LPC1111 datasheet(49/59 Pages) NXP

49 / 59 page

LPC1111_12_13_14_1

All information provided in this document is subject to legal disclaimers.

Product data sheet

Rev. 01 — 16 April 2010

49 of 59

NXP Semiconductors

LPC1111/12/13/14

32-bit ARM Cortex-M0 microcontroller

11.3 XTAL Printed Circuit Board (PCB) layout guidelines

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 Cx1, Cx2, and Cx3 in case of

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

Fig 25. Oscillator modes and models: oscillation mode of operation and external crystal

model used for CX1/CX2 evaluation

Table 17.

Recommended values for CX1/CX2 in oscillation mode (crystal and external

components parameters) low frequency mode

Fundamental oscillation

frequency FOSC

Crystal load

capacitance CL

Maximum crystal

series resistance RS

External load

capacitors CX1, CX2

1 MHz - 5 MHz

10 pF

< 300

18 pF, 18 pF

20 pF

< 300

39 pF, 39 pF

30 pF

< 300

57 pF, 57 pF

5 MHz - 10 MHz

10 pF

< 300

18 pF, 18 pF

20 pF

< 200

39 pF, 39 pF

30 pF

< 100

57 pF, 57 pF

10 MHz - 15 MHz

10 pF

< 160

18 pF, 18 pF

20 pF

< 60

39 pF, 39 pF

15 MHz - 20 MHz

10 pF

< 80

18 pF, 18 pF

Table 18.

Recommended values for CX1/CX2 in oscillation mode (crystal and external

components parameters) high frequency mode

Fundamental oscillation

frequency FOSC

Crystal load

capacitance CL

Maximum crystal

series resistance RS

External load

capacitors CX1, CX2

15 MHz - 20 MHz

10 pF

< 180

18 pF, 18 pF

20 pF

< 100

39 pF, 39 pF

20 MHz - 25 MHz

10 pF

< 160

18 pF, 18 pF

20 pF

< 80

39 pF, 39 pF

002aaf424

LPC1xxx

XTALIN

XTALOUT

CX2

CX1

XTAL

LPC1111 Datasheet(PDF) 49 Page - NXP Semiconductors

LPC1111 Datasheet(HTML) 49 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59

Datasheet Download

Link URL