User manual

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SAM4S-WPIR-RD [USER GUIDE]
42060A–ATARM–12/2012
4.2.2 Clock Circuitry
The board includes 2 clock sources:
 One 12 MHz Crystal for Internal Clock (Y2)
 One 32.768 kHz Crystal for RTC Clock (Y1)
4.2.3 Reset Circuitry
The reset sources for the board are:
 Power on reset
 JTAG reset from an in-circuit emulator (JTAG interface is equipped on the board)
4.2.4 Push Button Switches
 User interface (BP1)
4.2.5 Power Supplies
The Board is driven by 5V input power rail from USB cable or 3 x AAA battery.
The Board embeds all the necessary power rails required for the microcontroller
Table 4-1 summarizes the power specifications.
Table 4-1. Power Rails Associated with the Systems
Nominal Name Powers Component
3.0V VDDIO Partial Peripheral I/O lines on board
3.0V +3V_PERIPH SRAM and image sensor on board
3.0V +3V_LCD LCD and backlight driver on board
1.2V VDDPLL the PLL cell From SAM4S internal LDO
1.2V VDDCORE
the core, including the processor, the
embedded memories and the peripherals
From SAM4S internal LDO
3.0V ADVREF analog on board