L1543 DAC four parallel TDA1543 fever USB decoder | Электроника

L1543 DAC four parallel TDA1543 fever USB decoder | Электроника

Five major circuit features:

USB direct power supply via CLC network, making the power supply pure
Four TDA1543 decoder chips are connected in parallel.
Accurately calculated working point, exclusive design of TDA1543 Vref fine adjustment resistor! If the TDA1543 is to be perfect, the resistance of the output resistance must be calculated accurately. The most important thing is that the Vref resistance must be accurate to ensure that the static voltage of the output resistance is at the midpoint of the output voltage swing. I believe you understand what this means.
Perfect wiring, digital and analog multi-level decoupling, strict distinction.
For a large number of fever components, please see the physical map and component list.

Key points for installation and commissioning:

The decoding and debugging is simple. After welding, insert the computer USB port and drive to recognize.
Two 300-ohm resistors are used for the output resistors in the kit. We will give you 8 when fitting. Please use a multimeter to filter out the 2 resistors as much as possible. This can ensure that the output voltage of the left and right channels is as consistent as possible.
Adjust the 2K adjustable resistor (Vref) so that the voltage of Aor and Aol is 2.8V. The USB voltage of many computers is less than 5V, then the final set voltage of Aor and Aol is calculated by this formula: 1.8+(VDD-1.8-1.2)/ 2. Among them, VDD is the measured USB output voltage. In short, the principle is to set Aor and Aol as the midpoint of the output voltage vibration amplitude! Finally, note that the voltage is the voltage to ground, that is, the black test pen can be connected to the USB socket shell or the RCA shell.
Due to the high current consumption of this decoder (about 300mA), please try to use the USB port with strong power supply at the back of the chassis. It is better to have a USB3.0 port. If necessary, you can use 2 parallel lines for power supply

The sound quality of this decoder must not be referenced by price. Her dynamics, resolution, and signal-to-noise ratio may subvert your perception of cost performance. The sound is soft and audible, the taste is full, the signal-to-noise ratio is very BT, and then the Lehman amp is used. With the PX200, the maximum volume cannot be heard with low noise!