Philips 237E4QSD/93 Service Manual page 67

3.17.7 Maximum Audio Card Output
The monitor audio amplifier shall accept a maximum input voltage of 1.5 Vrms and meet
the following requirements at the maximum monitor volume setting:
1. The ratings of the audio amplifier may not be exceeded.
2. The ratings of the speakers may not be exceeded.
3. There must not be any clipping of the audio amplifier output signal.
Voltage dividers may be used to reduce the input signal level.
3.17.8 Monitor Audio Amplifier Input Impedance
The monitor audio amplifier shall have minimum 10K Ohm AC input impedance
UNCTIONAL Requirements for the front detection
For the presence sensor functionality, the following requirements are defined:

Two IRs be used for user present detections, one IR is for transmission signals, the other one is
for receiving reflection IR signals
 User must be detected in the following range:
40 up to 100 cm (+ 20cm).
 Detection angle:
+- 35 degree (for IR LED )
 SENSOR key control,
Adjust detection distances (0~4 scales), default is 3 , tolerance : (±10cm)
0 : 0FF
1 : 90 cm
2 : 100 cm
3 : 110 cm
4 : >130 cm
Power sensor
(option)
Meridian 3
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