ELANSC310 AMD [Advanced Micro Devices], ELANSC310 Datasheet - Page 85

• Manufacturer Part Number: ELANSC310
• Description: Single-Chip, 32-Bit, PC/AT Microcontroller
• Manufacturer: AMD [Advanced Micro Devices]

frequency. It is therefore required that the load capaci-
tance in the oscillator circuit is duplicated as closely as
possible to the manufacturer’s load capacitance speci-
fication.
The crystal load capacitance in the circuit consists of
the capacitor network C
work reduces to (C
combination of C
ries combination of C
C
pacitance specification.
Notes:
For board layout suggestions, refer to the ÉlanSC310 Microcontroller Evaluation Board User’s Manual available in PDF format
on the AMD web site.
The series combination of C
STRAY
A
), where C
XTAL
L
D
is the crystal manufacturer’s load ca-
O
and C
+ C
-------------------------- -
C
C
D
STRAY
D
O
and C
D
, C
G
B
+
. Therefore, the desired se-
STRAY
C
D
C
) in parallel with the series
X32IN (201)
G
G
G
and C
is equal to C
, C
A
D
Élan™SC310 Microcontroller Data Sheet
, and C
G
R
L
B
1
C
Figure 29. X32 Oscillator Circuit
=
D
P R E L I M I N A R Y
G
. This net-
L
– (C
ÉlanSC310 Microcontroller
O
C
C
+
STRAY
C
1
O
C
can be assumed and experimentation will determine
the optimal value for C
ternal component values to provide the optimal operat-
ing frequency, there are some recommended limits to
ensure a reasonable start-up time for the oscillator cir-
cuit. These limits are shown in Table 43.
R
Table 43. Recommended Oscillator Component
F
STRAY
C
R
R
C
D
G
F
B
is typically difficult to determine. Some value
C
R
G
1
Minimum
B
14 M
10 pF
10 pF
Value Limits
0
D
and C
X32OUT (202)
G
. In determining the ex-
Maximum
18 M
10 k
30 pF
30 pF
85