LPC2387FBD100 NXP Semiconductors, LPC2387FBD100 Datasheet - Page 54

• Manufacturer Part Number: LPC2387FBD100
• Description: The LPC2387 is an ARM7 microcontroller for embedded applications featuring a high level of integration and low power consumption at frequencies of 72 MHz
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LPC2387
Product data sheet
Fig 21. LPC2387 USB device port configuration
14.2 Crystal oscillator XTAL input and component selection
LPC2387
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
slave mode, a minimum of 200 mV (RMS) is needed.
In slave mode the input clock signal should be coupled by means of a capacitor of 100 pF
(Figure
corresponds to a square wave signal with a signal swing of between 280 mV and 1.4 V.
The XTAL2 pin in this configuration can be left unconnected.
External components and models used in oscillation mode are shown in
Table 15
and the capacitances C
fundamental mode oscillation (the fundamental frequency is represented by L, C
R
not be larger than 7 pF. Parameters F
manufacturer.
Fig 22. Slave mode operation of the on-chip oscillator
i
S
= 100 pF. To limit the input voltage to the specified range, choose an additional
). Capacitance C
USB_UP_LED
USB_CONNECT
USB_D+
USB_D−
V
BUS
22), with an amplitude between 200 mV (RMS) and 1000 mV (RMS). This
and
Table
All information provided in this document is subject to legal disclaimers.
33 Ω
33 Ω
P
16. Since the feedback resistance is integrated on chip, only a crystal
in
g
V
Rev. 5 — 9 January 2012
which attenuates the input voltage by a factor C
Figure 23
X1
DD
and C
V
DD
X2
represents the parallel package capacitance and should
need to be connected externally in case of
OSC
XTAL1
C i
100 pF
LPC2xxx
, C
L
, R
S
002aae718
C g
and C
P
are supplied by the crystal
Single-chip 16-bit/32-bit MCU
V
SS
V
BUS
D+
D−
002aae169
USB-B
connector
LPC2387
i
© NXP B.V. 2012. All rights reserved.
/ (C
Figure 23
i
+ C
g
L
). In
and
and in
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