uaa2073am NXP Semiconductors, uaa2073am Datasheet - Page 6

• Manufacturer Part Number: uaa2073am
• Description: Image Rejecting Front-end For Gsm Applications
• Manufacturer: NXP Semiconductors

Philips Semiconductors
Local oscillator section
The Local Oscillator (LO) input directly drives the two
internal all-pass networks to provide quadrature LO to the
receive mixers.
The LO differential input impedance is 50
part).
A synthesizer-on (SX) mode is used to power-up the
buffering on the LO inputs, minimizing the pulling effect on
the external VCO when entering transmit or receive
modes.
This mode is active when the SXON input is HIGH. Table 1
shows status of circuit in accordance with TXON, RXON
and SXON inputs.
1997 Jan 27
handbook, halfpage
Image rejecting front-end
for GSM applications
RXON
SXON
TXON
GND2
V CC2
Fig.4 Block diagram, LO section.
LOINA
QUAD
to RX
LOINB
MBH189
(parallel real
to TX
6
Transmit mixer
This mixer is used for down-conversion to the transmit IF.
Its inputs are coupled to the transmit RF and down-convert
it to a modulated transmit IF frequency which is phase
locked with the baseband modulation.
The transmit mixer provides a differential input at 200
and a differential output driver buffer for a 1 k load.
The IF outputs are low impedance (emitter followers).
Fast switching, on/off, of the transmit section is controlled
by the hardware input TXON.
handbook, halfpage
LOIN
Fig.5 Block diagram, transmit mixer.
TXON
TXINB
TX MIXER
TXINA
UAA2073AM
Product specification
MBH190
TXOIFA
TXOIFB