Motorola Tarpon V. 120C, Руководство по обслуживанию

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V.120c
© 2001 Motorola, Inc. 52
Troubleshooting
Power Select, Charger & Vibrator: A10
POWER SELECT: A10
1.
Power select circuit enables the phone to draw the current either from battery or Ext_B+
2. When voltage at Ext_B+ is present (more than 3.59V) the circuit disconnects the Battery from B+.
3. The circuit consists of Q2005 (switch), U2200 and Q2006.
4. Q2005 acts like a switch which connects or disconnects battery (Batt+) to B+.
5. Q2006 forces Q2005 to turn on and connect Battery to B+ when a mid rate charger is attached and the phone
in a call. This is done with the help of a signal from Wally IC called Mid Rate 2.
6. Q2006 will only turn on, therefore U2200 is used to turn the Q2005 off once the is over.
7. U2200 will only turn off the switch (isolate Batt+ and B+).
INTERNAL CHARGER: A10
1.
CHARGING OF THE BATTERY TAKES PLACE THROUGH q2007.
2. Current flows from through Q2007 to the BATT+.
3. CHRGC is the signal from the CCAP IC controls the flow of current through Q2007 through Gate bisasing.
4. Wally IC controls the CCAP IC by writing into the DAC inside the CCAP and ISENSE input into the CCAP
IC compare it with the DAC and the result is CHRGC signal.
5. Other signals that help in this charging process are Battery Thermistor sense, Battery Serial data and Batt+.
6. CR2003 diode prevents the reverse leakage of current.
VIBRATOR: A10
1. CCAP IC produces the vibrator drive signal which is the output of V9 regulator inside the IC and is produce when
you select the feature and WALLY IC sends the command to CCAP IC