BHI NEDSP1901-PCB User Manual page 7

2.5 Electrical Characteristics
Output impedance: 1k Ohms typical
Input impedance: 7.5k Ohms typical
Parameter
Vin
Iin
In
Out
Parameter
VHigh
VLow
3.0 Installation
The NEDSP1901 module is inserted into the path of the noisy audio. Adjusting the Input and Output
level controls allows the module to appear transparent to the audio signal level.
Figure5. General Audio signal flow with 1901 module installed
The NEDSP1901 requires a minimum signal level of 10mV rms or greater for optimum performance.
Signals lower than this may be used but the noise cancellation performance will be degraded as the
signal level drops. If the module is to be used with low level microphones, the signal will require
pre-amplification. The Output level control may be used to attenuate the signal back down to the
original signal level.
Analogue Characteristics
Description
Supply Voltage
Supply Current
Audio Input Signal
Audio Output Signal
Digital Characteristics
Description
High Level Input Voltage
Low level Input Voltage
Min. Typ.
5 8
15
10 500
Min. Typ.
- 3.3
0.8 -
Max. Units
15 V
20 mA
mV (rms)
1000
Max. Units
5 V
- V