User`s manual

Am186™CC Microcontroller Router Reference Design User’s Manual
2-7
Power Supply
The Am186CC microcontroller router reference design is powered by a universal
power supply that converts 100–200 V
AC
power to 12 V
DC
, 2.5 A. The 12 V enters
the Am186CC microcontroller router reference design through a 5.5-mm barrel
connector, where the center post is V
CC
and the outer ring is GND. From the
12-V
DC
input, the on-board power supply provides 5 V, 3.3 V, –5 V, –24 V,
and –70 V. The following sections provide details about the power supply.
5V @ 3A
NOTE: See sheet 11 in the schematics for power supply circuits.
A MIC4576 (U44 at location D-7) voltage regulator generates 5 V from the 12-V
source. The voltage regulator provides power to most of the components in the
reference design, including the DRAM, SRAM, and Flash memory components;
the DCE and High-Speed UART transceiver; the HDLC clock generator; and the
3.3-V low drop out (LDO) regulator (MIC5209, U32 at location D-8). This power
supply is also routed to the TIP connector.
3.3 V @ 500 mA
NOTE: See sheet 11 in the schematics for power supply circuits.
The 3.3-V LDO regulator, MIC5209 (U32 at location D-8), generates 3.3 V from
the 5-V source. This power supply provides power to the Am186CC
microcontroller and the USB detect circuitry.
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