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RX Frequency and Channel Range
GSM 850:
Frequency Range: 869,2 MHZ – 893,8 MHZ
Channel Range: 128 – 251
GSM 900:
Frequency Range: 935,2 MHZ – 959,8 MHZ
Channel Range: 1 - 124
EGSM 900:
Frequency Range: 925,2 MHZ – 934,8 MHZ
Channel Range: 975 – 1023
DCS 1800:
Frequency Range: 1805,2 MHZ – 1879,8 MHZ
Channel Range: 512 – 885
PCS 1900:
Frequency Range: 1930,2 MHZ – 1989,8 MHZ
Channel Range: 512 - 810
WCDMA
N1300 (RF 3100) is an integrated transceiver intended for the Universal Mobile
Telecommunication System (UMTS). The circuit is specially designed for the Frequency
Division Duplex (FDD) mode of the Wideband Code Division Multiple Access (WCDMA) that
operates in
Band I (TX Frequency Range: 1920-1980 MHz, RX Frequency Range: 2110-2170 MHz).
The baluns, loop filters and most of the passive components are included in the package.
The WCDMA transceiver has the following features:
• System in Package solution
• Single band application (UMTS band I)
• High Speed Downlink Packet Access (HSDPA) capability
• Variable duplex in band I
• Fully integrated TX baluns, loop filters and decoupling capacitors
• Low noise, wide dynamic range for zero IF RX and TX
• RX 87 dB gain control range in increments of 1 dB
• TX 80 dB gain analog control range; 1 dB minimum resolution
• RX 99 dB voltage gain
• Maximum TX output power at least +5dBm average
• Integrated RX channel filters (band I)
• RX & TX fully integrated fractional-N synthesizer with AFC control capability
• RX & TX fully integrated RF VCO with integrated supply voltage regulator
• Supply voltage from 2.6 V to 3.0 V
• 3-wire serial interface bus
• HVQFN40 package
• Lead-free
Frequency Generation
The transmitter and receiver frequency synthesizers and the VCOs are fully integrated in
the WCDMA radio circuit. The signal from the crystal oscillator is used as a reference for
the synthesizers. The two synthesizers are controlled through the serial bus from the
access subsystem of the digital baseband controller.
FUNCTIONAL OVERVIEW
Technical Description
WCDMA Transceiver Block Diagram
Transmitter
The TX IQ modulator has differential voltage I and Q inputs. It converts input signals to
RF output frequency and is designed to achieve LO and image suppression.
The transmit output stage provides at least +5 dBm at maximum power control at the
single-ended 50 Ω output. Gain is set through the 3-wire bus.
Two 10-bit DAC-s are used to control the DC/DC converter and the PA gain.
These DAC-s are controlled through the 3-wire bus.
Receiver
The front-end receiver converts the aerial RF signal from WCDMA band I down to a Zero
Intermediate Frequency (ZIF). The first stage consists of one single-ended low noise
amplifier (LNA) with a 16 dB gain step. This LNA is followed through an external filter by
an IQ down-mixer which consists of a mixer in parallel driven by quadrature out-of-phase
LO signals. The In phase (I) and Quadrature phase (Q) ZIF signal are then low pass
filtered to provide protection from high frequency offset interferer fed into the channel
filter. The front-end zero IF I and Q outputs are applied to the integrated low-pass channel
filter with a provision for 4 x 8 dB gain steps in front of the filter. The filter is a self-calibrated
6 pole, 2 zero filter with a cut-off frequency around 2.15 MHz and a second order group delay
compensation (2 poles, 2 zeroes). Once filtered, the zero IF I and Q signals are
further amplified with provision of 31 x 1 dB steps and DC offset compensation.
The zero IF output buffer provides close rail-to-rail output signals.
SEMC Troubleshooting Manual
W890
1217-3942 rev. 1
87
(119)
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Troubleshooting
