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U2891B Datasheet, PDF (1/6 Pages) TEMIC Semiconductors – 2.5 GHz Quadrature Up-Converter
TELEFUNKEN Semiconductors
U2891B
2.5 GHz Quadrature Up-Converter
Description
The U2891B is a silicon monolithic IC made with TELE-
FUNKEN’s advanced UHF process. The IC consists of a
500 MHz I/Q quadrature modulator and a 2.5 GHz mixer.
Both parts can be connected via an external filter in order
to suppress harmonics and spurious products. The device
features 3 V operation, a low current consumption and
furthermore two separate power-down functions for mod-
ulator and mixer. The RF ports are single ended and the
device can be operated adjustment free, but for optimiza-
tion also two pins for phase adjustment are provided.
These features and the double conversion concept of
U2891B make this device perfectly suited for all digital
radio applications from 900 MHz up to 2.5 GHz (e.g.,
GSM, DCS 1800, JDC, PHP and WLAN).
Features
D Low power consumption: 25 mA / 3 V
(typical at –8 dBm output level)
D 2.5 GHz output frequency
D Excellent sideband suppression by means of duty
cycle regeneration and 90° phase control
D Separate power-down mode for modulator and mixer
D Low LO input level: – 10 dBm (typical)
D LO and RF port 50-W single-ended
Benefits
D Extended talk time due to increased battery life
D Few external components results in cost and board
space saving
D Adjustment free, hence saves time and cost
D One TX Platform for different systems
D Reduced costs and space for battery (3-V operation)
Case: SSO-24 package
Ordering Information:
U2891B-AFS, U2891B-AFSG3 (see page 5)
Block Diagram
BBAi 2
3
BBAi
LO 1
4
Lo - Reg.
f/2f
50 LO 1 5
0°
90°
BBBi 22
23
BBBi
94 8141 e
10,17
GND
ö
Control
GND GND SIF
24 1 6
PDIF PDRF VS
14 13
Voltage
regulator
8, 21, 20
RFO
ȍ
16
19 18
LP 1 LP 2
7 11
IFO IFi
12 9
IFi LO2
15
SRF
50
Rev. A2: 04.10.1995
Advanced Information
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