Audio DAC S / PDIF (AES3) to analog


Posted on May 28, 2012

The described device is used to convert the digital signal format S / PDIF (AES3) to analog. It can be used for any device with uncompressed digital audio output (desktop CD or DVD, minidisk, sound card PC CD-ROM). Separate transmitter can improve the signal to noise ratio and reduce noise, which is especially true for the PC sound card. The device does not signal processor, and therefore not able to play back compressed or encoded multichannel signal (AC3, MP3, respectively. Mpeg)!


Audio DAC S / PDIF (AES3) to analog
Click here to download the full size of the above Circuit.

The converter has been tested only for signals with a sampling frequency of 32 kHz (minidisc), 44.1 kHz (CD) and 48 kHz (sound card PC). For lower frequencies need to be adjusted PLL loop filter, the higher divider circuit to add two, see text. Involvement of the transmitter to the receiver S / PDIF is the figure 1 . Digital input signal passes through C1 at the receiver input. Differential input receiver and the outlets RXP Rxn. The receiver is able to process signals from a few tens of millivolts for units of volts. Disconnect the jumper, J1, we can connect the input signal in TTL level, such as output from a CD-ROM or from the optical receiver. In hardware mode, the circuit is switched to the outlet level H 24th Resistors R5 and R7 is set circuit function. Logic level on pin 3, 18 and 28 are read after a reset circuit, before they switched to the output pins. The receiver is a phase coupling (PLL), which is required for proper function of the receiver and decoder. Output phase-Fitr hinge pin is connected to the eighth Voltage on this pin controls the internal oscillator (VCO). The voltage on this pin can therefore be assumed on the sampling frequency of the received signal. Another way to determine the sampling rate (if it were necessary), to measure frequency oscillator on pin 10 (RMCK). In developing the first version of the converter I used in the filter PLL component values ??from the datasheet (Crip = C3 = = 2.2...




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

McCAD PCB software
Triangular Wave Generator Using Op-amp
build relay toggle switch
speedometer project
ADUC841 20MIPS 8052 Flash MCU + 8-Ch 12-Bit ADC + Dual 12-Bit DAC
Attaching a GPS module to the EB675001DIP
ADA4858-3 used as a PIN diode driver circuit



Top