AirPrime Module Datasheet
Table Of Contents
- 1: Introduction
- 2: Physical Characteristics
- 3: Audio Circuit
- 4: Hardware Design Guidelines
- 5: Power Supply Sequencing
- 6: GPIO Electrical Specifications
- 7: Solder Reflow Profile
- A: Regulatory Certifications
- B: Packaging Dimensions
Product Technical Specification
Rev 1 Apr.17 22 41110693
An example USB supply configuration is shown Figure 4-6:
Figure 4-6: Example USB Supply Configuration
The BC127/BC127-HD/BC127-EXT Discovery Board and the BC127/BC127-HD/
BC127-EXT Development Board use an external amplifier for audio application
demonstration purposes. For superior audio performance always follow the
design and layout guidelines provided by the amplifier manufacturer.
Always use a high quality audio amplifier ideally with click and pop suppression
circuits built in. These amplifiers use noise suppression and soft start techniques
to filter supply noise and transients as well as minimising ground loop currents
and DC offsets that can cause degraded audio effects. Some amplifiers even
employ ground sensing and suppression techniques to minimise and remove
noise coupling to the audio path.
In the example amplifier circuit below, the amplifier audio ground is connected to
the main ground via a single “star” point at the audio output jack. This is suitable
for connection to headphones where noise from an external source is not
expected. This circuit is used on the BC127/BC127-HD/BC127-EXT Development
Board.
Figure 4-7: Example External Audio Amplifier Connection Suitable for Connecting to External
Headphones