5-39
RF2483
Rev A8 060203
Pin
Function
Description
Interface Schematic
7LOLB
Local oscillator input low band.
This input is biased internally at around 1.6V when the chip is in low
band mode and 0V when the chip is in high band mode or powered
down. The LO signal typically needs to be AC coupled.
The noise performance, carrier suppression at low output powers and
sideband suppression are all a function of LO power.
The optimum LO power is between 0dBm and 3dBm.
The device will work with LO powers as low as -20dBm however this is
at the expense of higher noise performance at high output powers and
poorer sideband suppression.
8GND LO
Ground return for the local oscillator input signals.
The GND LO pin is effectively the complementary LO input for both the
high band and low band LO signals. It has significant amounts of LO
signal flowing through it. This pin is brought out as an independent
ground to enable the PCB board designer to isolate the LO return from
the RF outputs ground and the general chip ground.
It is recommended that this ground is kept isolated from the die flag
ground. Any connections between the GND LO and any other ground
should be made through a ground plane.
See pins 7 and 9.
9LOHB
Local oscillator input high band.
This input is biased internally at around 1.6V when the chip is in high
band mode and 0V when the chip is in low band mode or powered
down. The LO HB signal typically needs to be AC coupled.
The noise performance, carrier suppression at low output powers and
sideband suppression are all a function of LO power.
The optimum LO power is between 0dBm and 3dBm.
The device will work with LO powers as low as -20dBm however this is
at the expense of higher noise performance at high output powers and
poorer sideband suppression.
10
GND1
Ground for LO buffers.
See pin 6.
11
BAND SEL
Band select input to define active mode.
CMOS input.
Logic 1 (1.4V to VCC)=High band mode.
Logic 2 (0V to 0.5V)=Low band mode.
12
QSIG N
Quadrature channel negative baseband input port. See QSIGP.
LOLB
GNDLO
LOHB
GND LO
V
CC2
V
CC2
12 pF
50
Ω
Chinese ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
