TDA6651TTC1 NXP Semiconductors, TDA6651TTC1 Datasheet - Page 45

• Manufacturer Part Number: TDA6651TTC1
• Manufacturer: NXP Semiconductors

Specifications of TDA6651TTC1

• Package Type: TSSOP
• Lead Free Status / Rohs Status: Compliant

NXP Semiconductors
13. Application information
TDA6650TT_6651TT_5
Product data sheet
13.1 Tuning amplifier
13.2 Crystal oscillator
13.3 Examples of I
The tuning amplifier is capable of driving the varicap voltage without an external transistor.
The tuning voltage output must be connected to an external load of 15 k which is
connected to the tuning voltage supply rail. The loop filter design depends on the oscillator
characteristics and the selected reference frequency as well as the required PLL loop
bandwidth.
Applications with the TDA6650TT; TDA6651TT have a large loop bandwidth, in the order
of a few tens of kHz. The calculation of the loop filter elements has to be done for each
application, it depends on the reference frequency and charge pump current.
The TDA6650TT; TDA6651TT needs to be used with a 4 MHz crystal in series with a
capacitor with a typical value of 18 pF, connected between pin XTAL1 and pin XTAL2.
NXP crystal 4322 143 04093 is recommended. When choosing a crystal, take care to
select a crystal able to withstand the drive level of the TDA6650TT; TDA6651TT without
suffering from accelerated ageing. For optimum performances, it is highly recommended
to connect the 4 MHz crystal without any serial resistance.
The crystal oscillator of the TDA6650TT; TDA6651TT should not be driven (forced) from
an external signal.
Do not use the signal on pin XTAL1 or pin XTAL2, or the signal present on the crystal, to
drive an external IC or for any other use as this may dramatically degrade the phase noise
performance of the TDA6650TT; TDA6651TT.
Table 23
The following conditions apply:
S = START
A = acknowledge
P = STOP.
LO frequency is 800 MHz
f
Divider ratio (programmable) N = 4800
BS3 output port is on and all other ports are off: thus the high band is selected
Charge pump current I
Normal mode, with XTOUT buffer on
I
AGC take-over point is set to 112 dB V (p-p)
Address selection is adjusted to make address C2 valid.
comp
AGC
= 220 nA
= 166.666 kHz
to
30
show various sequences where:
2
C-bus program sequences
Rev. 05 — 10 January 2007
CP
= 280 A
5 V mixer/oscillator and low noise PLL synthesizer
TDA6650TT; TDA6651TT
© NXP B.V. 2007. All rights reserved.
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