NXP Semiconductors
LPC2921/2923/2925
ARM9 microcontroller with CAN, LIN, and USB
NXP B.V. 2010.
All rights reserved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: salesaddresses@nxp.com
Date of release: 14 April 2010
Document identifier: LPC2921_23_25_3
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
6.15
Power, Clock, and Reset control SubSystem
(PCRSS). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Clock description . . . . . . . . . . . . . . . . . . . . . . 41
Clock Generation Unit (CGU0). . . . . . . . . . . . 42
6.15.2.1 Functional description. . . . . . . . . . . . . . . . . . . 42
6.15.2.2 PLL functional description . . . . . . . . . . . . . . . 45
6.15.2.3 Pin description . . . . . . . . . . . . . . . . . . . . . . . . 46
6.15.3
Clock generation for USB (CGU1) . . . . . . . . . 47
6.15.3.1 Pin description . . . . . . . . . . . . . . . . . . . . . . . . 47
6.15.4
Reset Generation Unit (RGU). . . . . . . . . . . . . 47
6.15.4.1 Functional description. . . . . . . . . . . . . . . . . . . 48
6.15.4.2 Pin description . . . . . . . . . . . . . . . . . . . . . . . . 48
6.15.5
Power Management Unit (PMU). . . . . . . . . . . 49
6.15.5.1 Functional description. . . . . . . . . . . . . . . . . . . 49
6.16
Vectored interrupt controller . . . . . . . . . . . . . . 51
6.16.1
Functional description. . . . . . . . . . . . . . . . . . . 51
6.16.2
Clock description . . . . . . . . . . . . . . . . . . . . . . 52
7
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 53
8
Static characteristics. . . . . . . . . . . . . . . . . . . . 55
8.1
Power consumption . . . . . . . . . . . . . . . . . . . . 60
8.2
Electrical pin characteristics . . . . . . . . . . . . . . 61
9
Dynamic characteristics . . . . . . . . . . . . . . . . . 64
9.1
Dynamic characteristics: I/O and CLK_OUT
pins, internal clock, oscillators, PLL, and
CAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
9.2
USB interface . . . . . . . . . . . . . . . . . . . . . . . . . 66
9.3
Dynamic characteristics: I
2
C-bus interface. . . 67
9.4
Dynamic characteristics: SPI . . . . . . . . . . . . . 68
9.5
Dynamic characteristics: flash memory and
EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
9.6
Dynamic characteristics: ADC1/2 . . . . . . . . . 70
10
Application information. . . . . . . . . . . . . . . . . . 70
10.1
Operating frequency selection . . . . . . . . . . . . 70
10.2
Suggested USB interface solutions . . . . . . . . 71
10.3
SPI signal forms . . . . . . . . . . . . . . . . . . . . . . . 72
10.4
XIN_OSC input. . . . . . . . . . . . . . . . . . . . . . . . 74
10.5
XIN_OSC Printed Circuit Board (PCB)
layout guidelines. . . . . . . . . . . . . . . . . . . . . . . 74
11
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 75
12
Soldering of SMD packages . . . . . . . . . . . . . . 76
12.1
Introduction to soldering . . . . . . . . . . . . . . . . . 76
12.2
Wave and reflow soldering . . . . . . . . . . . . . . . 76
12.3
Wave soldering. . . . . . . . . . . . . . . . . . . . . . . . 76
12.4
Reflow soldering. . . . . . . . . . . . . . . . . . . . . . . 77
13
Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . 79
14
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
15
Revision history. . . . . . . . . . . . . . . . . . . . . . . . 80
16
Legal information. . . . . . . . . . . . . . . . . . . . . . . 81
6.15.1
6.15.2
16.1
16.2
16.3
16.4
17
18
Data sheet status. . . . . . . . . . . . . . . . . . . . . . 81
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Contact information . . . . . . . . . . . . . . . . . . . . 82
Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83