NXP Semiconductors LPC5411 Series

LPC5411x All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2018. All rights reserved.
Product data sheet Rev. 2.1 — 9 May 2018 86 of 105
NXP Semiconductors
LPC5411x
32-bit ARM Cortex-M4/M0+ microcontroller
13. Application information
13.1 Start-up behavior
Figure 30 shows the start-up timing after reset. The FRO 12 MHz oscillator provides the
default clock at Reset and provides a clean system clock shortly after the supply pins
reach operating voltage.
13.2 Standard I/O pin configuration
Figure 31 shows the possible pin modes for standard I/O pins:
• Digital output driver: enabled/disabled.
• Digital input: Pull-up enabled/disabled.
• Digital input: Pull-down enabled/disabled.
Fig 30. Start-up timing
Table 41. Typical start-up timing parameters
Parameter Description Value
t
a
FRO start time  20 s
t
b
Internal reset de-asserted 151 s
t
c
Legacy image 931 s
Single image without CRC 904
Dual image without CRC 952
aaa-023995
valid threshold
= 1.62 V
processor status
V
DD
FRO status
internal reset
GND
boot time
user code
boot code
execution
finishes;
user code starts
FRO
starts
supply ramp-up
time
t
b
µst
a
µs
t
c
µs