MCB1114 Keil, MCB1114 Datasheet - Page 45

• Manufacturer Part Number: MCB1114
• Description: BOARD EVALUATION FOR NXP LPC1114
• Manufacturer: Keil

Specifications of MCB1114

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

NXP Semiconductors
11. Application information
LPC1111_12_13_14_0
Objective data sheet
11.1 XTAL input
11.2 XTAL Printed Circuit Board (PCB) layout guidelines
11.3 Standard I/O pad configuration
The input voltage to the on-chip oscillators is limited to 1.8 V. If the oscillator is driven by a
clock in slave mode, it is recommended that the input be coupled through a capacitor with
C
capacitor to ground C
mode, a minimum of 200 mV(RMS) is needed.
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
order to keep the noise coupled in via the PCB as small as possible. Also parasitics
should stay as small as possible. Values of C
accordingly to the increase in parasitics of the PCB layout.
Figure 24
resistors (R
port pin is input with R
LPC11xx user manual.
Fig 23. Slave mode operation of the on-chip oscillator
i
= 100 pF. To limit the input voltage to the specified range, choose an additional
shows the possible pin modes for standard I/O pins. The pull-up and pull-down
pu
and R
Rev. 00.11 — 13 November 2009
pd
g
pu
) can be enabled or disabled. The default value for each standard
which attenuates the input voltage by a factor C
enabled. For details on pin modes and hysteresis control, see the
XTALIN
LPC1xxx
C i
100 pF
x1
and C
002aae788
C g
LPC1111/12/13/14
x2
should be chosen smaller
x1
,C
x2
, and C
i
/(C
© NXP B.V. 2009. All rights reserved.
i
+ C
x3
g
). In slave
in case of
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