TDA5220XT Infineon Technologies, TDA5220XT Datasheet - Page 16

• Manufacturer Part Number: TDA5220XT
• Manufacturer: Infineon Technologies

Specifications of TDA5220XT

• Operating Temperature (min): -40C
• Operating Temperature (max): 125C
• Operating Temperature Classification: Automotive
• Product Depth (mm): 4.4mm
• Product Length (mm): 9.7mm
• Operating Supply Voltage (min): 4.5V
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.5V
• Lead Free Status / Rohs Status: Compliant

2.4.2
The Double Balanced Mixer downconverts the input frequency (RF) in the range of 400-
440MHz/810-870MHz to the intermediate frequency (IF) at 10.7MHz with a vol-tage gain
of approximately 21dB by utilising either high- or low-side injection of the local oscillator
signal. In case the mixer is interfaced only single-ended, the unused mixer input has to
be tied to ground via a capacitor. The mixer is followed by a low pass filter with a corner
frequency of 20MHz in order to suppress RF signals to appear at the IF output (IFO pin).
The IF output is internally consisting of an emitter follower that has a source impedance
of approximately 330
ceramic filter without additional matching circuitry.
2.4.3
The Phase Locked Loop synthesizer consists of a VCO, an asynchronous divider chain,
a phase detector with charge pump and a loop filter and is fully implemented on-chip.
The VCO is including spiral inductors and varactor diodes. The tuning range of the VCO
guarantee over production spread and the specified temperature range is 820 and
860MHz. The oscillator signal is fed both to the synthesiser divider chain and to the
downconverting mixer. In case of operation in the 400 to 440MHz range the signal is
divided by two before it is fed to the Mixer. Depending on whether high- or low-side
injection of the local oscillator is used, the receiving frequency ranges are 810 to
840MHz and 840 to 870MHz or 400 to 420MHz and 420 to 440MHz - see also Section
3.4. To be able to switch between two different frequency channels a divider ratio of
either 32 or 32.25 can be selected via the FSEL-Pin.
Table 2
FSEL
Open
GND
2.4.4
The calculation of the value of the necessary crystal load capacitance is shown in
Section 3.3, the crystal frequency calculation is explained in Section 3.4.
2.4.5
The Limiter is an AC coupled multistage amplifier with a cumulative gain of
approximately 80 dB that has a bandpass-characteristic centred around 10.7 MHz. It
has a typical input impedance of 330
ceramic IF filter. The limiter circuit also acts as a Receive Signal Strength Indicator
(RSSI) generator which produces a DC voltage that is directly proportional to the input
Preliminary Specification
Mixer
PLL Synthesizer
Crystal Oscillator
Limiter
FSEL-Pin Operating States
to facilitate interfacing the pin directly to a standard 10.7MHz
to allow for easy interfacing to a 10.7 MHz
16
RF
400-440MHz
810-870MHz
Functional Description
V 1.1, 2004-10-20
TDA 5220