Datasheet

LPC185X_3X_2X_1X All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 4.1 — 6 May 2014 128 of 148
NXP Semiconductors
LPC185x/3x/2x/1x
32-bit ARM Cortex-M3 microcontroller
12 MHz < 160  18 pF, 18 pF
< 160  39 pF, 39 pF
16 MHz < 120  18 pF, 18 pF
< 80  33 pF, 33 pF
20 MHz < 100  18 pF, 18 pF
< 80  33 pF, 33 pF
Table 40. Recommended values for C
X1/X2
in oscillation mode (crystal and external
components parameters) high frequency mode
Fundamental oscillation
frequency
Maximum crystal series
resistance R
S
External load capacitors C
X1
,
C
X2
15 MHz < 80  18 pF, 18 pF
20 MHz < 80  39 pF, 39 pF
< 100  47 pF, 47 pF
Fig 40. Slave mode operation of the on-chip oscillator
Fig 41. Oscillator modes with external crystal model used for C
X1
/C
X2
evaluation
Table 39. Recommended values for C
X1/X2
in oscillation mode (crystal and external
components parameters) low frequency mode
Fundamental oscillation
frequency
Maximum crystal series
resistance R
S
External load capacitors
C
X1
, C
X2
LPC1xxx
XTAL1
C
i
100 pF
C
g
002aae835
002aag031
LPC18xx
XTAL1 XTAL2
C
X2
C
X1
XTAL
=
C
L
C
P
R
S
L