SAM7SE256 Atmel Corporation, SAM7SE256 Datasheet - Page 13

• Manufacturer Part Number: SAM7SE256
• Manufacturer: Atmel Corporation

Specifications of SAM7SE256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 48 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 88
• Ext Interrupts: 88
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

5. Power Considerations
5.1
5.2
5.3
6222F–ATARM–14-Jan-11
Power Supplies
Power Consumption
Voltage Regulator
The SAM7SE512/256/32 has six types of power supply pins and integrates a voltage regulator,
allowing the device to be supplied with only one voltage. The six power supply pin types are:
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.
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 SAM7SE512/256/32 has a static current of less than 60 µA on VDDCORE at 25°C, includ-
ing the RC oscillator, the voltage regulator and the power-on reset when the brownout detector
is deactivated. Activating the brownout detector adds 20 µA static current.
The dynamic power consumption on VDDCORE is less than 80 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 SAM7SE512/256/32 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 20 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:
• 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; two voltage ranges are supported:
• VDDFLASH pin. It powers the USB transceivers and a part of the Flash. It is required for the
• 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
• One external 470 pF (or 1 nF) NPO capacitor should be connected between VDDOUT and
3.3V nominal.
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.
GND as close to the chip as possible.
– from 3.0V to 3.6V, 3.3V nominal
– or from 1.65V to 1.95V, 1.8V nominal.
SAM7SE512/256/32
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