Datasheet

LPC1311_13_42_43 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2012. All rights reserved.
Product data sheet Rev. 5 — 6 June 2012 59 of 74
NXP Semiconductors
LPC1311/13/42/43
32-bit ARM Cortex-M3 microcontroller
11. Application information
11.1 Suggested USB interface solutions (LPC1342/43 only)
11.2 XTAL input
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
i
= 100 pF. To limit the input voltage to the specified range, choose an additional
capacitor to ground C
g
which attenuates the input voltage by a factor C
i
/(C
i
+ C
g
). In slave
mode, a minimum of 200 mV(RMS) is needed.
Fig 32. LPC1342/43 USB interface on a self-powered device
LPC134x
USB-B
connector
USB_DP
USB_CONNECT
soft-connect switch
USB_DM
USB_VBUS
V
SS
V
DD
R1
1.5 kΩ
R
S
= 33 Ω
002aae608
R
S
= 33 Ω
Fig 33. LPC1342/43 USB interface on a bus-powered device
LPC134x
V
DD
R1
1.5 kΩ
002aae609
USB-B
connector
USB_DP
USB_DM
USB_VBUS
V
SS
R
S
= 33 Ω
R
S
= 33 Ω