit Diagram

How to Treble and Bass Control without IC or Transistor

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