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TDMA StarTAC
TM
P8190:
Alert/Headset Detect
A
44
Description
When a headset is inserted in J650, the internal speaker and microphone is disabled. The user can now use the headset for handsfree conversation. BOOM_MIC_DET
informs U1000 whether a headset is inserted or not. The state of BOOM_MIC_DET is controlled by Q1551.
When the headset is inserted the biasing voltage for the AUX_MIC will no longer be present at the base of the NPN transistor Q1551. This will switch Q1551 off, thus,
allowing BOOM_MIC_DET to be pulled high. When the headset is not inserted, the AUX_MIC biasing voltage is present at the base of Q1551. This condition will
switch Q1551 on, thus, pulling the BOMM_MIC_DET to ground.
CR1071 and CR1070 are devices used for ESD protection for its corresponding line.
J650
EAR-
Headset Speaker
Headset Mic
AUX_MIC
Q1551
BOOM_MIC_DET
Summary of Contents for Timeport P8190
Page 1: ...DIGITAL WIRELESS TELEPHONE Model P8190 TDMA 800MHz Analog 800MHz Service Manual Level III ...
Page 3: ......
Page 28: ... 2000 Motorola Inc TDMA Timeport P8190 Cellular Overview 16 ...
Page 36: ...24 TDMA Timeport P8190 Accessories 2000 Motorola Inc ...
Page 44: ...Motorola Confidential Proprietary TDMA Timeport P8190 TDMA Test Mode NAM Programming 32 ...
Page 66: ...Motorola Confidential Proprietary TDMA Timeport P8190 Test Procedures 54 ...
Page 76: ...64 TDMA Timeport P8190 Disassembly Speaker Vibrator Removal Motorola Confidential Proprietary ...
Page 88: ...76 TDMA Timeport P8190 Parts List Motorola Confidential Proprietary ...