tda8295 NXP Semiconductors, tda8295 Datasheet - Page 67

• Manufacturer Part Number: tda8295
• Description: Tda8295 Digital Global Standard Low If Demodulator For Analog Tv And Fm Radio
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8295_1
Product data sheet
13.7 Crystal connection
The typical crystal frequency value is 16 MHz. The values of the passive components
depend on crystal manufacturer. The oscillator can be set in two configurations depending
on the origin of the crystal.
tuner and the TDA8295 (Slave mode),
TDA8295 (Oscillator mode).
In Oscillator mode, only a crystal and the load capacitances C1 and C2 need to be
connected externally since the feedback resistance is integrated on chip. In this mode the
oscillator gain stage can have a normal or large transconductance, determined by the HF
bit (see also
frequencies, higher series resistance of the crystal and higher external load capacitors.
For an accurate time reference it is advised to use the load capacitors as specified in
Table
crystal manufacturer.
Table 69.
Fundamental
oscillation
frequency
Bit HF = 0
1 MHz to 5 MHz
5 MHz to 10 MHz
10 MHz to
15 MHz
15 MHz to
20 MHz
Fig 14. Reference clock application
69. C
Slave mode
Crystal parameters together with external components
L
Table
clock signal
is the typical load capacitance of the crystal and is usually specified by the
from tuner
XIN
Digital global standard low IF demodulator for analog TV and FM radio
100 nF
Crystal load
capacitance
C
10
20
30
10
20
30
10
20
10
TDA8295
61). A large transconductance is required for higher oscillation
L(xtal)
R bias
Rev. 01 — 4 February 2008
(pF)
001aah363
n.c.
Figure 14
XOUT
Crystal series
resistance
R
< 300
< 300
< 300
< 300
< 200
< 100
< 160
< 60
< 80
describes the case of an crystal shared with the
s(xtal)
Figure 15
( )
Fig 15. Oscillator application
the case of an crystal dedicated to the
Oscillator mode
External load capacitors
C1 (pF)
18
39
56
18
39
56
18
39
18
XIN
GND
C1
TDA8295
R bias
XTAL
TDA8295
GND
© NXP B.V. 2008. All rights reserved.
001aah364
C2 (pF)
18
39
56
18
39
56
18
39
18
XOUT
C2
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