LPC1765FET100 NXP Semiconductors, LPC1765FET100 Datasheet - Page 69

• Manufacturer Part Number: LPC1765FET100
• Description: The LPC1765 is a Cortex-M3 microcontroller for embedded applications featuring a high level of integration and low power consumption at frequencies of 100 MHz
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC1769_68_67_66_65_64_63
Product data sheet
14.3 XTAL and RTCX Printed Circuit Board (PCB) layout guidelines
Table 22.
Table 23.
The crystal should be connected on the PCB as close as possible to the oscillator input
and output pins of the chip. Take care that the load capacitors C
third overtone crystal usage have a common ground plane. The external components
must also be connected to the ground plain. Loops must be made as small as possible in
Fundamental oscillation
frequency F
5 MHz - 10 MHz
10 MHz - 15 MHz
15 MHz - 20 MHz
Fundamental oscillation
frequency F
15 MHz - 20 MHz
20 MHz - 25 MHz
1 MHz - 5 MHz
Fig 34. Oscillator modes and models: oscillation mode of operation and external crystal
model used for C
Recommended values for C
components parameters): low frequency mode
Recommended values for C
components parameters): high frequency mode
OSC
OSC
All information provided in this document is subject to legal disclaimers.
XTALIN
C X1
LPC1xxx
Rev. 8 — 14 November 2011
XTAL
X1
Crystal load
capacitance C
10 pF
20 pF
30 pF
10 pF
20 pF
30 pF
10 pF
20 pF
10 pF
Crystal load
capacitance C
10 pF
20 pF
10 pF
20 pF
/C
X2
XTALOUT
evaluation
LPC1769/68/67/66/65/64/63
C X2
X1
X1
/C
/C
L
L
X2
X2
in oscillation mode (crystal and external
in oscillation mode (crystal and external
Maximum crystal
series resistance R
< 300 
< 300 
< 300 
< 300 
< 200 
< 100 
< 160 
< 60 
< 80 
Maximum crystal
series resistance R
< 180 
< 100 
< 160 
< 80 
32-bit ARM Cortex-M3 microcontroller
=
x1
S
S
, C
L
C L
R S
x2
External load
capacitors C
18 pF, 18 pF
39 pF, 39 pF
57 pF, 57 pF
18 pF, 18 pF
39 pF, 39 pF
57 pF, 57 pF
18 pF, 18 pF
39 pF, 39 pF
18 pF, 18 pF
External load
capacitors C
18 pF, 18 pF
39 pF, 39 pF
18 pF, 18 pF
39 pF, 39 pF
002aaf424
, and C
© NXP B.V. 2011. All rights reserved.
C P
x3
in case of
X1
X1
/C
,
69 of 82
CX2
X2