GM29 INTEGRATOR’S MANUAL
Audio signal descriptions are listed below:
Pin | Signal | Dir | Description |
|
|
|
|
1 | MICN | I | Microphone negative input |
|
|
|
|
2 | BEARN | O | Earpiece negative output |
|
|
|
|
3 | BEARP | O | Earpiece positive output |
|
|
|
|
4 | MICP | I | Microphone positive input |
|
|
|
|
MICP and MICN are balanced differential microphone input signals. These inputs are compatible with an electret microphone.
BEARP and BEARN are the speaker output signals. These are
Parameter | Limit |
|
|
Output level (differential) | ≥4.0Vpp |
Output level (dynamic load = 32Ω) | ≥2.8Vpp |
|
|
Distortion at 1kHz and maximum output level | ≤5% |
|
|
Offset, BEARP to BEARN | ±30mV |
|
|
≥40dB | |
|
|
The following table shows the ear piece impedances that can be connected to BEARP and BEARN.
Ear piece model | Impedance | Tolerance |
|
|
|
Dynamic ear piece | [32Ω + 800µH] // 100pF | ±20% |
|
|
|
Dynamic ear piece | [150Ω + 800µH] // 100pF | ±20% |
|
|
|
Piezo ear piece | 1kΩ + 60nF | ±20% |
|
|
|
30
LZT 123 7361 R1A
