TDA6650ATT NXP [NXP Semiconductors], TDA6650ATT Datasheet - Page 40

• Manufacturer Part Number: TDA6650ATT
• Description: 5 V mixer/oscillator and low noise PLL synthesizer for hybrid terrestrial tuner (digital and analog)
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
TDA6650ATT_6651ATT_2
Product data sheet
The TDA6650ATT; TDA6651ATT PLL loop stability is guaranteed in the configuration of
the
minimum, the pull-up resistor, R19 is 15 k and all of the local oscillators are aligned to
operate at a maximum tuning voltage of 26 V. If the configuration is changed, there might
be an impact on the loop stability.
For any other configurations, a stability analysis must be performed. The conventional PLL
AC model used for the stability analysis, is valid provided the external source (DC supply
source or DC-to-DC converter) is able to deliver a minimum current that is equal to the
charge pump current in use.
The delivered current can be simply calculated with the following formula:
where:
I
V
V
R
output) and the tuning line (R19 in
I
I
delivered
CP
delivered
DC
T
pu
is the tuning voltage.
is the charge pump current in use.
Figure 27
is the pull-up resistor between the DC supply source (or the DC-to-DC converter
is the supply source voltage or DC-to-DC converter output voltage.
is the delivered current.
=
V
------------------------
to
DC
Figure
R
pu
–
V
T
Rev. 02 — 2 February 2007
30. In this configuration, the external supply source is 30 V
I
CP
TDA6650ATT; TDA6651ATT
Figure 27
5 V mixer/oscillator and low noise PLL synthesizer
to
Figure
30).
© NXP B.V. 2007. All rights reserved.
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