HiFiBerry DIGI+ with Transformer

The digital sound board for Raspberry-Pi with a large bandwidth

This version of Digi+ includes the transformer module that you can identify right behind the coaxial connection (75 Ohms impedance). The Digi+ without transformer is available here.
This addition on the Digi+ offers you a galvanic isolation of the output. The use of this high quality Transformer module even makes it possible to achieve a bandwidth of 150 MHz. Even if the transformer introduces a slight jitter on the signal, its great advantage is to electrically isolate the audio signal from the power supply Pi... which is a real plus for audiophiles if we consider the average quality of the power of the Pi and its USB devices (the design is not sufficiently noise immune). 
However, this is an audiophile consideration. 

Back to the DiGi+

HiFiBerry Digi+ is a high quality S/PDIF audio output card for Raspberry-Pi 3, Pi 2 and A+/B+. It is designed as an additional card connected to the P1 and P5 section of the Raspberry-Pi GPIO (P1 and P5 are now included in the 40-pin GPIO).

At HiFiBerry, they like Raspberry-Pi, its small size, low consumption and flexibility. However, the sound produced by the card is not really good... the audio interface was not designed to produce high fidelity sound. HiFiBerry can add high-quality sound to your Raspberry-Pi. The HiFiBerry card is designed to produce optimal sound quality, so it is an optimal solution for all Pi users who love music. The card is compatible with Raspberry Pi 3, Pi 2, A+, B+ models (but not the old A and B models). The HiFiBerry are available in different models DAC+ (analog output), Digi+ (digital output) and Amp+ integrating an amplifier.     

HiFiBerry products plug directly into the GPIO port of the Raspberry-Pi. All cards are supported by the standard Raspbian kernels from the Raspberry-Pi distribution. HiFiBerry is committed to Open-Source software, so that all drivers are available in Open Source and HiFiBerry gladly supports developers who want to use the HiFiBerry in their software.  

HiFiBerry products are already assembled and there is no need to make welds to use the HiFiBerry card.  

For us hackers in electronics

HiFiBerry had the great idea to make a breakout of GPIO pins. So, even with the connector already welded, it remains possible to connect your sensors, cobbler, etc. Opt for a two-step weld, a first row of 20 PinHeader pins then the second row of 20 pins. Attempting to weld a dual-rank connector will be much more difficult.

You will also find a breakout of: 

• The 5V power supply - we advise you not to use it to avoid bringing "noise" on the power supply.  
• TOSLINK-RECEIVER signals - but we are unable to know if they are exploitable and supported by the HiFiBerry kernel module. See the HiFiBerry forum for more information.
• INPUT - just like the TOSLINK-RECEIVER signal, we are not able to evaluate the scope and interest of this signal. See the HiFiBerry forum for more information.
• The headphone Jack - even if the jack is not supplied and welded, you could easily place one on this emplacement. 

Contain

The fully assembled HiFiBerry card including the transformer module, and 4 M2.5 x 12mm spacers to fix the card to your Raspberry-Pi. This card is a version with optical output.
Raspberry-Pi not included.  

Technical details

• Hat for Raspberry-Pi A+, B+, Pi 2, Pi 3
• S/PDIF interface integrated circuit dedicated support up to 192KHz and 24 bit resolution.
• No modification of the digital audio stream (called "bit-perfect output")
• Optical (Toslink) and electrical outputs
  
• Directly powered by the PI.
  No need for additional power
• Ultra-low-noise regulator for optimal audio performances
• Integrated EEPROM for automated configuration (with write protection).
• The standard version of the Digi+ doesn't include galvanic isolation between the Raspberry-Pi and DAC on the electrical output.
• Weight: 20 gr
• Dimensions: 55 x 65 x 10 mm

Note d'HifiBerry

Although the hardware is capable of outputting Dolby Digital/DTS, the software must be adapted for supporting it. HiFiBerry will support the developers in their implementation. However, HiFiBerry can't guarantee that this feature will work with specific software... Check with the software developer if the feature is supported. See the HifiBerry.com product sheet.