Wednesday, November 19, 2014
3W Stereo Amplifier schematic
| 3 Watt stereo amplifier circuit |
Thursday, November 6, 2014
Simple 50W Hi Fi amplifier with TDA7294
50W Hi-Fi amplifier Circuit Diagram
A symmetrical 30V power supply is all its need to power the unit.
Battery powered Headphone Amplifier
An improved output driving capability is gained by making this a push-pull Class-B arrangement. Output power can reach 100mW RMS into a 16 Ohm load at 6V supply with low standing and mean current consumption, allowing long battery duration. The single voltage gain stage allows the easy implementation of a shunt-feedback circuitry giving excellent frequency stability.
Battery-powered Headphone Amplifier Circuit Diagram:
- For a Stereo version of this circuit, all parts must be doubled except P1, SW1, J2 and B1.
- Before setting quiescent current rotate the volume control P1 to the minimum, Trimmer R6 to maximum resistance and Trimmer R3 to about the middle of its travel.
- Connect a suitable headphone set or, better, a 33 Ohm 1/2W resistor to the amplifier output.
- Switch on the supply and measure the battery voltage with a Multimeter set to about 10Vdc fsd.
- Connect the Multimeter across the positive end of C4 and the negative ground.
- Rotate R3 in order to read on the Multimeter display exactly half of the battery voltage previously measured.
- Switch off the supply, disconnect the Multimeter and reconnect it, set to measure about 10mA fsd, in series to the positive supply of the amplifier.
- Switch on the supply and rotate R6 slowly until a reading of about 3mA is displayed.
- Check again the voltage at the positive end of C4 and readjust R3 if necessary.
- Wait about 15 minutes, watch if the current is varying and readjust if necessary.
- Those lucky enough to reach an oscilloscope and a 1KHz sine wave generator, can drive the amplifier to the maximum output power and adjust R3 in order to obtain a symmetrical clipping of the sine wave displayed.
Output power (1KHz sinewave):
16 Ohm: 100mW RMS
32 Ohm: 60mW RMS
64 Ohm: 35mW RMS
100 Ohm: 22.5mW RMS
300 Ohm: 8.5mW RMS
Sensitivity:
160mV input for 1V RMS output into 32 Ohm load (31mW)
200mV input for 1.27V RMS output into 32 Ohm load (50mW)
Frequency response @ 1V RMS:
flat from 45Hz to 20KHz, -1dB @ 35Hz, -2dB @ 24Hz
Total harmonic distortion into 16 Ohm load @ 1KHz:
1V RMS (62mW) 0.015% 1.27V RMS (onset of clipping, 100mW) 0.04%
Total harmonic distortion into 16 Ohm load @ 10KHz:
1V RMS (62mW) 0.05% 1.27V RMS (onset of clipping, 100mW) 0.1%
Unconditionally stable on capacitive loads
Wednesday, November 5, 2014
Circuit Guards Amplifier Outputs Against Overvoltage
Circuit Diagram :
Figure 1 : This output circuit provides continuose protection against overvoltge faults
During normal operation, the amplifier outputs’ dc components are at one-half of the VCC supply—2.5V in this case, for which VCC is 5V. The 11V gate drive fully enhances the MOSFETs, and the shunt-regulator output is off because its feedback input, Pin 5, is below its internal 0.6V threshold. If either output exceeds 5V, current flows through D3 into the R5/R6 divider, pulling the feedback terminal above its threshold. The shunt-regulator output then pulls the MOSFET-gate voltage from 11V almost to ground, which blocks high voltage from the amplifier by turning off the MOSFETs. The MOSFETs easily withstand the continuous output voltage, and the circuit returns to normal operation when you remove the short. Because the circuit does not respond instantaneously, zener diodes D1 and D2 provide protection at the beginning of a fault condition.
The waveforms of Figure 2 represent an operating circuit. One of the amplifier’s outputs (Trace 1) is a 1-kHz sine wave biased at a dc voltage of 2.5V. Trace 2 is the signal on the wire harness. It also starts as a 1-kHz sine wave biased at a 2.5V-dc voltage, but, at 200 µsec, it shorts to an 18V supply. Trace 3 is the shunt regulator’s output, initially biased at 11V but pulled to ground in response to the overvoltage condition. Trace 4 is current in the wire harness. Initially a sine wave, this current drops to zero in response to the overvoltage condition.
The components in Figure 1 optimize this circuit for 5V operation. For other voltages, you can adjust the R5/R6 resistor values. The shunt regulator must be able to function in saturation and, therefore, requires a separate supply pin in addition to the shunt output pin. The circuit repeatedly withstands 28V shorts without damage.
2W Amplifier
The amplifier(s) can be conveniently supplied by a 12V wall plug-in adapter.Closing SW1 a bass-boost is provided but, at the same time, volume control must be increased to compensate for power loss at higher frequencies.
P1----------10K
R1----------33K
R2----------33K
R3----------33R
R4----------15K
R5----------1K
R6----------1K
R7----------680R
R8----------120R-1/2W
R9----------100R-1/2W Trimmer Cermet
C1 ----------10µF-63V
C2 ----------10µF-63V
C3-----------100µF-25V
C4-----------470µF-25V
C5-----------47pF-63V
C7-----------470µF-25V
C6-----------220nF-63V
C8-----------1000µF-25V
D1-----------1N4148
Q1-----------BC560C
Q2-----------BC337
Q3-----------TIP31A
Q4-----------TIP32A
SW1---------SPST switch
SPKR--------3-5 Watt Loudspeaker
Thursday, October 30, 2014
Dayton Amplifier SA1000
- Accessing back amplifier and found four clear plastic binding posts on rear panel.
- Strip 1/2 inch outer insulation of the cable end from the speaker to the subwoofer amplifier. Play a piece of wire tightly on each conductor.
- Remove the lower knurled button at the bottom of the banana plug. This shows the hole in the center of the plug body.
- Slide the speaker wire into the hole on a banana plug. Match the red wire to the red line on a banana plug. Repeat for the black wire and black striped banana plug.
- Slide the red wire into the hole below the end of the set of binding posts marked with a red strip. Repeat for the black wire.
Tuesday, October 28, 2014
Audio Distribution Amplifier
| Audio Distribution Amplifier |
Monday, October 27, 2014
BA5406 10W Stereo Power Amplifier
| BA5406 10 Watt Stereo Power Amplifier |
Sunday, October 26, 2014
LM1875 80W audio power amplifier Diagram Circuit
A very simple high efficiency 80W audio power amplifier project can be designed using the LM3875 power audio IC . LM3875 is a high-performance audio power amplifier capable of delivering 56W of continuous average power to an 8Ω load with 0.1% THD+N from 20Hz to 20kHz .
By connecting two LM39875 audio IC in bridge mode this audio power amplifier will deliver 80 watt of output power into an 8 Ohm load. The LM3875 IC devices should be suitably heatsinked.
As you can see in the circuit diagram , this power audio amplifier require few external electronic parts .
The LM3875 maintains an excellent signal-to-noise ratio of greater than 95dB(min) with a typical low noise floor of 2.0μV.
This 80W audio power amplifier module accepts a wide range input voltage from 20 up to 84 volts, but typically is recommended ( for this circuit ) a dual +/-25 volts DC power supply .
Some features of this 80W audio power amplifier project based on the LM1875 IC are :
output protection from a short to ground or to the supplies via internal current limiting circuitry ,output over-voltage protection against transients from inductive loads ,supply under-voltage protection .
Thursday, October 16, 2014
50W Electronic Amplifier Rise
With the addition of a handful of parts and an appropriate power supply, this module will deliver over 50W RMS in to four or 8 ohms-with < 0.1% Total Harmonic Distortion (THD) and < 0.1% Inter-modulation Distortion (IMD). It is also suitable as a replacement power amp stage, or upgrade for plenty of existing amplifiers of between 30W-50W, provided they have an appropriate dual supply, & most do.
D.C. Input : 35V
Output power : > 50W RMS, 4-8 ohm load.
Gain : 24 dB (30dB modification)
Input sensitivity : one.3V for 50W, 8 ohm
Signal-to-Noise ratio : > 95 dB, (>105 dBA)
Frequency response : approx. 20Hz - 200kHz, �3 dB
Slew rate : > 10V/uS
THD : < 0.01%, 1W-40W, 1kHz
IMD : < 0.01%, 1W
A 36V C.T. transformer will give you approx +/- 25V rails. The-mains transformer used ought to be rated at a maximum of 80VA. In the event you require to run modules in a stereo amplifier you can use a common power supply. In this case the transformer ought to be rated at 150VA or greater.
Pin ten is a mute input and pin 9 provides a standby mode. Muting ought to always happen before standby mode is selected. Connecting these pins permanently to the supply rail ensures that the amplifier comes on immediately on power up. Any switch-on clicks may be eliminated by increasing the time constants of R5/C4 and R6/C5 if necessary.
Make definite that a heavy duty heat-sink rated at least one.4 degree C/W or better is used.
Sunday, September 21, 2014
Mini Guitar Bass Amplifier
Output power: 6W into 4 Ohm load, FET input stage – Passive Tone Control
Tiny, portable Guitar Amplifiers are useful for practice on the go and in bedroom/living room environment. Usually, they can be battery powered and feature a headphone output. This project is formed by an FET input circuitry, featuring a High/Low sensitivity switch, followed by a passive Tone Control circuit suitable to Guitar or Bass. After the Volume control, a 6W IC power amplifier follows, powered by a 12-14V dc external supply Adaptor or from batteries, and driving a 4 Ohm 10 or 13cm (4″/5″) diameter car loudspeaker. Private listening by means of headphones is also possible.
Circuit diagram:
Parts:
P1______________1M Linear Potentiometer
P2____________100K Log Potentiometer
R1_____________68K 1/4W Resistor
R2____________470K 1/4W Resistor
R3______________2K7 1/4W Resistor
R4______________8K2 1/4W Resistor
R5____________680R 1/4W Resistor
R6____________220K 1/4W Resistor
R7_____________39R 1/4W Resistor
R8______________2R2 1/4W Resistor
R9____________220R 1/4W Resistor
R10_____________1R 1/4W Resistor
R11___________100R 1/2W Resistor
R12_____________1K5 1/4W Resistor
C1____________100pF 63V Polystyrene or Ceramic Capacitor
C2,C5,C9,C14__100nF 63V Polyester Capacitors
C3____________100µF 25V Electrolytic Capacitor
C4_____________47µF 25V Electrolytic Capacitor
C6______________4n7 63V Polyester Capacitor
C7____________470pF 63V Polystyrene or Ceramic Capacitor
C8______________2µ2 25V Electrolytic Capacitor
C10___________470µF 25V Electrolytic Capacitor
C11____________22nF 63V Polyester Capacitor
C12__________2200µF 25V Electrolytic Capacitor
C13__________1000µF 25V Electrolytic Capacitor
D1______________3mm red LED
Q1____________BF245 or 2N3819 General-purpose N-Channel FET
IC1_________TDA2003 10W Car Radio Audio Amplifier IC
SW1,SW2________SPST toggle or slide Switches
J1____________6.3mm Mono Jack socket
J2____________6.3mm Stereo Jack socket (switched)
J3_____________Mini DC Power Socket
SPKR__________4 Ohm Car Loudspeaker 100 or 130mm diameter
| Elektor 303 Circuit |
| Practical Arduino |
| Elektor05-2010 |
| Elektor05-2010 |
| Elektor05-2010 |
| Nuts Volts 06-2010 |
| Nuts Volts 06-2010 |
source: http://electronicsprojects.mediadir.in/mini-guitarbass-amplifier/
Notes:
- Connect the output Plug of a 12 – 14V dc 500mA Power Supply Adaptor to J3
- Please note that if the voltage supply will exceed 18V dc the IC will shut down automatically
Technical data:
Output power (1KHz sinewave):
6W RMS into 4 Ohm at 14.4V supply
Sensitivity:
50mV RMS input for full output
Frequency response:
25Hz to 20kHz -3dB with the cursor of P1 in center position
Total harmonic distortion:
0.05 – 4.5W RMS: 0.15% 6W RMS: 10%
Tone Control Frequency Response:
1000W Power Amplifier
Circuit Description 1000W Power Amplifier:
Circuit Diagram 1000W Power Amplifier:
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| 1000W Power Amplifier |
Partlist 1000W Power Amplifier:


Sunday, September 14, 2014
2 x 32W DUAL BRIDGE CAR RADIO AMPLIFIER TDA7393
- HIGH OUTPUT POWER CAPABILITY:
- 2 x 35W max./4Ω
- 2 x 32W EIAJ/4Ω
- 2 x 22W typ./4Ω @ 14.4V, 1KHz, 10%
- 2 x 19W typ./4Ω @ 13.2V, 1KHz, 10%
- 2 x 28W typ./2Ω @ 14.4V, 1KHz, 10%
- 2 x 25W typ./2Ω @ 13.2V, 1KHz, 10%
- LOW DISTORTION
- LOW OUTPUT NOISE
- ST-BY FUNCTION
- MUTE FUNCTION
- AUTO-MUTE AT MIN. SUPPLY VOLTAGE
- DETECTION
- LOW EXTERNAL COMPONENT COUNT
- – INTERNALLY FIXED GAIN (32dB)
- – NO EXTERNAL COMPENSATION
- – NO BOOTSTRAP CAPACITORS
- ADDITIONAL MONO INPUT
- OUTPUT AC/DC SHORT CIRCUIT TO GND
- AND TO VS
- VERY INDUCTIVE LOADS
- OVERRATING CHIP TEMPERATURE WITH
- SOFT THERMAL LIMITER
Circuit Diagram:
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| 2 x 32W DUAL BRIDGE CAR RADIO AMPLIFIER |
Saturday, September 13, 2014
1000W Power Amplifier
Friday, September 12, 2014
Subwoofer Amplifier Circuit 60W

Thursday, September 11, 2014
Low Power Wireless Audio Power Amplifier
Transmitter diagram:
| Wireless Audio Power Amplifier Transmitter Circuit Diagram |
Receivers operation:
Receiver diagram:
| Wireless Audio Power Amplifier Transmitter Circuit Diagram |
Parts:
Stereo Headphone Amplifier
Component Stereo Headphone Amplifier
P1 = 22K
R1 = 18K
R2 = 68K
R3 = 68K
R4 = 68K
R5 = 18K
R6 = 68K
C1 = 4.7uF/25v
C2 = 4.7uF/25v
C3 = 22pF
C4 = 220uF/25v
C5 = 220uF/25v
C6 = 4.7uF/25v
C7 = 22pF
C8 = 220uF/25v
J1 = 3.5mm Stereo Jack
B1 = 9V Alkaline Battery
IC1 = NE5532 or NE5534
SW1 = SPST Toggle Switch
BUZ23 MOSFET Audio Amplifier 1 x 240W
BUZ23 MOSFET general description:
BUZ23 MOSFET circuit diagram:

Wednesday, September 10, 2014
powerful pocket Headphone Amplifier circuit Wiring diagram
Lots of guys asked me about Pocket head phone amplifiers.This schema will be a good answer for that.Here I have used very common IC OPA134.You can power this schema with 9V battery.
Note
# Design this schema on a PCB
# use 9V to power this schema
SOUND 2W MONO AMPLIFIER TDA7299
- CAN DELIVER 2W THD 10% 12V/8Ω
- INTERNAL FIXED GAIN 20dB
- NO BOUCHEROT CELL
- THERMAL PROTECTION
- AC SHORT CIRCUIT PROTECTION
- SVR CAPACITOR FOR BETTER RIPPLEREJECTION
- LOW TURN-ON/OFF POP
- STAND-BY MODE
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| Circuit diagram for SOUND 2W MONO AMPLIFIER |


