OLIMEX© 2015
A10-OLinuXino-LIME 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 also briefly discussed.
5.1 Reset
The board has hardware reset controlled by the AXP209 power system management IC.
It is a good practice to perform software reset of the board. Performing reset by disconnecting the
power supply might lead to software corruption of the operating system of choice.
5.2 Clocks
25 MHz quartz crystal Q1 is connected to pins X1 and X2 of the RTL8201CP Ethernet controller.
32 768 Hz (RTC) quartz crystal Q2 is found at pins F1 and F2 of the A10 microcontroller.
24 MHz quartz crystal Q3 is found at pins N22 and N23 of the A10 microcontroller.
5.3 Power supply circuit
The power supply is handled mainly by AXP209 power management system, an Allwinner chip that
goes together with the A10 processor. It is mounted on the board but since it is relatively hard to
find we also sell it separately.
The power supply circuit of A10-OLinuXino-LIME requires input supply of 5V. The minimum
wattage is 2.5W, and this threshold may raise if using a lot of devices on the USB-HOST (via
external hub), a lot of GPIOs or you have a display connected to the LCD_CON or a hard disk
powered from the 5V_SATA_PWR connector. If a discharged Li-Po battery is connected to the
respective connector the power consumption of the whole LIME board might rise enormously, since
the built-in battery charger would attempt to recharge it.
For more info on how to power the board refer to chapter “2.3 Powering the board”.
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