© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
User manual
Rev. 01 — 15 August 2005
19
Philips Semiconductors
UM10139
Volume 1
Chapter 3: System Control Block
Fig 6.
Oscillator modes and models: a) slave mode of operation, b) oscillation mode of
operation, c) external crystal model used for C
X1
/
X2
evaluation
Table 7:
Recommended values for C
X1/X2
in oscillation mode (crystal and external
components parameters)
Fundamental
oscillation frequency
F
OSC
Crystal load
capacitance C
L
Maximum crystal
series resistance R
S
External load
capacitors C
X1
,
CX2
1 MHz - 5 MHz
10 pF
NA
NA
20 pF
NA
NA
30 pF
< 300
Ω
58 pF, 58 pF
5 MHz - 10 MHz
10 pF
< 300
Ω
18 pF, 18 pF
20 pF
< 300
Ω
38 pF, 38 pF
30 pF
< 300
Ω
58 pF, 58 pF
10 MHz - 15 MHz
10 pF
< 300
Ω
18 pF, 18 pF
20 pF
< 220
Ω
38 pF, 38 pF
30 pF
< 140
Ω
58 pF, 58 pF
15 MHz - 20 MHz
10 pF
< 220
Ω
18 pF, 18 pF
20 pF
< 140
Ω
38 pF, 38 pF
30 pF
< 80
Ω
58 pF, 58 pF
20 MHz - 25 MHz
10 pF
< 160
Ω
18 pF, 18 pF
20 pF
< 90
Ω
38 pF, 38 pF
30 pF
< 50
Ω
58 pF, 58 pF
25 MHz - 30 MHz
10 pF
< 130
Ω
18 pF, 18 pF
20 pF
< 50
Ω
38 pF, 38 pF
30 pF
NA
NA
LPC2141/2/4/6/8
LPC2141/2/4/6/8
X1
X1
X2
X2
Clock
C
C
C
X1
C
X2
C
L
C
P
L
R
S
< = >
a)
b)
c)
Xtal