3.5.6 Dual band GSM power amplifier (U1005)
The SKY77328 Power Amplifier Module (PAM) is designed in a low profile (1.2mm), compact form
factor for quad-band cellular handsets comprising GSM850/900, DCS1800, and PCS1900 operation.
The PAM also supports Class 12 General Packet Radio Service (GPRS) multi-slot operation.
The module consists of separate GSM850/900 PA and DCS1800/PCS1900 PA blocks, impedance-
matching circuitry for 50 Ω input and output impedances, and a Power Amplifier Control (PAC) block
with an internal current-sense resistor. The custom BiCMOS integrated circuit provides the internal
PAC function and interface circuitry.
Fabricated onto a single Gallium Arsenide (GaAs) die, one Heterojunction Bipolar Transistor (HBT) PA
block supports the GSM850/900 bands and the other supports the DCS1800 and PCS1900 bands.
Both PA blocks share common power supply pins to distribute current. The GaAs die, the Silicon (Si)
die, and the passive components are mounted on a multi-layer laminate substrate. The assembly is
encapsulated with plastic overmold.
RF input and output ports of the SKY77328 are internally matched to a 50 Ω load to reduce the
number of external components for a quad-band design.
Extremely low leakage current (2.5 µA, typical) of the dual PA module maximizes handset standby
time. The SKY77328 also contains band-select switching circuitry to select GSM (logic 0) or DCS/PCS
(logic 1) as determined from the Band Select (BS) signal. In Figure 1.5.6-1 below, the BS pin selects
the PA output (DCS/PCS OUT or GSM850/900 OUT) and the Analog Power Control (VAPC) controls
the level of output power.
The VBATT pin connects to an internal current-sense resistor and interfaces to an integrated power
amplifier control (iPAC™) function, which is insensitive to variations in temperature, power supply,
process, and input power. The ENABLE input allows initial turn-on of PAM circuitry to minimize battery
drain.
3. TECHNICAL BRIEF
- 32 -
Figure 3.5.5-2 Power detector response, Vout vs PA output power
Содержание U8500
Страница 1: ...Date February 2006 Issue 1 0 Service Manual Model U8500 Service Manual U8500 ...
Страница 20: ...3 TECHNICAL BRIEF 21 ...
Страница 32: ...3 TECHNICAL BRIEF 33 Figure 3 5 6 1 GSM PA functional block diagram ...
Страница 35: ...3 TECHNICAL BRIEF 36 Figure 3 5 10 1 Bluetooth system architecture ...
Страница 50: ...3 TECHNICAL BRIEF 51 Figure 3 10 3 2 1 PM6650 Functional Block Diagram ...
Страница 110: ...4 TROUBLE SHOOTING 111 R605 R606 receiver signal serial resistor Receiver CN600 50pin LCD connector FPCB for LCD Module ...
Страница 112: ...4 TROUBLE SHOOTING 113 R605 R606 receiver signal serial resistor CN600 50pin LCD connector CN901 C907 C911 ...
Страница 114: ...4 TROUBLE SHOOTING 115 Loud Speaker U502 U503 Amp ...
Страница 118: ...4 TROUBLE SHOOTING 119 C200 C201 for MIC serial capacitor ...
Страница 121: ...4 TROUBLE SHOOTING 122 Q404 Q403 Q402 VBATT GND ...
Страница 128: ...5 DOWNLOAD 129 5 Choose a Module Image file after clicking on the Browse button U8500 U8500 U8500 U8500 U8500 U8500 ...
Страница 132: ...5 DOWNLOAD 133 Downloading the AMSS Modem image Rebooting and waiting for a while Performing NV restore ...
Страница 134: ...5 DOWNLOAD 135 Download of Module image in progress Download process has completed successfully ...
Страница 143: ...6 BLOCK DIAGRAM 144 6 3 Interface Diagram U8500 Interface Diagram ...
Страница 145: ... 146 ...
Страница 154: ... 155 U8500 8 PCB LAYOUT ...
Страница 155: ... 156 8 PCB LAYOUT U8500 ...
Страница 156: ... 157 8 PCB LAYOUT ...
Страница 157: ... 158 8 PCB LAYOUT ...
Страница 158: ... 159 U8500 8 PCB LAYOUT ...
Страница 159: ... 160 U8500 8 PCB LAYOUT ...
Страница 166: ...9 CALIBRATION 167 Click START button U8500 U8500_ver1 1 U8500 U8500 Click U8500 ...
Страница 167: ... 168 ...
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Страница 194: ...Note ...
Страница 195: ...Note ...