TDA1562Q Audio Power Amplifier 36 Watt

The TDA1562Q Audio Power Amplifier 36 Watt based on a Philips class-H audio amplifier IC and can deliver 36W RMS OR 70W music power, all from a 13.8V supply. Our new Mighty Midget Amplifier can really pack a punch - around 36W RMS continuous into a 4-ohm load when using a 13.8V supply. However, it's the 70W of output power that it can deliver during dynamic (music) signal conditions that really make you sit up and take notice.

TDA1562Q Audio Power Amplifier 36 Watt

As can be seen from the photos and the circuit diagram, the Mighty Midget uses just a handful of parts. It's built on a PC board that measures just 104mm x 39mm but while its size may be modest, these's nothing at all modest about its power output. And the noise and distortion figures are pretty good too.

Circuit diagram:
36 Watt Audio Power Amplifier Circuit Diagram
Figure 2. 36 Watt Audio Power Amplifier Circuit Diagram

At the heart of the circuit is the TDA1562Q IC, described by Philips as a "monolithic integrated Bridge-Tied Load (BTL) class-H high-efficiency power amplifier". It comes in a 17-pin "DIL-bent-SIL" plastic package and is not only designed for use in car audio and portable PA work but for mains applications as well; eg, mini/midi audio components and TV sound.

TDA1562Q Audio Power Amplifier 36 Watt Performance:

* Output power:36W RMS into 4R
* Music power:70W into 4R
* Frequency response:1dB down at 28Hz and 55kHz
* Input sensitivity:130mV RMS (for 36W into 4?)
* Harmonic distortion:typically 0.2% (see graphs)
* Signal-to-noise ratio:95dB unweighted (22Hz to 22kHz)

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Integrator Using Op amp 741 Circuit

An integrator is a circuit which shows the sum of input voltage at the output. That means it works by the operation of integral form. If we see the output of the integrator shows the summation of input voltages, the result of integrator circuit will be right. Such that, if we give square wave at the input, then we will get triangular wave at the output. A circuit in which the output voltage waveform of Op amp is the integral of the input voltage waveform is the integrator or the integrator amplifier. Such a circuit is obtained by using a basic inverting amplifier configuration if the feedback resistor RF is replaced by a capacitor CF.

Integrators are used in the design of signal generators and signal processing circuits. It is also used in analog computers and analog-to-digital (ADC) and signal-wave shaping circuits. When Vin = 0, the integrator of Fig 1(a) works as an open-loop amplifier. This is because the capacitor CF acts as an open circuit (XCF = ∞) to the input offset voltage Vio. In other words, the input offset voltage Vio and the part of the input current charging capacitor CF produce the error voltage at the output of the integrator.

Therefore, in the practical integrator to reduce the error voltage at the output, a resistor RF is connected across the feedback capacitor CF. Thus, RF limits the low-frequency gain and hence minimizes the variations in the output voltage. Both the stability and the low-frequency roll-off problems can be created in ideal integrator. Those problems can be corrected by the addition of a resistor RF. From the simulation result, we can see that the output of square wave is the triangular wave. So, we can say that integrator does the sum at the output.
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PIC16F684 Digital Ammeter

The bellow circuit is digital Ammeter based on PIC16F684 and ACS712 current sensor. Here the measured ac/dc current will display on three digit 7-segment with resolution 100mA. In this project current sensor is ACS712ELCTR-30A-T . This circuit can measure the ac or dc current up to 30mA with 66mV/A output sensitivity.

The micro-controller PIC16F684 is used to read analog value from the ACS712 current sensor output and micro-controller convert to current and displaying on 7-segments display. For this circuit all 7-segment displays will be common anode type and it driven by PNP transistor BC557. Originally, this circuit is suitable for measuring DC current.
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BC548 Heat Sensor Circuit

Heat sensor circuit can be used to control any device using heat sensor. In this circuit a thermistor and a resistance is connected in series. This arrangement makes a potential divider circuit. Here the thermistor is Negative Temperature Coefficient type. So when the room temperature is increased its resistance decreases simultaneously and more current flows through the resistor and the thermistor. We find more voltage at the junction of the resistor and the thermistor.

Our thermistor resistance value is 110 ohms. Suppose the resistance value becomes 90 ohms after heating the 110 ohms thermistor. Then the voltage across one resistor of the voltage divider circuit equals the ratio of that resistor’s value and the sum of resistances of the voltage across the series combination. This is the concept of voltage divider.

The final output voltage of the voltage divider circuit is now applied to the npn transistor (BC548) through the base resistor (3.3K ohms). Here the emitter resistor is replaced with a zener diode. Emitter voltage is maintained at 4.7volt with the help of zener diode. This voltage is used to compare voltage. Transistor conducts when base voltage is greater than the emitter voltage. Transistor conducts if it gets more than 4.7volt of base voltage. Then the circuit is completed through buzzer and it gives sound.
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NE 555 & LM 567 Remote Control Circuit

Remote control circuit consists of two parts, one is transmitter and the other is receiver. A simple diagram is schematic remote control. The transmitter circuit’s transmitter IC is controlled by NE555. Receiver circuit works by the signal emitted frequency which is emitted by that transmitter circuit. Transmitted signal frequency must be equal to the frequency decoder of the receiver circuit. The NE 555 generated frequency is same that receive frequency of IC LM 567. 

The output frequency of the transmitter circuit is f,
f = 1.44/(Ra+2Rb)C
           The resistor R1 is a receiver variable to facilitate the process of tuning. The system works well when the circuit is ready. The first step is tuning by way of the transmitter is turned on continuously, while the receiver R1 to set the value to be able to detect the signal transmitter. The second part is the receiver is controlled by LM 567. The following is a schematic drawing recipient.

f = 1 / (1.1 xR1xC1)
This frequency depends on the value of R1 and C1.

In the picture on top of each channel is designed with a different frequency. By considering the bandwidth of the frequency detection signal LM 567, inter-frequency channels should have a big enough difference, let’s try with a difference of 5 KHz.
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