Datasheet

LPC11U1X All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 2.2 — 11 March 2014 23 of 72
NXP Semiconductors
LPC11U1x
32-bit ARM Cortex-M0 microcontroller
7.16 Clocking and power control
7.16.1 Integrated oscillators
The LPC11U1x include three independent oscillators. These are the system oscillator, the
Internal RC oscillator (IRC), and the watchdog oscillator. Each oscillator can be used for
more than one purpose as required in a particular application.
Following reset, the LPC11U1x will operate from the internal RC oscillator until switched
by software. This allows systems to operate without any external crystal and the
bootloader code to operate at a known frequency.
See Figure 6
for an overview of the LPC11U1x clock generation.