Maintenance of ALC3240 sound card

The sound card only outputs sound in the left channel, and there is no sound in the right channel, and the sound is too small to be heard clearly. I take apart the machine and want to make a transformation. I’ll replace it and eliminate it first.notebookThe sound of the built-in speaker removed from the computer is much better, but when I tried the machine, the connection was not wrapped with electric tape and it was bare. If I accidentally touched the battery voltage of 15V, the sound card chip burned a hole.

I bought a brand-new ALC3240 chip and installed it, but the computer can’t recognize the sound card chip. I used Lenovo driver management to detect the hardware information. There is a sound card ALC3240, but it can’t be installed because there is no sound device in the device manager.

Disassemble the machine, and test that 1-pin DVDD and 8-pin DVDD-IO have AUD_3VD, 16-pin VD33STB has AUD_3V3_S5, 34-pin PVDD1 and 39-pin PVDD2 have AUD_5VD, and 20-pin AVDD1 has AUD_5VA. AUD_5VD and AUD_5VA are renamed from 5V_S0. The grounding resistance of 4-pin SDATA-OUT, 5-pin BCLK, 7-pin SDATA-IN and 9-pin SYNC is more than 500, and the measured voltage of 4-pin and 9-pin is 0V, 5-pin 1V is more than 7-pin 2V, and the clock of 5-pin is 24M at the same time. The 40-pin PDB is connected to AUD_SD#, and the signal comes from AMP_MUTE# and HDA_CODEC_RST#, so it is a mute and reset pin, with a measured value of 3.3V.

All the above are normal, but the problem lies in AUD_1D8VD connected with 33-pin AVDD2 and 29-pin CPVDD, and the measured value is 0V.

AUD_1D8VD checkschematic diagramFrom 1D8V_S0, 1D8V_S0 is converted from 3D3V_S5 by PU5402(S-1339D18 screen printing Y5J), and inPoint bitmapI can’t find it on the computer. I ran the circuit on the motherboard and found it on the back of the sound card. The measured inputs 3D3V_S5 and PWR_1D8V_EN_AUDIO both have 3.3V, but the output is 0V. I bought it online and replaced it. Done.