Schematic Diagram 4in1: 100W RMS Power Amplifier With VU, Power Supply and Tone Control

Part Lists

Active Components

• IC TDA 7294 : 1
• IC 7812 : 1
• IC LM3914 : 1
• Diode Zener 12V : 2
• IC 4558 : 1
• Diode 1N4148 : 1
• Rectifier Bridge Diode 6 A : 1
• LED : 11

Resistors

• 390 Ω – 1/4w : 1
• 680 Ω – 1/4w : 1
• 1K Ohm – 1/4w : 2
• 2k2 Ohm – 1/4w : 3
• 2k7 Ohm – 1/4w : 1
• 3k3 Ohm – 1/4w : 1
• 5k6 Ohm – 1/4w : 1
• 8k2 Ohm – 1/4w : 1
• 10K Ohm – 1/4w : 4
• 20K Ohm – 1/4w : 2
• 22K Ohm – 1/4w : 3
• 30K Ohm – 1/4w : 1
• 47k Ohm – 1/4w : 1
• 10R ohm – 1/4w : 1
• 56R Ohm – 2w : 1
• 2K2 Ohm – 2w : 2
• Potensiometer 50K Ohm : 3

Capacitors

• 100pF nonpolar capacitor disc / ceramic : 2
• 6n8F nonpolar polyester capacitor : 2
• 10nF nonpolar polyester capacitor : 2
• 100nF nonpolar polyester capacitor : 6
• 220nF nonpolar polyester capacitor : 1
• 2.2uF/63V electrolytic capacitor : 1
• 10uF/63V electrolytic capacitor : 5
• 22uF/63v electrolytic capacitor : 2
• 100uF/63V electrolytic capacitor : 2
• 4700uF/63V electrolytic capacitor : 2

100W RMS Power Amplifier PCB Layout

Component Placement

This is a single channel (mono) audio system. For stereo audio system, you need two similar circuit and make some changes such as: use higher transformer current, higher diode current, higher capacitor value for the power supply module. Use only one power supply. Use stereo potensiometer and connect to the two boards using cable.

120W Power Amplifier Part List

Transistors

• 2N3055 (substitution: MJ15003 or 2N3772) : 2
• MJ2955 (substitution: MJ15004 or 2N3771) : 2
• TIP42 : 2
• TIP41 : 1
• 2SC2229 or 2SC2230 or C1573 : 2
• A1015 or A872 or A733 : 2

Capacitors

• 100uF/50V electrolytic capacitor: 2
• 470nF (474) nonpolar polyester capacitor: 1
• 100pF (101) nonpolar ceramic capacitor : 2
• 470pF (471) nonpolar ceramic capacitor : 2
• 10pF nonpolar ceramic capacitor : 2
• 100nF (104) 100V nonpolar polyester capacitor : 2

Resistors

• 0.33 Ω (5W) : 4
• 10 Ω to (1W) – brown, black, black : 1
• 100 Ω (1W) – brown, black, brown : 2
• 33 Ω (1/4W) – orange, orange, black : 1
• 150 Ω (1/4W) – brown, green, brown : 3
• 10KΩ (1/4W) - brown, black, orange : 1
• 1KΩ (1/4W) - brown, black, red : 1
• 4.7KΩ (1W) - yellow, violet, red : 1
• 68KΩ (1/4W) - blue, gray, orange : 1
• 56KΩ (1/4W) - green, blue, orange : 1
• 33KΩ (1/4W) – orange, orange, orange : 1
• 3.3KΩ (1/4W) – orange, orange, red : 2

Diodes

• 3A Diode 1N5404 : 2
• 1A Diode 1N4007 : 3
• Zener diodes between 20 and 24 volts : 1

Others

• 3A fuse
• small 3-pin (GP) connector
• large 6-pin connector (Molex)
• aluminum heatsink
• potentiometer of 20K if you want to add volume control

120W Power Amplifier PCB Layout Design

Bottom PCB Layout (Copper)

Top PCB Layout and Component Placement

How to mount the transistors to the aluminium heatsink, see below image:

The points are: prevent circuit shortage, use proper isolator and use thermal compound for maximum heat spreading to the heatsink. Use mica between the transistor and the heatsink.

Power Supply Circuit for 120W Power Amplifier

Power Supply Bottom PCB Layout

Power Supply Top PCB Design

Power Supply Part List

• Transformer for the mono amplifier should be 35 + 35 volts AC with a minimum of 3 amps. If the stereo channel, the amperage should be doubled.
• Capacitors of 4700 uF/63V: 4
• Diode bridge (rectifier) ​​of 15 Amps: 1

120W Power Amplifier Wiring Connection

This is how to connect the amplifier module to the speaker, power supply and audio input. And connect the power supply module to the transformer.

This 6V and 12V car battery charger circuit can be automatically charged, quickly and correctly, 6V and 12V batteries. Circuit design is divided into two series of modules that are: power supply module and the main charger module containing the regulator modules and direct current amplifier module.

How the 6V and 12V Car Battery Charger Works

A key factor in the success of the operation of the circuit is the use of good quality transformer [T1]  with very good insulation and resistance to short circuits. The Q1 through divider R1-2, of TR1 and R4, functions as a regulated current source. The current through R9 drives power transistors Q5-6, where amplified approximately x2000 times. In an unloaded car battery voltage is about 6V to 8V. With these conditions, the charge current is about 1.2A [regulated by TR1]. When the battery is charging slowly, gradually increases the voltage at its ends. 7V to enter into the D1 conducts. As the battery voltage increases, the voltage decreases at the ends of R3 Q1 made the most conductive. This continues until the current reaches about 6A. Then by means of the voltage drop across R10, is made conductive to Q4. The excess current to the base of Q5 to ground, keeping the load current constant. When the battery is fully charged [14.4V] activated in parallel to the circuit battery, consisting of R6, D8, D2 to D6. At the same time illuminates the D8 indicating that the battery has been fully charged. Simultaneously Q2 is conducting because the voltage drop on R6. The Q3 is conductive and grounded part of the stream at the base of Q5. When the voltage across the battery reaches approximately 15V current at the base of Q5 is very small, so to stop charging the battery. Diodes D5-6 protect the circuit from accidentally installing the battery or short circuits of long duration. The diode D4 protects the circuit from wrong positioning of the battery terminals. Then D9 Led lights showing connection error [ERROR]. Closing switch S2 short the diode D2 [6.8V], now we can charge 6V battery.

6V and 12V Car Battery Charger Component List

6V and 12V Car Battery Charger  Adjustment

The initial charge current should be adjusted via the TR1 to 1.2A. The adjustment can be done with a 6V battery. Connect in series with the battery a current [maximum 10A]. If there is 6V battery is short-circuited through the ammeter the charger terminals and adjust the TR1 current to 1.2A. When setting the switch S2 should be in the position of 12V, i.e. open. Particular attention should be paid to the accuracy of the diodes D2 and D3 because they protect the battery from overcharging. If the differential voltage is 100mV to go to consider them as acceptable. If you encounter difficulties in the current setting and the TR1 is not enough, you can change the value of the resistor R4, to measure charge current 1.2A. The two parallel resistors constituting R10, should be placed at a distance from the printed and Q5-6, because heated. The bridge B1 and Q5-6 be mounted on heatsink having insulated electrically from this with suitable mica silicone. The bridge B1 and the board in which the circuit is mounted must be connected with short and thick cables, especially where the current is large. lines are also printed on must have the appropriate width [in the project are shown in thicker line]. The construction should be done in a nice metal box, suitable dimensions so there is good ventilation. The construction requires the expertise.

WORK WITH BATTERIES REQUIRE HIGH ATTENTION IN HANDLING BECAUSE THERE IS ALWAYS A RISK OF EXPLOSION.

This is the circuit diagram of 5VDC single polarity to 12VDC dual polarity converter based on IC LM2595-12 from National Semiconductor. This circuit will convert 5V DC single voltage (+) become 12V DC dual polarity output (+), GND, (-).

Many electronic devices need a ?12V power supply. Typical examples include analog circuits or RS-232 driver power supplies. The ?12V typically needs to be generated from a 5V system bus. The solutions normally used involve a multiple secondary transformer or multiple switching regulators. These solutions can be complicated, may require custom transformer design and may have poor efficiency and poor regulation. The 5VDC single polarity to 12VDC dual polarity converter circuit shown in above image is simple, uses only one switching regulator IC, uses a small number of components, and provides good regulation at a high efficiency. Additionally, all the components used in this circuit are off the shelf components.

The converter circuit in above image uses an LM2595-12 (buck SIMPLE SWITCHER?) based switching regulator to generate both the +12V and the -12V outputs from 5V input. The LM2595 is configured as an inverting buck-boost converter to obtain the negative output. The positive output is generated using an additional winding in the off-the-self inductor (CTX250-4 from Coiltronics) used in this circuit. Only one additional diode (D3) and a capacitor (C3) are needed to generate the positive output.

This circuit come from Application Note #1118 by National Semiconductor about Simple Regulator Provides ?12V from 5V Source using LM2595-12.
Download the application note AN-1118:

AN-1118 - 5V to 12V DC Converter

1 file(s) 51.89 KB

Download

This is the circuit diagram of 0-60V / 0-2A variable power supply. Of course this circuit used to cover the voltage range from 0 to 60V and current from 0 to 2A. The maximum current can be increased, if we add the power transistors needed. Note the power output, just to cite one example, if delivery 2A 12V source to have a voltage drop of 48V with 2A consumption giving us a dissipation of 100 watts, is not a heating source, so, care.

Close attention should be paid to the way in which the two transistors BC327 circuit current protection, which work in saturation cutting work, another deals only activate an LED indicator on-load when the voltage drop lights output and will have to press the RESET button provided for the case. This will activate the output voltage again.

As already mentioned, this source has an intensity control, which disconnects the output voltage. This does not mean that supports the intersection of the (positive and negative) output cables. We must avoid this situation if possible as this will cause the destruction of transistors and other circuit components, it should be noted that we are dealing with respectable power.

For example: 5V and 2A output, this represents 65V – 5V = 60V which must be dissipated by the output transistors 2A, are talking about the power loss of 120 watts as a small “electric fire” this heat, more heat produced by 10W consumption advantage, they must evacuate 130W between the radiator and a fan that helps to lower the temperature that produces this “heater”, otherwise, you can imagine the result.

This is the circuit diagram of 3V to 9V DC converter which capable to deliver output voltage about 10.4v on no load and 9.6v @30mA. By using this circuit, You will be able to replace a 9v battery from 3V DC input.

The advantage is the voltage stays over 9v for the life of the cells, while a normal 9v battery drops to 7v very quickly.

The output voltage is set to 9-10v by the 6k8 and 390R resistors. The 470R gives the circuit an idling current of about 20mA and the spikes are about 75mV.

By increasing the 470R, the quiescent current decreases but the voltage drops more when the current is 30mA.

I hope this 3V to 9V DC converter circuit useful for you. Good luck.

Power transistors Q1 and Q2 are connected as series regulators to control the battery charger ‘s output voltage and charge-current rate. An LM-317 adjustable voltage regulator supplies the drive signal to the bases of power transistor Q1 and Q2.

Potensiometer R9 sets the output-voltage level. A current sampling resistor, R8 (a 0.1 ohm/5W unit), is connected between the negative output lead and circuit ground. For each amp of charging current that flows through R8, a 100mV output is developed across it. The voltage developed across R8 is fed to one input of comparator U3. The other input of the comparator is connected to variable resistor R10.

As the charging voltage across the battery begins to drop, the current through R8 decrease. Then the voltage feeding pin 5 of U3 decreases, and the comparator output follows, turning Q3 back off, which completes the signal’s circular path to regulate the battery’s charging current.

The charging current can be set by adjusting R10 for the desired current. The circuit’s output voltage is set by R9, adjust the R9 to get the correct voltage output value as needed.

This is the circuit diagram of USB power booster, expecially to strength the power capability of USB port from PC / laptop / notebook. USB from PC can supply only a limited power to the external devices connected through its USB port, when too many devices are connected simultaneously, there is a possibility of power shortage. Therefore an external power source has to be added to power the external devices.

In USB, two different types of connectors are used: type A and type B. The circuit presented here is an addon unit, designed to add more power to a USB supply line (type-A). When power signal from the PC (+5V) is received through socket A, LED1 glows, opto-diac IC1 conducts and TRIAC1 is triggered, resulting in availability of mains supply from the primary of transformer X1. Now transformer X1 delivers 12V at its secondary, which is rectified by a bridge rectifier comprising diodes D1 through D4 and filtered by capacitor C2.

Regulator IC 7805 is used to stabilise the rectified DC. Capacitor C3 at the output of the regulator bypasses the ripples present in the rectified DC output. LED1 indicates the status of the USB power booster circuit.

Construct the circuit on a general purpose PCB and mount in a suitable box. Bring out the +5V, ground and data points in the type-A socket. Connect the data cables as assigned in the circuit and the USB power booster is ready to use.

This is the circuit diagram of adjustable symmetric 1 to 24VDC, 1A Power Supply. This power supply give dual output positive and negatif output, you can adjust both positif and negative output (+1 to +24VDC and -1 to -24VDC). This kind of power supply also known as dual polarity power supply or splitted power supply which give positive anf negatif output.

This power supply can be used for universal usage, which required not more than 1A DC current. Please take a note that you should adjust the output voltage using general multimeter or DC voltmeter before use this power supply to protect the supplied devices.

Circuit Features:

• Low cost universal symmetric power supply
• Just add a suitable transformer and a heatsink
• Ideal for e.g. op-amp applications, amplifiers, …
• Trimmers can be replaced by potmeters to allow continuous adjustment of output voltage
• LED output indicators

Circuit Specifications:

• Positive and negative output adjustable between 1.2 and 24VDC
• Output current: up to 2 x 1A continuous (with suitable heatsink)
• Max. input voltage: 2 x 24VAC
• Very good line and load regulation
• Low ripple
• Short circuit protection
• Thermal protection

Circuit Manual of Adjustable Symmetric 1 to 24VDC, 1A Power Supply:

Adjustable Symmetrical Power Supply

1 file(s) 1.45 MB

Download Circuit Manual

Kit Version:
This circuit available in kit version by valleman, you may purchase this kit online.

Here is the schematic diagram of digital DC voltmeter built based IC ICL7107. The power supply for this circuit is +5V. You may use 9V battery and then use regulator IC LM7805 to achieve 5V stabilized voltage. This circuit will be good to display your power supply output.

Components List:

R1 = 8K2
R2 = 47K / 470K
R3 = 100K
R4 = 2K
R5, R6 = 47K
R7 = 0R / 4K7
R8 = 560R
C1,C5, C6, C8, C9 = 100n
C2 = 470n / 47n
C3 = 220n
C4 = 100p
C7 = 10-22u
D1, D2 = 1N4148
IC1 = ICL7107
IC2 = NE555
OPTO = CA 10 pin

Top PCB Layout:

Bottom PCB Layout:

Constructed Circuit:

This is the another DC voltmeter circuit design which show you about how to make reading scale. It is just need rotary switch and some resistors with different value at the input/measurement point.

source: http://www.reber.si/dvm/index.htm