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This is what I have done so far  CALCULATIONS. R_L=8 Ω P_AVG=10W Bandwidth from 20 Hz to 18 kHz V_(0 peak)=√(2×10×8)=12.65v

V_CC=V_(0 peak)×2+2=27.3V≅28V I_(0 peak)=V_(0 peak)/R_L =12.65/8=1.58A Each transistor current is given by: I_(0 peak)/2=1.58/2=0.79A Assuming β=113 I_(B Q1)=I_(B Q2)=I_E/(β+1)=0.79/114=6.93mA Assuming I_D=1A Then: I_bias=1mA+1mA+6.93mA+6.93mA=15.86mA Setting V_C=14V Then R4=(28V-14v-0.7v-0.7V)/15.86mA=794.5Ω

Setting V_E=1V R_3+R_3^II=1V/15.86mA=63.05Ω Input current is assumed to be 500mA Q_3 gain is given by V_(O peak rms)/V_(in rms) = √(8×10)/500mA=17.88Ω

Setting Q_3 gain to 20: R_3^II=((28V-14V)/15.86mA)/20=44.14Ω R_3=63.05-44.14=18.92Ω I_B=I_C/β=15.86mA/100=0.1586mA Setting I_1=20 I_B I_B=20×0.1586mA=3.172mA R_2=1.7V/3.172mA=535Ω R_1=(28V-1.7V)/3.172mA=8291Ω Designing for C_1 and C_3

r_e=26mV/15.86mA=1. 64Ω R_1 ||R_2=502.57Ω R_3^II=44.14Ω R_th=41.96Ω C1=C3=1/(2×π×f_L×R_th )=1/(2×π×20×44.14)=189.65μF

Designing for C_2

R_th=69.6759Ω C_2=10/(2×π×f_L×R_th )=10/(2×π×20×69.6759)=1142μF

When I simulate,output voltage is quite small and the output power is much less than 10W.What could be the issue?  The final circuit I came up with is shown.

This is what I have done so far 

CALCULATIONS.

• R_L = 8 Ω

• P_AVG = 10W

• Bandwidth from 20 Hz to 18 kHz

• V_(0 peak) = √(2×10×8) = 12.65v

• V_CC = V_(0 peak)×2+2 = 27.3V ≅ 28V

• I_(0 peak) = V_(0 peak)/R_L = 12.65/8 = 1.58A

Each transistor current is given by:

• I_(0 peak)/2 = 1.58/2 = 0.79A

Assuming β = 113

• I_(B Q1) = I_(B Q2) = I_E/(β+1) = 0.79/114 = 6.93mA

Assuming I_D = 1A, then:

• I_bias = 1mA+1mA+6.93mA+6.93mA = 15.86mA

Setting V_C = 14V, then:

• R4 = (28V-14v-0.7v-0.7V)/15.86mA = 794.5Ω

Setting V_E = 1V

• R_3+R_3^II = 1V/15.86mA = 63.05Ω

Input current is assumed to be 500mA Q_3 gain is given by:

• V_(O peak rms)/V_(in rms) = √(8×10)/500mA = 17.88Ω

Setting Q_3 gain to 20:

• R_3^II = ((28V-14V)/15.86mA)/20=44.14Ω
• R_3=63.05-44.14 = 18.92Ω
• I_B = I_C/β = 15.86mA/100 = 0.1586mA

Setting I_1 = 20 I_B:

• I_B = 20×0.1586mA = 3.172mA
• R_2 = 1.7V/3.172mA = 535Ω
• R_1 = (28V-1.7V)/3.172mA = 8291Ω

Designing for C_1 and C_3:

• r_e = 26mV/15.86mA = 1.64Ω
• R_1 ||R_2 = 502.57Ω
• R_3^II = 44.14Ω
• R_th = 41.96Ω
• C1 = C3= 1/(2×π×f_L×R_th) = 1/(2×π×20×44.14) = 189.65μF

Designing for C_2:

• R_th = 69.6759Ω
• C_2 = 10/(2×π×f_L×R_th) = 10/(2×π×20×69.6759) = 1142μF

When I simulate the circuit, the output voltage is quite small and the output power is much less than 10W.

What could be the issue? 

The final circuit I came up with is shown.

I am required to design a class AB audio amplifier to deliver 10W to an 8Ω speaker as shown, but I don't know where to start. The bandwidth is to cover the range from 20Hz to 18kHz. Input voltage is 500mV rms.

Could anyone guide me please?

_{Image source: Electronics Tutorials - Class AB Amplifier Driver Stage}

I got Vo peak as √(10 * 8 * 2) which gives 12.65V. I then set Vcc=Vo peak*2 +1 which gives 27V. How do I get the current and resistor values? Load current Io peak = 12.65/8 = 1.58A

I am required to design a class AB audio amplifier to deliver 10W to an 8Ω speaker as shown, but I don't know where to start. The bandwidth is to cover the range from 20Hz to 18kHz. Input voltage is 500mV rms.

_{Image source: Electronics Tutorials - Class AB Amplifier Driver Stage}

This is what I have done so far CALCULATIONS. R_L=8 Ω P_AVG=10W Bandwidth from 20 Hz to 18 kHz V_(0 peak)=√(2×10×8)=12.65v

V_CC=V_(0 peak)×2+2=27.3V≅28V I_(0 peak)=V_(0 peak)/R_L =12.65/8=1.58A Each transistor current is given by: I_(0 peak)/2=1.58/2=0.79A Assuming β=113 I_(B Q1)=I_(B Q2)=I_E/(β+1)=0.79/114=6.93mA Assuming I_D=1A Then: I_bias=1mA+1mA+6.93mA+6.93mA=15.86mA Setting V_C=14V Then R4=(28V-14v-0.7v-0.7V)/15.86mA=794.5Ω

Setting V_E=1V R_3+R_3^II=1V/15.86mA=63.05Ω Input current is assumed to be 500mA Q_3 gain is given by V_(O peak rms)/V_(in rms) = √(8×10)/500mA=17.88Ω

Setting Q_3 gain to 20: R_3^II=((28V-14V)/15.86mA)/20=44.14Ω R_3=63.05-44.14=18.92Ω I_B=I_C/β=15.86mA/100=0.1586mA Setting I_1=20 I_B I_B=20×0.1586mA=3.172mA R_2=1.7V/3.172mA=535Ω R_1=(28V-1.7V)/3.172mA=8291Ω Designing for C_1 and C_3

r_e=26mV/15.86mA=1. 64Ω R_1 ||R_2=502.57Ω R_3^II=44.14Ω R_th=41.96Ω C1=C3=1/(2×π×f_L×R_th )=1/(2×π×20×44.14)=189.65μF

Designing for C_2

R_th=69.6759Ω C_2=10/(2×π×f_L×R_th )=10/(2×π×20×69.6759)=1142μF

When I simulate,output voltage is quite small and the output power is much less than 10W.What could be the issue? The final circuit I came up with is shown.

I am required to design a class AB audio amplifier to deliver 10W to an 8Ω speaker as shown, but I don't know where to start. The bandwidth is to cover the range from 20Hz to 18kHz. Input voltage is 500mV rms.

Could anyone guide me please?

_{Image source: Electronics Tutorials - Class AB Amplifier Driver Stage}

I got Vo peak as √(10 * 8 * 2) which gives 12.65V. I then set Vcc=Vo peak*2 +1 which gives 27V. How do I get the current and resistor values?

I am required to design a class AB audio amplifier to deliver 10W to an 8Ω speaker as shown, but I don't know where to start. The bandwidth is to cover the range from 20Hz to 18kHz. Input voltage is 500mV rms.

Could anyone guide me please?

_{Image source: Electronics Tutorials - Class AB Amplifier Driver Stage}

I got Vo peak as √(10 * 8 * 2) which gives 12.65V. I then set Vcc=Vo peak*2 +1 which gives 27V. How do I get the current and resistor values? Load current Io peak = 12.65/8 = 1.58A