The DAC module is based on the multi-level delta-sigma Asahi Kasei Microdevices AK4490 IC in a "dual mono" mode. Each channel uses a separate independent DAC IC together with antialiasing filters and power supplies. The synthesis of control signals, the interface module synchronization signal, the preliminary processing and the data stream separation are carried out in a high-speed 4th generation CPLD. To increase noise immunity, all control, data and synchronization lines are equipped with receiving buffer elements. The DAC module digital functional notes are powered by individual integral regulators, with individual LC filters for each group of logic elements.
The Apollo DAC is powered by a classic linear PSU with three customized power transformers for separate servicing various DAC modules. Each power transformer is specially designed and fabricated in-house with minimal magnetic induction in the core which results in extremely low level external magnetic field, small value and peak factor of the idle current, negligible vibration and low loss and interference.
The Apollo’s display is deliberately simple with an elegance derived from this simplicity with the readings being short and intuitively understandable. Engineered to the smallest detail all control and display processes have no microcontrollers or clocks.
The combination of the unique properties of transformers with effective shielding and protection allowed to refuse completely pointless and only high cost the product of two or more structure-options.
Transmission line of the clock signal at IC DAC is made in the form of a closed microstrip line harmonized in the structure of the multilayer printed circuit Board. This allows you to virtually eliminate the influence of external noise on the clock signal and to bring to the tact converters with jitter less than 50 - 60 femtoseconds.
All Apollo modules are precision multi-layer printed circuit boards made of vibration absorbing foiled material with uniform dielectric permittivity over the surface and enhanced 70 μm copper foil tracks. The PCBs are covered with an antistatic mask, all the vias and pads are immersion gold plated.
Maximum shielding from outside interference