4 oscillator and crystal, 1 schematic, 2 parameters – Atmel AT89C5132 User Manual
Page 17: 5 phase lock loop
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4173ES–USB–09/07
AT89C5132
6.2.4
Oscillator and Crystal
6.2.4.1
Schematic
Figure 6-4.
Crystal Connection
Note:
For operation with most standard crystals, no external components are needed on X1 and X2. It
may be necessary to add external capacitors on X1 and X2 to ground in special cases (max 10
pF). X1 and X2 may not be used to drive other circuits.
6.2.4.2
Parameters
Table 3. Oscillator and Crystal Characteristics
V
DD
= 2.7 to 3.3V , T
A
= -40 to +85
°
C
6.2.5
Phase Lock Loop
6.2.5.1
Schematic
Figure 6-5.
PLL Filter Connection
VSS
X1
X2
Q
C1
C2
Symbol
Parameter
Min
Typ
Max
Unit
C
X1
Internal Capacitance (X1 -
V
SS
)
10
pF
C
X2
Internal Capacitance (X2 -
V
SS
)
10
pF
C
L
Equivalent Load Capacitance (X1 - X2)
5
pF
DL
Drive Level
50
μ
W
F
Crystal Frequency
20
MHz
RS
Crystal Series Resistance
40
Ω
CS
Crystal Shunt Capacitance
6
pF
VSS
FILT
R
C1
C2
VSS