Isolator for Amanero USB I2S with reclock

It is recommended to use the board with USB modules  converted to "slave" mode  (receiving a clock signal from the DAC board). 

At the same time, the board allows the use of amanero in master mode, but for this you should use another isolator (for example, ADUM1400CRW), the relevance and expediency of using a reclock in this case is sharply reduced.

Printed circuit board

The device is made on a 42x78mm double-sided printed circuit board. Below is a 3D view of the PCB with components

Adapter circuit with reclock

D-triggers can be replaced with the new AUP series - 74AUP1G79. 

The "USB power option" part of the circuit is unsoldered only if you are going to use power from the USB port. When using this option from the amanero board, just like in the case of external power, remove the standard LDO for 3.3v and apply 5V power from the USB connector to the "USB + 5v" pin. 

The design has been tested over a year with various DACs and has shown good results. The most noticeable results when using reclock were obtained with TI - PCM179x chips. 

For chips from AKM, there is a very small gain in sound  at low sampling rates compared to a conventional adapter without reclocking.    

When using the 22.5792 / 24.576 MHz clock generators used in the Amanero, the maximum sampling rate when using the reclock is capped at 192 kHz. 

Unfortunately, this limitation does not allow us to recommend this board as the main option for the AH-D6x line.