Class D Amplifier

Class D Amplifier

Class D amplifier Class D amplifier circuit BD5460 Class D amplifier is a type of amplifier where the power devices (MOSFET ... 05:57:00

Class D amplifier

Class D amplifier circuit BD5460

Class D amplifier is a type of amplifier where the power devices (MOSFET or transistor) are operated as switches. There will be only two states (ON/OFF) for these switches and no time is wasted for the transition from one stage to another. The working of a class D amplifier is as follows. At first the audio signal to be amplified compared with a high frequency triangle waveform and the result will be a square wave whose duty cycle is proportional to the input audio level. This square wave is then fed to the gate of the switching element (MOSFET) for power amplification. The then the audio signal is retrieved from the amplifier square wave using an LC filter. The LC filter filters off the high frequency switching components from the square wave the amplified audio signal will be available at its output. The main advantage of class D amplifier are high efficiency (up to 95%), smaller size (small heatsinks are required for the switching element because of the low power wastage) , low cost (due to the smaller heatsinks and transformers).

BD5460 class D amplifier IC.

BD5460 is a low power Class D amplifier that can be used in low power applications like handheld audio devices. BD5460 does not require an LC filter at the speaker output and can be driven using a battery, The standby current of BA5460 is typically zero and there is no switch ON / OFF clicks. The BD5460 can deliver 0.8 watts into an 8 ohm speaker at 3.6 V supply voltage. The power supply voltage range is from 2.5 to 6.5 V DC. The IC has a built-in standby function, short circuit protection, thermal shutdown and under voltage lockout.

Description.

Two class D amplifier circuits using BD5460 are shown below. The first one is a differential input class D amplifier while the second one is a single ended input class D amplifier. The 0.1uF capacitors (C1, C2, C3 and C4) are input DC decoupling capacitors. The lower cut off frequency of the amplifier depends on these capacitors. 10uF capacitors (C5 and C6) are the power supply filters. S1 and S2 are the shutdown switches. Connecting the C1 pin to the high logic will make the IC active and connecting the C1 pin to ground will put the Ic into shutdown mode.

• The power supply voltage can be between 2.5 to 6.5V DC.
• For the circuit shown here, the supply voltage must be 3.6 V DC.
• Powering the circuit from a battery is the better option because it reduces noise.
• If you are using a DC power supply, then it must be well regulated and filtered.
• Audio inputs have to be connected with respect to the ground.

19w power amplifier circuit

19w power amplifier circuit

19w bridge amp circuit by la4440 Components required IC1 LA4440 c1--10uf,16v c2--220uf,16v c3--2A222J c4--220uf,16v c5--... 05:15:00

19w bridge amp circuit by la4440

Components required

• IC1 LA4440
• c1--10uf,16v
• c2--220uf,16v
• c3--2A222J
• c4--220uf,16v
• c5--220uf,16v
• c6--220uf,16v
• c7--220uf,16v
• c8--2A104J
• c9--2A104J
• c10--2200uf,25v
• R1--100ohm
• R2--56ohm
• R3--10k
• R4--100ohm
• R5--1ohm
• R6--1ohm

Let's start with basic

Let's start with basic

Resistor Color coding The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band resistors only. All 5-band ... 01:12:00

Resistor Color coding

The colors brown, red, green, blue, and violet are used as tolerance codes on 5-band resistors only. All 5-band resistors use a colored tolerance band. The blank (20%) “band” is only used with the “4-band” code (3 colored bands + a blank “band”).

The value of the resistor is marked on the body using colors. Every color is different number and you can remember these numbers or you can just use the table on next step. OR there are much resistor calculators that you can use. It's for the laziest people :D .  However it's your decision ,and I will show you all ways to calculate resistor value.

Colors

Here is the table with the colors and numbers. As you can see they are:

• BLACK:     0
• BROWN:   1
• RED:           2
• ORANGE:   3
• YELLOW:   4
• GREEN:       5
• BLUE:          6
• VIOLET:      7
• GREY:          8
• WHITE:        9

But this is not for all colors. From right to left the second color is multiplier. Digits from the first colors must be multiplied with the number of this color.

• BLACK:     1
• BROWN:   10
• RED:           100
• ORANGE:   1000
• YELLOW:   10000
• GREEN:       100000
• BLUE:          1000000
• GOLD:          0.1
• SILVER:       0.01

And the last color: This is tolerance. Tolerance is the precision of the resistor and it is given as a percentage. For example a 390 resistor with a tolerance of ±10% will have a value within 10% of 390, between 390 - 39 = 351 and 390 + 39 = 429 (39 is 10% of 390).

• BROWN:   1%
• RED:           2%
• GOLD:        5%
• SILVER:     10%
• NOTHING:  20%

Calculator

Resistor color code calculator
If you are too lazy to think about colors and digits and mat ... this is for you :) :D

Examples

Exemple: If first color is RED ,second is RED ,third is BLACK and the last is SILVER it means:
RED - 2  --  RED - 2  --  YELLOW - x10000  --  SILVER - 10%          so...
2   2   0000 +/- 10% * 2 2 0000   so... :D
220000 +/- 22000
This is 220 000 Ohm or 220 kOhm
or 220 000 - 22 000 Ohm or 220 - 22 kOhm
or 220 000 + 22 000 Ohm or 220 + 22 kOhm

Hope you got it :)