OLIMEX© 2015
IMX233-OLinuXino-MAXI user's manual
CHAPTER 5: CONTROL CIRCUITY
5. Introduction to the chapter
Here you can find information about reset circuit and quartz crystals locations, the power supply
circuit is discussed.
5.1 Reset
OLinuXino's reset circuit includes R9 (47KΩ), R10 (47 Ω), T1, T2, Q1 and a RESET button. The
RESET is specific for the fact that it is accomplished when the quartz is disconnected using 3.3V
and the transistors T1 and T2.
5.2 Clocks
24 MHz quartz crystal Q1 is connected to pins 121 and 122 of the iMX233 processor.
25 MHz quartz crystal Q2 is found at pins 60 and 61 of the Ethernet controller – LAN9512-JZX.
5.3 Power supply circuit
The power supply circuit of OLinuXino-MAXI allows flexible input supply from 6V to 16V direct
current. This means a wide range of power supplies, adapters, converters are applicable. The
maximum amperage recommended is 1A by default (0.250mA if 3.3VIO_E is closed – read below).
All measures below are taken at 10V external supply.
If measuring the current consumption it should be around 0.06A before initializing all the
peripherals. The consumption raises to 0.12A without LAN and USB hosts initialized and Linux
running. The consumption goes up 0.15A with the Linux running when LAN and both USB hosts
initialized.
If you have a standard USB flash drive attached to a USB host, Linux and LAN running the typical
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