HP LaserJet Enterprise M552 - Page 9

Table of contents
1 Theory of operation ....................................................................................................................................... 1
For additional service and support ........................................................................................................................ 2
Basic operation ...................................................................................................................................................... 3
Sequence of operation ........................................................................................................................ 5
Formatter-control system ..................................................................................................................................... 7
Sleep mode .......................................................................................................................................... 7
Printer job language (PJL) ................................................................................................................... 8
Printer management language (PML) ................................................................................................. 8
Control panel ....................................................................................................................................... 8
Easy-access USB port .......................................................................................................................... 9
Wireless ............................................................................................................................................... 9
Near eld communication (NFC) .......................................................................................................... 9
CPU ....................................................................................................................................................... 9
Input/output (I/O) ................................................................................................................................ 9
Memory ................................................................................................................................................ 9
Firmware ......................................................................................................................... 10
Nonvolatile random access memory (NVRAM) ............................................................... 10
Random access memory (RAM) ...................................................................................... 10
HP Memory Enhancement technology (MEt) .................................................................. 10
Engine-control system ........................................................................................................................................ 11
DC controller ...................................................................................................................................... 12
Motors ............................................................................................................................. 13
Fans ................................................................................................................................. 14
Solenoids ......................................................................................................................... 14
Clutches ........................................................................................................................... 14
Switches .......................................................................................................................... 14
Sensors ........................................................................................................................... 16
Low-voltage power supply ................................................................................................................ 18
Low-voltage power supply voltages description ........................................................... 19
Over-current/over-voltage protection ........................................................................... 19
Sleep mode operation ..................................................................................................... 19
Low-voltage power supply failure detection ................................................................. 20
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