U2760B Datasheet, PDF (1/14 Pages) TEMIC Semiconductors – CT2-RX/TX IC

CT2-RX/TX IC
U2760B
Description
The IC for digital cordless telephone application is
fabricated using TEMIC’s most advanced UHF process.
It covers the CT2 band (864 MHz to 868 MHz) as well as
the CT2 Plus band (up to 952 MHz). The RX/TX circuit
provides the down conversion to the data stream and the
up conversion from the first IF. In conjunction with
TEMIC’s RF front end, Twin PLL, I/Q modulator and
AMDs CT2 PhoX^TM controller AM 79C4xx a complete
CT2 IC kit is available.
Electrostatic sensitive device.
Observe precautions for handling.
Features
D Low supply voltage 2.9 V typical (min. 2.7 V)
D Provides down conversion to the data stream,
up conversion from the first IF
v ^{D Integrated UHF and VHF VCOs}
D Low noise figure of RX path (NF 10 dB)
D RX and TX power down
D First IF filter used for transmit as well receive mode
D Temperature compensated logarithmic Receiver
Signal Strength Indicator (RSSI) with a 75 dB
dynamic range
D Low power consumption in RX and TX mode
(<20 mA typ.)
D SSO28 plastic package
Benefits
D Low power consumption results in extended talk time
D Few external components and very small package
save space
Block Diagram (Simplified Schematic)
RX enable ₁₅
MX1 in ₂₁
VCO1 ref ₇
VCO1 tank
6
VCO1 out
5
MX4 outn ₂₂
MX4 outp
23
TX enable ₂₄
MX1/3 MX1/3 MX2/4 MX2/4
outp outn in nin
26 25 1 2
MX2 out
28
LIMIT in VCC
4
20
GND
19
MX1
MX2
LIMIT
RSSI
27 _{RSSI out}
VCO1
MX4
9
VCC
vco/lf
8
GND
vco/lf
VCO2
DEMOD ^{10 pF 11} QUAD
MX3
3
MX3 in
17 18 16
VCO2 VCO2 VCO2
ref tank out
12
100kW₁₃
COMP
100kW
10
14
RXdata
94 9532
DEMOD out
COMP in
COMP cap
Figure 1.
Rev. A3, 05-Oct-98
1 (14)