11/19/2014

Programing UART in ARM Microcontrollers

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A UART is usually an individual (or part of an) integrated circuit used for serial communications over a computer or peripheral device serial port. UARTs are now commonly included in microcontrollers. A dual UART, or DUART, combines two UARTs into a single chip. An octal UART or OCTART combines eight UARTs into one package, an example being the NXP SCC2698. Many modern ICs now come with a UART that can also communicate synchronously; these devices are calledUSARTs (universal synchronous/asynchronous receiver/transmitter).

Programing UART in ARM Microcontrollers: you can find here: www.gadgetronicx.com

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Programming tutorial adc ARM Microcontrollers

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So, the microcontrollers today offering a more and simple solution our lives. One of the controllores is LPC11Cx2. The LPC11Cx2/Cx4 are an ARM Cortex-M0 based, low-cost 32-bit MCU family, designed  for 8/16-bit microcontroller applications, offering performance, low power, simple instruction set and memory addressing together with reduced code size compared to existing 8/16-bit architectures.The LPC11Cx2/Cx4 operate at CPU frequencies of up to 50 MHz. The peripheral complement of the LPC11Cx2/Cx4 includes 16/32 kB of flash memory, 8 kB of data memory, one C_CAN controller, one Fast-mode Plus I2C-bus interface, one RS-485/EIA-485 UART, two SPI interfaces with SSP features, four general purpose counter/timers, a 10-bit ADC, and up to 40 general purpose I/O pins.On-chip C_CAN drivers and flash In-System Programming tools via C_CAN are included. In addition, the LPC11C22 and LPC11C24 parts include an on-chip, high-speed CAN transceiver. 
Programming tutorial adc ARM Microcontrollers
Programming tutorial adc ARM Microcontrollers
One of intereting article you can find here www.gadgetronicx.com 
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11/15/2014

Arduino Uno Rev3 schematic

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Auto ranging ohmmeter using arduino

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This article is about a simple auto ranging ohmmeter using arduino. The measured resistance is displayed using a 16×2 LCD display. The circuit is sufficiently accurate and uses minimum number of external components possible. Before going into the details of this project, lets have a look at the basic resistance measurement method.

Resistance measurement.

Auto ranging ohmmeter using arduinoThe figure above shows the circuit diagram of a simple resistance measurement scheme. Rx is the resistance to be measured. R1 is the input resistance. i is the current passing through the loop and 5V is the supply voltage. To find the unknown resistance Rx, the voltage across Rx is measured first. let the voltage across R1 be VR1. Then VR1=5-Vx. The current i=VR1/R1=(5-Vx)/R1. Since R1 and Rx are connected in series, the current through them will be equal. So the unknown resistance Rx= Vx/i. The voltage across the unknown resistance is measured using the ADC of the arduino. To be precise, analog channel A5.

Anyway this method have a drawback. If there is great difference between the input resistance and the Rx, the result will be extremely inaccurate. This is because almost all of the input voltage will drop across the larger resistance and this provides very less information.
Suppose R1=10K and Rx=100 ohm. Then the voltage across R1 will be 4.95v and voltage across Rx will be 50mV and this gives less information. The sensitivity of the arduino is 4.889mV. So when we read 50mV using the arduino ADC the result will be 10. When converted it into voltage the result will be 10 x 4.889mV =48.89mV. Then Rx= 0.0488/((5V-48.89mV)/10000) = 98.7 ohm.
Suppose R1=10 and Rx=220 ohm. Then the voltage across R1 will be 4.89V and voltage across Rx will be 107mV. The corresponding digital reading will be 21. When we convert it into voltage the result will be 21 x 4.889mV=102mv. Following the calculations used in the previous case, Rx=208 ohm. In the above two cases you can see accuracy issues. The most accurate result occurs when the Rx and R1 are as close as possible.

Auto ranging.

A scheme for estimating the value of Rx roughly and then putting a matching resistor in place of R1 is what we need here and this method is called auto ranging. The circuit given below demonstrates auto ranging. 
Resistances R1 to R7 are the input resistors. In this scheme the free end of one resistor is held high and the free ends of other resistors are held low. The the voltage across the unknown resistance Rx is measured. Diodes D1 to D7 are used to prevent the back flow of current towards the low ends. Suppose free end of R1 is held low. If R1 and Rx are equal, then the voltage drop across Rx will be (5-0.7)/2 = 2.15 where 0.7 is the diode drop. If the voltage across Rx is less than or equal to 2.15, we can assume that Rx is less than or equal to 220 ohms. The closest value possible for the input resistance is 220 ohms and so this loop is considered for calculation. If the above condition is not satisfied, the above steps are repeated with the succeeding input resistors until we get a solution.
Circuit diagram.

Full circuit diagram of the auto ranging ohmmeter using arduino is shown in the figure above. Digital pins 1, 6, 7, 8, 9, 10, 13 of the arduino are used to switch the input resistors R1, R2, R3, R4, R5, R6, R7 respectively. Resistors D1 to D7 are used to prevent the back flow of current through the corresponding path. D8 is the power ON indicator LED. POT R10 is used for contrast adjustment of the LCD. Resistor R9 limits the back light LED current.

Program.
#include<LiquidCrystal.h>
int vin=A5;
int t=1;
int u=6;
int v=7;
int w=8;
int x=9;
int y=10;
int z=13;

int at;
int au;
int av;
int aw;
int ax;
int ay;
int az;
int a;
double vx;
float rx;
double i;
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
void setup()
{
pinMode(vin,INPUT);
lcd.begin(16,2);

pinMode(t,OUTPUT);
pinMode(u,OUTPUT);
pinMode(v,OUTPUT);
pinMode(w,OUTPUT);
pinMode(x,OUTPUT);
pinMode(y,OUTPUT);
pinMode(z,OUTPUT);

digitalWrite(t,LOW);
digitalWrite(u,LOW);
digitalWrite(v,LOW);
digitalWrite(w,LOW);
digitalWrite(x,LOW);
digitalWrite(y,LOW);
digitalWrite(z,LOW);
}
void loop()
{

digitalWrite(t,HIGH);
digitalWrite(u,LOW);
digitalWrite(v,LOW);
digitalWrite(w,LOW);
digitalWrite(x,LOW);
digitalWrite(y,LOW);
digitalWrite(z,LOW);
delay(100);
at=analogRead(vin);




digitalWrite(t,LOW);
digitalWrite(u,HIGH);
digitalWrite(v,LOW);
digitalWrite(w,LOW);
digitalWrite(x,LOW);
digitalWrite(y,LOW);
digitalWrite(z,LOW);
delay(100);
au=analogRead(vin);
digitalWrite(t,LOW);
digitalWrite(u,LOW);
digitalWrite(v,HIGH);
digitalWrite(w,LOW);
digitalWrite(x,LOW);
digitalWrite(y,LOW);
digitalWrite(z,LOW);
delay(100);
av=analogRead(vin);



digitalWrite(t,LOW);
digitalWrite(u,LOW);
digitalWrite(v,LOW);
digitalWrite(w,HIGH);
digitalWrite(x,LOW);
digitalWrite(y,LOW);
digitalWrite(z,LOW);
delay(100);
aw=analogRead(vin);


digitalWrite(t,LOW);
digitalWrite(u,LOW);
digitalWrite(v,LOW);
digitalWrite(w,LOW);
digitalWrite(x,HIGH);
digitalWrite(y,LOW);
digitalWrite(z,LOW);
delay(100);
ax=analogRead(vin);


digitalWrite(t,LOW);
digitalWrite(u,LOW);
digitalWrite(v,LOW);
digitalWrite(w,LOW);
digitalWrite(x,LOW);
digitalWrite(y,HIGH);
digitalWrite(z,LOW);
delay(100);
ay=analogRead(vin);



digitalWrite(t,LOW);
digitalWrite(u,LOW);
digitalWrite(v,LOW);
digitalWrite(w,LOW);
digitalWrite(x,LOW);
digitalWrite(y,LOW);
digitalWrite(z,HIGH);
delay(100);
az=analogRead(vin);

if(az>=450)
{
vx=az*0.00489;
i=(5-vx-0.55)/22000;
rx=(vx/i);
}
if(ay>=450 && az<450)
{
vx=ay*0.00489;
i=(5-vx-0.55)/10000;
rx=(vx/i);
}
if(ax>=448 && ay<448 && az<448)
{
vx=ax*0.00489;
i=(5-vx-0.55)/4700;
rx=(vx/i);
}

if(aw>=439 && ax<439 && ay<439 && az<439)
{
vx=aw*0.00489;
i=(5-vx-0.55)/2200;
rx=(vx/i);
}

if(av>=439 && aw<439 && ax<439 && ay<439 && az<439)
{
vx=av*0.00489;
i=(4.8-vx-0.55)/1000;
rx=(vx/i);
}

if(au>=430 && av<430 && aw<430 && ax<430 && ay<430 && az<430)
{
vx=au*0.00489;
i=(4.5-vx-0.55)/560;
rx=(vx/i);
}

if(at>=430 && au<430 && av<430 && aw<430 && ax<430 && ay<430 && az<430 )
{
vx=at*0.00489;
i=(4.5-vx-0.55)/220;
rx=(vx/i);
}

if(at<430 && au<430 && av<430 && aw<430 && ax<430 && ay<430 && az<430 )
{
vx=at*0.00489;
i=(4.5-vx-0.55)/220;
rx=(vx/i);
}
lcd.setCursor(0,0);

if(vx>4.8)
{
lcd.clear();
lcd.setCursor(0,0);
lcd.print("----INFINITY----");
}
else
{
if(rx<1000)
{
lcd.clear();
lcd.setCursor(0,0);
lcd.print(rx);
lcd.setCursor(7,0);
lcd.print((char)244);
}
else
{
lcd.clear();
rx=rx/1000;
lcd.setCursor(0,0);
lcd.print(rx);
lcd.setCursor(6,0);
lcd.print("k");
lcd.print((char)244);
}
}
lcd.setCursor(0,1);
lcd.print("Arduino Ohmmeter");
}

sourse: www.circuitstoday.com
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11/14/2014

Dual Audio Power Amplifier 6 W × 2 Ch

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TA8246AH is dual power amplifier for Consumer applications. This IC provides an output power of 6 watts per channel (at VCC = 20 V, f = 1 kHz, THD = 10%, RL = 8 Ω). It is suitable for power amplifier of TV and home Stereo. 
Circuit diagram:
Dual Audio Power Amplifier 6 W × 2 Ch
Dual Audio Power Amplifier 6 W × 2 Ch



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22W x 4 Channel Audio Amplifier Circuit Diagram TA8255AH

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22W x 4 Channel Audio Amplifier Circuit Diagram TA8255AH
22W x 4 Channel Audio Amplifier Circuit Diagram TA8255AH

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30 watt 4 Channel audio amplifier IC

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Circuit diagram for TA8251AH:
30 watt 4 Channel audio amplifier IC
30 watt 4 Channel audio amplifier IC

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6mW 1.5V Stereo Headphone Amplifier

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The TA8159FN developed for play−back stereo headphone  equipments (1.5V use). It is built in dual auto−reverse pre  amplifiers, dual OCL power ampilfiers, and a ripple filter. 

Circuit Diagram:
Circuit diagram for 6mW 1.5V Stereo Headphone Amplifier
Circuit diagram for 6mW 1.5V Stereo Headphone Amplifier 



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7.3W x 2CH audio amplifier ic

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7.3W x 2CH audio amplifier ic
7.3W x 2CH audio amplifier ic

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30 Watt x 2 CH AUDIO POWER AMPLIFER

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TA8233H Circuit Diagram
30 Watt x 2 CH AUDIO POWER AMPLIFER
Circuit diagram for 30 Watt x 2 CH AUDIO POWER AMPLIFER

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Dual pre power amplifier , dc volume control

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Dual pre power amplifier dc volume control
Dual pre power amplifier dc volume control

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5W mono audio amplifier

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The TDA7056B is a mono Bridge-Tied Load (BTL) output amplifier with DC volume control. It is designed for use in TV and monitors, but is also suitable for battery-fed portable recorders and radios. The device is contained in a 9-pin medium power package.

Circuit Diagram:
5W mono audio amplifier
5W mono audio amplifier

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Dual 6 to 8 watt audio power amplifier

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The HA1394 dual audio power amplifier is specifically designed for audio outputs in modular stereos and mutiplex sound TV's. This HItachi amplifier can deliveri 8.2w per ch when Vcc=25V.

Circuit Diagram:
Dual 6 to 8 watt audio power amplifier
Dual 6 to 8 watt audio power amplifier


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11/13/2014

2.5W Audio Power Amplifier

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Description:
The LM380 is a power audio amplifier for consumer applications. In order to hold system cost to a minimum, gain is internally fixed at 34 dB. A unique input stage allows ground referenced input signals. The output automatically selfcenters to one-half the supply voltage.
Circuit diagram:
2.5W Audio Power Amplifier
2.5W Audio Power Amplifier

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4 x 11 W or 2 x 22 W power amplifier

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General Description:
The TDA1554Q is an integrated class-B output amplifier in a 17-lead single-in-line (SIL) plastic power package.The circuit contains 4 x 11 W single-ended or 2 x 22 W bridge amplifiers. The device is primarily developed for car radio applications.
Circuit Diagram:
circuit diagram 2 x 22 W audio power amplifier
circuit diagram 2 x 22 W audio power amplifier

circuit diagram 4 x 11 W audio power amplifier
circuit diagram 4 x 11 W audio power amplifier
Datasheet for TDA1554Q: Download
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11/11/2014

Dual Audio Power Amplifier

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General Description:
The TA8211AH is dual audio power amplifier for consumer applications.  This IC provides an output power of 6 watts per channel  (at VCC = 20 V, f = 1 kHz, THD = 10%, RL = 8 Ω). 
It is suitable for power amplifier of TV and home stereo. 

Features:
  • High output power: Pout = 6 W/channel (Typ.) 
  •  (VCC = 20 V, RL = 8 Ω, f = 1 kHz, THD = 10%) 
  • Low noise: Vno = 0.14 mVrms (Typ.) 
  •  (VCC = 28 V, RL = 8 Ω, GV = 34dB, Rg = 10 kΩ, 
  •  BW = 20 Hz~20 kHz) 
  • Very few external parts 
  • Built in thermal shut down protector circuit 
  • Operating supply voltage range: VCC (opr) = 10~30 V (Ta = 25°C) 

Circuit Diagram:
Dual Audio Power Amplifier
Circuit diagram for Dual Audio Power Amplifier 

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24 W BTL or 2 x 12 W stereo car radio power amplifier

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General Description:
The TDA1515BQ is a monolithic integrated class-B output amplifier in a 13-lead single in-line (SIL) plastic power package. The device is primarily developed for car radio applications, and also to drive low-impedance loads (down to 1,6 Ω). At a supply voltage VP = 14,4 V, an output power of 24 W can be delivered into a 4 Ω BTL (Bridge Tied Load), or, when used as stereo amplifier, it delivers 2 × 12 W into 2 Ω or 2 × 7 W into 4 Ω. 

Features:
  • flexibility in use − mono BTL as well as stereo
  • high output power
  • low offset voltage at the output (important for BTL)
  • large usable gain variation
  • very good ripple rejection
  • internal limited bandwidth for high frequencies
  • low stand-by current possibility (typ. 1 µA), to simplify required switches; TTL drive possible
  • low number and small sized external components
  • high reliability.
  • he following currently required protections are incorporated in the circuit. These protections also have positive influence
  • on reliability in the applications.
  • load dump protection
  • a.c. and d.c. short-circuit safe to ground up to VP = 18 V
  • thermal protection
  • speaker protection in bridge configuration
  • SOAR protection
  • outputs short-circuit safe to ground in BTL
  • reverse polarity safe.
Circuit Diagram:
24 W BTL or 2 x 12 W stereo car radio power amplifier
Circuit diagram for 24 W BTL or 2 x 12 W stereo car radio power amplifier
Datasheet for TDA1515BQ
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Audio Power Amplifier 5.8W

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General Description:

The NTE1285 and NTE1286 are audio power amplifiers in a 7–Lead SIP type package designed especially for car radio and car stereo applications. These devices are encapsulated in newly developed small packages featuring low thermal resistance, providing easy design for 2Ω. At 14.4V the devices give output power of 7W with RL = 4Ω and 11W with RL = 2Ω.

Features:

High Output Power
Low Transient Noise at Power Supplu Switch ON
Mirror Image Pin Configurations
Protection Circuits are Provided for the Following:
Load Dump Protection
Thermal Shut–Down Protection
Overvoltage Protection
Output Terminal Short–Circuit Protection

Pinout:
Pin diagram Audio Power Amplifier 5.8W
Audio Power Amplifier 5.8W

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11/10/2014

60 W Quad Half-Bridge Digital Amplifier

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General Description:
The CS44130 is a high-efficiency power stage for digital Class-D amplifiers designed to recieve PWM signals from a modulator such as the CS44800/600. The power stage outputs can be configured as four half-bridge channels, two half-bridge channels and one full-bridge channel, two full-bridge channels, or one parallel full-bridge channel.
Features:
 Configurable Outputs (10% THD+N)
– 2 x 30 W into 8 Ω, Full-Bridge
– 1 x 60 W into 4 Ω, Parallel Full-Bridge
– 4 x 15 W into 4 Ω, Half-Bridge
– 2 x 15 W into 4 Ω, Half-Bridge + 1 x 30 W 
into 8 Ω, Full-Bridge
 Space-Efficient, Thermally-Enhanced QFN 
Package
 PWM Popguard® Technology for Quiet Startup
 > 100 dB Dynamic Range - System Level
 < 0.12% THD+N @ 1 W - System Level
 Built-In Protection with Error Reporting
– Over-Current
– Thermal Warning
– Thermal Fault
– Under-Voltage
 Single (+10.8 V to +21 V) High Voltage Supply
 High Efficiency (90%)
 Low RDS(ON)
 Low Quiescent Current
 Low Power Standby Mode
Common Applications
 Digital Televisions
 MP3 Docking Stations
 Mini Shelf Systems
 Networked Audio/POE Systems
 Desktop Speakers

Circuit Diagram:
60 W Quad Half-Bridge Digital Amplifier
60 W Quad Half-Bridge Digital Amplifier
Datasheet for CS44130: Download
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11/06/2014

43 W BTL × 4-ch Audio Power IC

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Overview:
The TB2904H (o) is 4-ch BTL audio amplifier for car audio applications.  This IC can generate higher power: POUT MAX = 43 W as it includes the pure complementary P-ch and N-ch DMOS output stage. It is designed to yield low distortion ratio for 4-ch BTL audio power amplifier, built-in standby function, muting function, and various kinds of protectors. 

Circuit Diagram:
Circuit diagram for  43 W BTL × 4-ch Audio Power IC
Circuit diagram for  43 W BTL × 4-ch Audio Power IC
Datasheet for TB2904H: Download
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47 Watt 4-channel Audio Power Circuit Diagram

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Overview:
TB2903HQ

The TB2903HQ is 4-ch BTL audio amplifier for car audio applications. This IC can generate higher power: POUT MAX = 47 W as it includes the pure complementary P-ch and N-ch DMOS output stage. It is designed to yield low distortion ratio for 4-ch BTL audio power amplifier, built-in standby function, muting function, and various kinds of protectors. Additionally, Off-set detector is built in. 
Features 
  • High power output 
  • POUT MAX (1) = 47 W (typ.) 
  • VCC = 14.4 V, f = 1 kHz, JEITA max, RL = 4 Ω) 
  • Built-in standby switch function (pin 4) 
  • Built-in muting function (pin 22) 
  • Built-in Off-set detection function (pin 25) 
  • Thermal shut down, overvoltage, out to GND, out to VCC, out to out short 
  • Operating supply voltage: VCC (opr) = 9~18 V (RL = 4 Ω) 
Circuit Diagam:
47 Watt 4-channel Audio Power Circuit Diagram
47 Watt 4-channel Audio Power Circuit Diagram
Datasheet for  TB2903HQ: Download

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11/04/2014

18W+18W Stereo Amplifier

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General Description:

The TDA7265SA is class AB Dual Audio Power amplifier assembled in the @ Clipwatt 11 package, specially designed for high quality sound application as Hi-Fi music centers and stereo TV sets. The TDA7265SA is pin to pin compatible with TDA7269, TDA7269A, TDA7269SA, TDA7265,TDA7499, TDA7499SA. 

Circiut Diagram:
18W+18W Stereo Amplifier
18W+18W Stereo Amplifier

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5.4W Dual Audio Power Amplifier

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General Description:
The BA5415A and BA5416 are dual power amplifier ICs that operate off a 9V to 15V supply. When driving a 4Ω load off a 9V supply, the BA5415A does not require a heatsink. The BA5416 uses a lost-cost package. The basic characteristics (total harmonic distortion etc.) of the amplifiers are excellent, and both ICs include a standby switch function.
Features

  • High output.
  • POUT = 5.4W (VCC = 12V, RL = 3Ω and THD = 10%)
  • POUT = 2.5W (VCC = 9V, RL = 4Ω and THD = 10%)
  • Excellent audio quality.
  • THD = 0.1% (f = 1kHz, PO = 0.5W)
  • VNO = 0.3mVrms (Rg = 10kΩ)
  • RR = 60dB (fRR = 100Hz)
  • Wide operating power supply voltage range.
  • VCC = 5.0V to 18.0V (BA5416 : 5.0V to 15.0V)
  • Switching noise (ìpopî noise) generated when the power is switched on and off is small.
  • Ripple mixing when motor starts has been prevented.
  • Built-in thermal shutout.
  • Built-in standby switch.
  • Output is not influenced by the standby pin voltage.
  • Mute time does not depend on VCC.
  • Soft clipping.
  • Heatsink not required  (for BA5415A, with VCC = 9V and RL ≥ 4Ω).

Circuit Diagram:
5.4W Dual Audio Power Amplifier
5.4W Dual Audio Power Amplifier
Datasheet for BA5415A: Download
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11/03/2014

1W Per Channel Stereo Class-D Audio Power Amplifier

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Features
  • 1 watt per channel with 8-ohm load
  • Max. efficiency » 80% with 8-ohm load at 5 volts
  • Filterless
  • Digital gain control
  • Build-in depop circuitry
  • Error protection for short circuit and over-temperature
  • Mute (shutdown) current < 1µA typical
  • Low operating current (4mA at 5 volts without load)
  • TSSOP 24L package available 

General Description
The AP130 is an oversampling class-D power amplifier for  stereo audio applications. It provides high power-efficiency for filterless 8-ohm load. Build-in depop, mute and gain control features simplify the applications. BTL (Bridge-Tied-Load) configuration delivers up to 1 watt into 8-ohm load per channel at 5-V supply voltage. It allows direct coupling of the power signal. Reliability is
improved through over-temperature and short circuit protections. The class-D power amplifier enables high efficiency applications for portable devices.

Circuit Diagram
1W Per Channel Stereo Class-D Audio Power Amplifier
1W Per Channel Stereo Class-D Audio Power Amplifier


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70W x 1ch BTL Power Amplifier

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Circuit diagram for AN17850A:
70W x 1ch BTL Power Amplifier
70W x 1ch BTL Power Amplifier

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Audio power amplifier IC

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Dual 6.5 power audio amplifier.
Audio power amplifier IC
Audio power amplifier IC

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Audio signal processing 1 W × 2-channel

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Overview:
AN12942B is an one-chip IC for the stereo speakers which can output 1 W by 8 Ω, headphone amplifiers, line amplifiers, and electronic volumes. The AGC circuit is built-in to prevent the resonance or the vibration by the speaker’s energy and the clipping distortion what is  called "broken up sound".  Also the AN12942B is built-in power saving on/off function automatically detecting input signal to save the power of speaker  amplifier.

Circuit Diagram:
Audio signal processing
Audio signal processing

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11/02/2014

Audio power IC for mp3 Player

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Overview:
The AN12941A is an amplifier IC for stereo  speakers which can output 1 W by 8 Ω or 2 W by 4 Ω. The AGC circuit is built-in to prevent the resonance  or the vibration by the speaker's energy and the  clipping distortion what is called "broken up sound."  of the speakers. Also, to reduce power consumption, AN12941A  has a built-in function which automatically detects the  input signal and can automatically enter power save  mode when there is no signal.
Features:
  • Speaker amplifier is
  • 1 W × 2-channel: 8 Ω, VCC = 5 V or
  • 2 W × 2-channel: 4 Ω, VCC = 5 V
  • Built-in AGC circuit
  •  Prevention of the resonance or the vibration by 
  • the speaker's energy and the clipping distortion 
  • of the speaker by AGC at excessive input signal 
  • (with AGC on/off switch).
  • Built-in automatic power saving function
  •  It detects input signals and switches on/off (with 
  • the on/off switch for the automatic power saving).
  • Operating supply voltage: VCC 3.0 V to 5.5 V/ 
  • VCC_SP 3.0 V to 5.5 V
Circuit Diagram:
Audio power IC for mp3 Player
Audio power IC for mp3 Player

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Auto Radio Amplifier Circuit

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„ Features

  • Dual 10 W audio power amplifier
  • Built-in muting circuit
  • Incorporating protection circuit
  • Low frequency amplifier
  • SIL-12 pin plastic package (Power-type with fin)
Circuit Diagram:
Auto Radio Amplifier Circuit
Auto Radio Amplifier Circuit


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Stereo 50W Audio Power Amplifier

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FEATURES DESCRIPTION
The LM4732 is a stereo audio amplifier capable of 2 typically delivering 50W per channel of
continuous The LM4732 has short circuit protection and a APPLICATIONS thermal shut down feature that is activated when the  The LM4732 also has an under voltage lock out feature for click and Each amplifier of the LM4732 has an independent KEY SPECIFICATIONS The LM4732 has a wide operating supply range from +/-10V - +/-40V allowing for lower cost unregulated power supplies to be used.

Features:

• Mute Attenuation 110dB (typ)
• PSRR 89dB (typ)
• Slew Rate 19V/μs (typ)
• Low External Component Count
• Quiet Fade-in/out Mute Mode average output power into a 4Ω or 8Ω load with less
• Wide Supply Range: 20V - 80V than 10% THD+N from 20Hz - 20kHz.
• Audio Amplifier for Component Stereo die temperature exceeds 150°C.
• Audio Amplifier for Self-powered Speakers
• Output Power/Channel at 10% THD+N, 1kHz 
• Audio Amplifier for Compact Stereo pop free power on and off.
• Audio Amplifier for High-end and HD TVs smooth transition fade-in/out mute.
• THD+N at 2 x 1W into 8Ω, 1kHz 0.01% (typ) bridge or parallel operation for 100W mono solutions.

Circuit Diagram:
Stereo 50W Audio Power Amplifier
Stereo 50W Audio Power Amplifier 

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Three Channel Audio Mixer

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General Description:
Above schematic is for a three channel audio mixer. That will provide an overall gain of one between the output and each input channel. Each input channel includes a single 0.1uf capacitor and 100-Kilohms resistor to provide an output impedance of 100K. The number of input channels to this audio mixer can be increased by adding more capacitors and resistors with same value as capacitor(0.1uf) and resistor(100K). The mixer should be located between the output of tone control circuitry and the input to the power amplifier. One input should be taken from the output of the tone control circuit, and the other inputs should either be grounded or taken from desired source.
Circuit diagram:
Three Channel Audio Mixer circuit diagram
Three Channel Audio Mixer circuit diagram


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Audio Mixer

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General Description:
A new audio mixer circuit uses an LM3900 IC but is not a profesional audio dj mixer. The IC houses four integrated Norton amplifiers. The advantage of using the four op amps is that they only need a single power supply. Since this amplifier circuit is current controlled, the DC bias is dependent on the feedback coupling.The schematic diagram shows inverting AC-Norton amplifiers. The DC output must be set at 50 percent of the power supply. In this case, a maximum output can be achieved without distortion (also called symmetrical limitation through overdrive).In designing this mini audio mixer circuit diagram you can freely choose the value of the resistor R2 (100k in the mixer schematic). Set the AC voltage amplification factor through the ration of R2/R1. To set the amplifier gain correctly, choose the value of R4=2R2 (double the value of R2).Diagram 1.0 shows the 3-channel sound mixer circuit using three Norton-opamps. The input levels can be set by potentiometers P1 or P3. Furthermore, each input level can be trimmed with the help of trimmers pots P4 to P6 to adapt each input to the source. The resistors at the non-inverting inputs of the opamps work as DC bias and set the DC output at 50 percent of the power supply for this powered audio mixer. All three input signals are summed by the fourth opamp A4 through the resistors R3, R7 and R11. The commom volume level is cotrolled through the potentiometer P7. You can switch an input channel on or off through the switches S1 and S3. An input channel is turned off when its switch is closed. It is also possible to replace these mechanical switches with transistor gates. By doing so, you can build an analog multiplexer circuit that can be easily expanded by several inputs.
Circuit Diagram and PCB:
Audio Mixer Circuit Diagam
Audio Mixer Circuit Diagam

Audio Mixer Circuit Diagam
Audio Mixer Circuit digram

Audio Mixer Circuit Diagam
Audio Mixer layout

PCB Audio Mixer
PCB Audio Mixer





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