uaa2073m NXP Semiconductors, uaa2073m Datasheet - Page 5

• Manufacturer Part Number: uaa2073m
• Description: Image Rejecting Front-end For Gsm Applications
• Manufacturer: NXP Semiconductors

Philips Semiconductors
FUNCTIONAL DESCRIPTION
Receive section
The circuit contains a low-noise amplifier followed by two
high dynamic range mixers. These mixers are of the
Gilbert-cell type. The whole internal architecture is fully
differential.
The local oscillator, shifted in phase to 45 and 135 ,
mixes the amplified RF to create I and Q channels. The
two I and Q channels are buffered, phase shifted by 45
and 135 respectively, amplified and recombined internally
to realize the image rejection.
Pin SBS allows sideband selection:
1995 Dec 07
f
f
Image rejecting front-end
for GSM applications
LO
LO
handbook, full pagewidth
< f
> f
RF
RF
(SBS = 1)
(SBS = 0).
RFINA
RFINB
GND1
V CC1
SYNTHON
LNA
Fig.3 Block diagram, receive section.
MIXER
MIXER
LOIN
amplifier
amplifier
IF
IF
5
Balanced signal interfaces are used for minimizing
crosstalk due to package parasitics. The RF differential
input impedance is 150
minimize current consumption at best noise performance.
The IF output is differential and of the open-collector type,
tuned for 71 MHz. Typical application will load the output
with a differential 500
each IF output, plus a 1 k to x
network (x
The path to V
inductors. The output voltage is limited to V
3 diode forward voltage drops.
Fast switching, on/off, of the receive section is controlled
by the hardware input RXON.
135
45
o
o
RXON
being the input impedance of the IF filter).
CC
for the DC current is achieved via tuning
COMBINER
SBS
IF
load; i.e. a 500
(parallel real part), choosen to
MBG795
narrow band matching
Product specification
UAA2073M
IFA
IFB
resistor load at
CC
+ 3V
be
or