An approx. 10 Watt mono class D bass guitar amplifier for driving an 8-ohm speaker. The power amp is based on a TPA3125 chip. A 12-volt power supply capable of delivering at least 1 amp (preferably more) is required. Use a decent quality power supply. I found the cheap power supplies to be too noisy.

Cost: approx. $40 per completed board
Board: approx. $42 for (3) boards
Parts: approx. $26 per board

Status: see video here; use at your own risk

Bill of Material:
U1 - Audio Op-amp, p/n: LM833NGOS-ND
U2 - 10V, 100mA Regulator, p/n: 296-1996-ND
U3 - TPA3125 Class D Amplifier, p/n: 296-24090-5-ND

Q1 - MOSFET, n-Channel, 200mA, p/n: 2N7000TACT-ND

L1, L2 - 22uH, 4A Inductor, p/n: AIUR-06-220K-ND

C1, C2, C3, C4, C6, C21, C28 - 10uF, 50V Aluminum Cap, p/n: 493-11003-1-ND
C5 - 100uF, 16V Aluminum Cap, p/n:493-4638-1-ND
C7, C27 - 100pF, 50V Ceramic Cap, p/n:445-4726-ND
C8, C10, C11, C14, C15, C22 - 1uF, 16V Ceramic Cap, p/n:445-8614-ND
C9, C16, C17, C18, C19, C20 - 0.22uF, 50V Ceramic Cap, p/n:445-8625-ND
C12, C13 - 470uF, 35V Aluminum Cap, p/n:P14942-ND
C23, C24 - 1000pF, 50V Ceramic Cap, p/n:445-5246-ND
C25, C26 - 10000pF, 50V Ceramic Cap, p/n:445-4750-ND

R1, R2 - 1Meg, 1/4W Resistor, p/n: 1.00MXBK-ND
R3, R4 - 2.21k, 1/4W Resistor, p/n: 2.21KXBK-ND
R5 - 1k, 1/4W Resistor, p/n:1.00KXBK-ND
R6 - 22.1k, 1/4W Resistor, p/n: 22.1KXBK-ND
R7, R8, R9, R16 - 47.2k, 1/4W Resistor, p/n: 47.5KXBK-ND
R10, R11 - 10k, 1/4W Resistor, p/n: 10.0KXBK-ND
R12 - 10k Potentiometer, p/n: CT6EP103-ND
R13 - 100k Potentiometer, p/n: PTV09A-4225F-B104-ND
R14, R15 - 3.3 Ohm, 1/4W Resistor, p/n: 3.3QBK-ND

J1, J2, J3 - 2 Pos Terminal Blk, p/n: ED1643-ND

Misc:
Knob, p/n: 450-1742-ND
¼" Jack, p/n: SC1316-ND
12V Power Supply, p/n: 285-1884-ND

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