NEDSP900 Development Board
2
Contents
1.0
Introduction
1.1
Recommendation
1.2
Board Mechanics
1.3
General Specifications
2.0
The inputs
2.1
SK6 Speaker/Headphone/Line Signals
2.2
SK7 Microphone Input Signals
2.2.2 Electret Bias
2.3
Balanced Input Pre=amplifiers
2.4
Signal Input Selection
2.5
Overload Indicators
3.0
Gain Settings
3.1
Setting the gain for SK7 (Microphone input)
4.0
Noise Reduction Settings
5.0
Outputs
5.1
Line Drive
5.2
Headphone/Speaker Output
6.0
Other Facilities on the Board
6.1
Audio Monitor Points
6.2
Noise Reduction Control
6.3
Algorithm ‘Hold’ (SF)
7.0
Connector Specifications
Appendix A – PCB Schematic Diagrams, Component Positions and BOM
Appendix B – Balanced Input Amplifiers
Appendix C – Fitting the board to an enclosure
