Philips LPC2101 User Manual page 17

Philips Semiconductors
Volume 1
In slave mode the input clock signal should be coupled by means of a capacitor of 100 pF
(C
configuration can be left not connected. If slave mode is selected, the F
duty cycle can range from 1 MHz to 50 MHz.
External components and models used in oscillation mode are shown in
drawings b and c, and in
a crystal and the capacitances C
fundamental mode oscillation (the fundamental frequency is represented by L, C
R
and should not be larger than 7 pF. Parameters F
crystal manufacturer.
Choosing an oscillation mode as an on-board oscillator mode of operation limits F
clock selection to 1 MHz to 30 MHz.
LPC2101/02/03
X1 X2
C
C
Clock
a)
Fig 6. Oscillator modes and models: a) slave mode of operation, b) oscillation mode of operation, c) external
crystal model used for C
Table 7:
Fundamental
oscillation frequency
F
5 MHz - 10 MHz
10 MHz - 15 MHz
User manual
in Figure 6, drawing a), with an amplitude of at least 200 mVrms. The X2 pin in this
C
). Capacitance C in Figure
S P
LPC2101/02/03
X1
C
X1
/ evaluation
X1 X2
Recommended values for C
components parameters)
Crystal load
capacitance C
OSC
1 MHz - 5 MHz 10 pF
20 pF
30 pF
10 pF
20 pF
30 pF
10 pF
20 pF
30 pF
Rev. 01 — 12 January 2006
Table 7. Since the feedback resistance is integrated on chip, only
and C need to be connected externally in case of
X1 X2
6, drawing c, represents the parallel package capacitance
X2
Xtal
C
X2
b)
in oscillation mode (crystal and external
X1/X2
Maximum crystal
series resistance R
L
NA
NA
< 300 Ω
< 300 Ω
< 300 Ω
< 300 Ω
< 300 Ω
< 220 Ω
< 140 Ω
UM10161
Chapter 3: System control block
OSC
Figure
, C , R and C are supplied by the
C L S P
< = >
c)
External load
capacitors C
S
NA
NA
58 pF, 58 pF
18 pF, 18 pF
38 pF, 38 pF
58 pF, 58 pF
18 pF, 18 pF
38 pF, 38 pF
58 pF, 58 pF
© Koninklijke Philips Electronics N.V. 2006. All rights reserved.
signal of 50-50
6,
and
L
OSC
L
C
C
L
P
R
S
,
X1 CX2
17