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3. TECHNICAL BRIEF
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3.9.3. Charging control
A programmable charging block in PM6650 is used for battery charging. It is possible to set limits for
the charging current. The external supply typically connects directly to pin (VCHG). The voltage on this
pin (VCHG) is monitored by detection circuitry to ascertain whether a valid external supply is applied or
not. For additional accuracy or to capture variations over time, this voltage is routed internally to the
housekeeping ADC via the analog multiplexer. PM6650 circuits monitor voltages at VCHARGER and
ICHARGE pins to determine which supply should be used and when to switch between the two
supplies. These pins are connected to the Source (or emitter) and Drain (or collector) contacts of the
pass transistor respectively.
Figure 1.13 U250/KU250 Battery Bar Display(Stand By Condition)
4.2V~3.82V
100~70 (%)
3.81V~3.74V
69~45 (%)
3.73V~3.69V
44~20 (%)
3.68V~3.59V
19~3 (%)
3.58V~3.20V
2~0 (%)
Summary of Contents for U250
Page 1: ...Date June 2007 Issue 1 0 Service Manual Model U250 KU250 Service Manual U250 KU250 ...
Page 3: ... 4 ...
Page 20: ...3 TECHNICAL BRIEF 21 Fig 1 2 RTR6275 RX feature ...
Page 28: ...3 TECHNICAL BRIEF 29 Figure1 7 PM6650 Block Diagram ...
Page 41: ...3 TECHNICAL BRIEF 42 Table 1 2 Description of RF configurations ...
Page 45: ...3 TECHNICAL BRIEF 46 Figure 1 12 PM6650 Functional Block Diagram ...
Page 72: ...4 TROUBLE SHOOTING 73 4 1 RF Component 4 TROUBLE SHOOTING LGMC ...
Page 73: ...4 TROUBLE SHOOTING 74 Block Diagram Block Ref Name UMTS Part Name Function Comment ...
Page 77: ...4 TROUBLE SHOOTING 78 Check C312 of PMIC U300 Check R213 of MSM U201 T ...
Page 81: ...4 TROUBLE SHOOTING 82 ...
Page 84: ...4 TROUBLE SHOOTING 85 ...
Page 85: ...4 TROUBLE SHOOTING 86 4 7 Checking GSM Block 1 3 2 ...
Page 87: ...4 7 3 Checking RF Tx level 4 TROUBLE SHOOTING 88 ...
Page 90: ...4 TROUBLE SHOOTING 91 ...
Page 97: ...4 TROUBLE SHOOTING 98 R313 Q301 Q302 Q300 Charging part Main PCB Front ...
Page 107: ...4 TROUBLE SHOOTING 108 R422 R421 U401 ...
Page 109: ...4 TROUBLE SHOOTING 110 C401 C402 R406 C407 CN401 ...
Page 111: ...4 TROUBLE SHOOTING 112 Analog Switch Audio Amp SPK ...
Page 113: ...4 TROUBLE SHOOTING 114 MIC400 C417 R424 ...
Page 115: ...4 TROUBLE SHOOTING 116 Ear_Sense_N MIC Input ...
Page 117: ...4 TROUBLE SHOOTING 118 VPWR MOTOR_PWR ...
Page 134: ...6 BLOCK DIAGRAM 135 Table 2 1 RF Block Component ...
Page 136: ...6 BLOCK DIAGRAM 137 6 2 2 Memory Interface Fig 2 3 Memory Interface Diagram ADDRESS 14 0 ...
Page 137: ...6 BLOCK DIAGRAM 138 6 2 3 USB UART SIM JTAG Interface Fig 2 4 USB UART SIM JTAG Interface ...
Page 139: ...6 BLOCK DIAGRAM 140 6 2 4 Placement Top Side LGMC ...
Page 140: ...6 BLOCK DIAGRAM 141 Bottom Side LGMC ...
Page 141: ... 142 ...
Page 146: ... 147 LGMC 8 PCB LAYOUT U250 KU250 ...
Page 147: ... 148 LGMC 8 PCB LAYOUT U250 KU250 ...
Page 157: ... 158 ...
Page 174: ...Note ...
Page 175: ...Note ...