Panasonic KX-HCM110A Service Manual page 53

and the JPEG processing is performed here. The compressed encode
data are stored to the SDRAM. (2)
- A header is added to the encoded JPEG data by a direction of the CPU
and it is transferred to a network after a protocol processing. (3)
13.4. SOUND BLOCK
External Microphone Jack (CN603)
Used with the external microphone.
Speaker Jack (CN604)
Used when connecting a speaker with a built-in amplifier, when the sound is output from a camera.
Microphone Detection (Q603)
When the external microphone plug is not inserted, pins 3 and 2 of the Microphone Jack (CN603) are
short-circuited and a base current is supplied to Q603 through R603, R632 and R629 so that the Q603
goes ON and a collector (MIC_S signal) goes LOW. Alternatively, when the microphone plug is inserted,
pins 3 and 2 of the CN603 become open so that the Q603 goes OFF and the MIC_S signal goes HIGH.
From this signal, the CPU detects the microphone status.
The CPU turns the microphone SW on and off in the PCM Codec (IC601) for the external or the built-in
microphone, as appropriate.
ALC Amplifier (IC602: For the built-in microphone, IC603: For the external microphone)
Power Supply: 3.3V
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