Power Supply And Management; Uart - Atmel SAM3N-EK User Manual

Evaluation Kit Hardware
Supply Controller). The NRST pin integrates a permanent pull-up resistor of about 100 kOhm to VDDIO.
On the SAM3N-EK board, the NRST signal is connected to the JTAG port.
4.3.5

Power Supply and Management

The SAM3N-EK board is supplied with an external 5V DC block through the J1 socket. It is protected by
a PolyZen diode MN3. The PolyZen protects the board in the case of an incorrect power supply
connection.
The LDO regulator MN4 is used for the 3.3V main supply. It powers all the 3.3V components on the
board.
Figure 4-4.
The SAM3N4/2/1 product series has different types of power supply pins:
VDDIN pin: Power for the internal voltage regulator, ADC, DAC, and analog comparator power
supplies. This voltage ranges from 1.8V to 3.6V.
VDDIO pin: Powers the Peripheral I/O lines, Backup part, 32 kHz crystal oscillator and oscillator pads.
This voltage ranges from 1.62V to 3.6V.
VDDOUT pin: Output of the internal voltage regulator.
VDDCORE pin: Powers the core, including the processor, the embedded memories and the
peripherals. This voltage ranges from 1.62V to 1.95V.
VDDPLL pin: Powers the PLL, the Fast RC and the 3 to 20 MHz oscillators. This voltage ranges from
1.62V to 1.95V.
4.3.6

UART

The Universal Asynchronous Receiver Transmitter features a two-pin UART that can be used for com-
munication and trace purposes. It offers an ideal channel for in-situ programming solutions. This UART
is associated with two PDC channels to reduce the processor time on packet handling.
The two-pin UART (TXD and RXD only) is buffered through an RS232 Transceiver MN8 and brought to
the DB9 male connector J4.
4-4
11080C–ATARM–30-Mar-11
Power Block
J1 J1 MN3 MN3
MP179P 2.1mm MP179P 2.1mm ZEN056V130A24LS ZEN056V130A24LS
1 1 3
2
MN4 MN4
+5V LP38692MP-3.3 LP38692MP-3.3
4
VIN VOUT
1
+ + VEN NC
C27 C27 C28 C28 C29 C29
100nF 100nF 22uF 22uF 10uF 0805 10uF 0805
DGND
SAM3N-EK Development Board User Guide
+3V3
3
2
C25 C25 C26 C26
1uF 1uF 10uF 0805 10uF 0805