LPC11U23FBD48 NXP Semiconductors, LPC11U23FBD48 Datasheet - Page 53

• Manufacturer Part Number: LPC11U23FBD48
• Description: The LPC11U23FBD48 is a ARM Cortex-M0 based, low-cost 32-bit MCU, designed for 8/16-bit microcontroller applications, offering performance, low power, simple instruction set and memory addressing together with reduced code size compared to existing 8/
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC11U2X
Product data sheet
11.3 XTAL Printed-Circuit Board (PCB) layout guidelines
Table 17.
Table 18.
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
Follow these guidelines for PCB layout:
•
•
•
•
•
Connect the crystal on the PCB as close as possible to the oscillator input and output
pins of the chip.
Take care that the load capacitors C
use have a common ground plane.
Connect the external components to the ground plain.
To keep parasitics and the noise coupled in via the PCB as small as possible, keep
loops as small as possible.
Choose smaller values of 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.
Rev. 2 — 13 January 2012
Crystal load
capacitance C
10 pF
20 pF
30 pF
10 pF
20 pF
10 pF
Crystal load
capacitance C
10 pF
20 pF
10 pF
20 pF
x1
and C
X1
X1
/C
/C
x1
L
L
x2
X2
X2
, C
if parasitics of the PCB layout increase.
in oscillation mode (crystal and external
in oscillation mode (crystal and external
x2
Maximum crystal
series resistance R
< 300 
< 200 
< 100 
< 160 
< 60 
< 80 
Maximum crystal
series resistance R
< 180 
< 100 
< 160 
< 80 
, and C
32-bit ARM Cortex-M0 microcontroller
x3
in case of third overtone crystal
S
S
LPC11U2x
External load
capacitors C
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
© NXP B.V. 2012. All rights reserved.
X1
X1
, C
, C
53 of 70
X2
X2