TDA5230XT Infineon Technologies, TDA5230XT Datasheet - Page 66

• Manufacturer Part Number: TDA5230XT
• Manufacturer: Infineon Technologies

Specifications of TDA5230XT

• Operating Temperature (min): -40C
• Operating Temperature (max): 105C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 4.4mm
• Product Length (mm): 9.7mm
• Lead Free Status / Rohs Status: Compliant

2.4.7
Figure 29
RFIN+ and RFIN- are inputs to the on chip LNA.
RF is usually connected to RFIN+, and RFIN- is grounded. If a filter with differential
outputs is used, such as a SAW filter, the differential inputs may be used accordingly.
The LNA directly drives the two in quadrature driven RF Mixers. The outputs of the two
mixers are fed to a polyphase filter that provides active suppression of input signals at
the image frequency of the desired input signal. The center frequency of the polyphase
filter and the following blocks at the IF frequency is 10.7 MHz.
The polyphase filter is followed by a digitally adjustable IF attenuator. This allows the
production spread of the on chip signal strip, of external LNA and matching circuitry and
RF SAW and ceramic IF filters to be trimmed out. The attenuator offers a programmable
attenuation range of 12 dB, programmable in 16 Steps and is controlled via the SFR
control bits IFATT. An IF driver amplifier with a characteristic output impedance of 330
allows simple interfacing to external ceramic IF filters.
For adjustment of the RSSI offset the complete RF path can be switched off via the SFR
control bit RFOFF.
Data Sheet
The RF mixer and poly phase filter are capable to support a Hi-Side and a Lo-Side LO
Injection mode. Selection of the LO Injection mode is controlled via the SFR-control bit
SSBSEL.
RFIN+
RFIN-
RF Path
LNA
RF Path
RF-Mixer
LO-Signals
I
Q
phase
Poly-
Filter
1
62
Amplifier
SUM-
IF-Attenuator
Adjustable
Digitally
0 .. -12 dB
4
Functional Description
Version 4.0, 2007-06-01
IF-
Driver-
Amp.
TDA523x
IF-OUT
Ω