3. TECHNICAL BRIEF
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3.5.5 UMTS transmit power detector (U105)
This detector couples PA output power level to calibrate the transmitter characteristic over the channel
variation and temperature. Its detector coupling range and converted voltage is based on diode
sensitivity and transmitter power level.
The U890 uses National Semiconductor LMV225TLX power detector IC. In Figure 3.5.5-1, R1 is set to
1.8kΩ resulting in an attenuation of 31.4dB. The output voltage is proportional to the logarithm of the
input power. Figure3.5.5-2 shows the output voltage versus PA output power of the LMV225TLX setup
as depicted in Figure3.5.5-1
Figure 3.5.5-1 Block diagram of LMV225TLX with high resistive tap
Figure 3.5.5-2 Power detector respones, Vout vs PA output power
Содержание U890
Страница 1: ...Date April 2006 Issue 1 0 Service Manual Model U890 U890c Service Manual U890 U890c ...
Страница 3: ... 4 ...
Страница 20: ...3 TECHNICAL BRIEF 21 ...
Страница 46: ...3 TECHNICAL BRIEF 47 Figure PM6650 2 Functional Block Diagram ...
Страница 70: ...4 TROUBLE SHOOTING 71 4 2 SIGNAL PATH ...
Страница 109: ...4 TROUBLE SHOOTING 110 CN600 50pin LCD connector CN901 C907 C911 FB901 FB902 ...
Страница 115: ...4 TROUBLE SHOOTING 116 C226 C227 for MIC serial capacitor ...
Страница 118: ...4 TROUBLE SHOOTING 119 Q400 Q401 Q402 VBATT GND ...
Страница 139: ...Table 2 1 1 RF Block Component 6 BLOCK DIAGRAM 140 ...
Страница 140: ...6 BLOCK DIAGRAM 141 6 2 Interface Diagram U890 Interface Diagram ...
Страница 142: ...6 BLOCK DIAGRAM 143 Top Side ...
Страница 143: ...6 BLOCK DIAGRAM 144 Bottom Side ...
Страница 152: ... 153 8 pcb layout ...
Страница 153: ... 154 8 pcb layout ...
Страница 154: ... 155 8 pcb layout ...
Страница 155: ... 156 8 pcb layout ...
Страница 156: ... 157 8 pcb layout ...
Страница 157: ... 158 8 pcb layout ...
Страница 163: ...9 CALIBRATION 164 9 3 HOT KIMCHI Example Choose_U890 ...
Страница 164: ...9 CALIBRATION 165 Click APPLY button Click START button ...
Страница 165: ...9 CALIBRATION 166 Click Run button to lunch RF AUTOTEST ...
Страница 167: ... 168 ...
Страница 191: ...Note ...
Страница 192: ...Note ...