AT91SAM7X512 ATMEL Corporation, AT91SAM7X512 Datasheet - Page 11

• Manufacturer Part Number: AT91SAM7X512
• Description: AT91 ARM Thumb-based Microcontrollers
• Manufacturer: ATMEL Corporation

5. Power Considerations
5.1
5.2
5.3
6120DS–ATARM–03-Oct-06
Power Supplies
Power Consumption
Voltage Regulator
The AT91SAM7X512/256/128 has six types of power supply pins and integrates a voltage regu-
lator, allowing the device to be supplied with only one voltage. The six power supply pin types
are:
No separate ground pins are provided for the different power supplies. Only GND pins are pro-
vided and should be connected as shortly as possible to the system ground plane.
The AT91SAM7X512/256/128 has a static current of less than 60 µA on VDDCORE at 25°C,
including the RC oscillator, the voltage regulator and the power-on reset when the brownout
detector is deactivated. Activating the brownout detector adds 28 µA static current.
The dynamic power consumption on VDDCORE is less than 90 mA at full speed when running
out of the Flash. Under the same conditions, the power consumption on VDDFLASH does not
exceed 10 mA.
The AT91SAM7X512/256/128 embeds a voltage regulator that is managed by the System
Controller.
In Normal Mode, the voltage regulator consumes less than 100 µA static current and draws 100
mA of output current.
The voltage regulator also has a Low-power Mode. In this mode, it consumes less than 25 µA
static current and draws 1 mA of output current.
Adequate output supply decoupling is mandatory for VDDOUT to reduce ripple and avoid oscil-
lations. The best way to achieve this is to use two capacitors in parallel: one external 470 pF (or
1 nF) NPO capacitor should be connected between VDDOUT and GND as close to the chip as
possible. One external 2.2 µF (or 3.3 µF) X7R capacitor should be connected between VDDOUT
and GND.
• VDDIN pin. It powers the voltage regulator and the ADC; voltage ranges from 3.0V to 3.6V,
• VDDOUT pin. It is the output of the 1.8V voltage regulator.
• VDDIO pin. It powers the I/O lines; voltage ranges from 3.0V to 3.6V, 3.3V nominal.
• VDDFLASH pin. It powers the USB transceivers and a part of the Flash and is required for
• VDDCORE pins. They power the logic of the device; voltage ranges from 1.65V to 1.95V,
• VDDPLL pin. It powers the oscillator and the PLL. It can be connected directly to the
3.3V nominal. In order to decrease current consumption, if the voltage regulator and the ADC
are not used, VDDIN, ADVREF, AD4, AD5, AD6 and AD7 should be connected to GND. In
this case, VDDOUT should be left unconnected.
the Flash to operate correctly; voltage ranges from 3.0V to 3.6V, 3.3V nominal.
1.8V typical. It can be connected to the VDDOUT pin with decoupling capacitor. VDDCORE
is required for the device, including its embedded Flash, to operate correctly.
VDDOUT pin.
AT91SAM7X512/256/128 Preliminary Summary
11