AT91SAM7SE256 ATMEL [ATMEL Corporation], AT91SAM7SE256 Datasheet - Page 14

• Manufacturer Part Number: AT91SAM7SE256
• Description: Product Description
• Manufacturer: ATMEL [ATMEL Corporation]

5.4
14
Typical Powering Schematics
AT91SAM7SE512/256/32 Preliminary
Adequate input supply decoupling is mandatory for VDDIN in order to improve startup stability
and reduce source voltage drop. The input decoupling capacitor should be placed close to the
chip. For example, two capacitors can be used in parallel: 100 nF NPO and 4.7 µF X7R.
The AT91SAM7SE512/256/32 supports a 3.3V single supply mode. The internal regulator input
connected to the 3.3V source and its output feeds VDDCORE and the VDDPLL.
shows the power schematics to be used for USB bus-powered systems.
Figure 5-1.
• One external 470 pF (or 1 nF) NPO capacitor should be connected between VDDOUT and
• One external 2.2 µF (or 3.3 µF) X7R capacitor should be connected between VDDOUT and
GND as close to the chip as possible.
GND.
3.3V System Single Power Supply Schematic
from 4.5V (USB)
Power Source
ranges
to 18V
DC/DC Converter
3.3V
VDDFLASH
VDDIO
VDDIN
VDDOUT
VDDCORE
VDDPLL
Regulator
Voltage
6222ES–ATARM–15-Dec-09
Figure 5-1