AT91SAM7S256D-AU Atmel, AT91SAM7S256D-AU Datasheet - Page 608

• Manufacturer Part Number: AT91SAM7S256D-AU
• Description: ARM Microcontrollers - MCU 256K Flash SRAM 64K ARM based MCU
• Manufacturer: Atmel
• Series: SAM7S256r

Specifications of AT91SAM7S256D-AU

• Rohs: yes
• Core: ARM
• Processor Series: AT91SAM
• Data Bus Width: 16 bit/32 bit
• Maximum Clock Frequency: 55 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 64 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: LQFP-64
• Mounting Style: SMD/SMT
• Interface Type: 2-Wire, I2S, SPI, USART
• Length: 7 mm

40.5.1.10
40.5.1.11
40.5.2
40.5.2.1
40.5.3
40.5.3.1
Do not take into account the EOC of a disabled channel
If “x” and “y” are two successively converted channels and “z” is yet another enabled channel (“z” being neither “x”
nor “y”), reading CDR on channel “z” at the same instant as an end of conversion on channel “y” automatically
clears EOC[x] instead of EOC[z].
None.
If Sleep mode is activated while there is no activity (no conversion is being performed), it will take effect only after
a conversion occurs.
To activate sleep mode as soon as possible, it is recommended to write successively, ADC Mode Register
(SLEEP) then ADC Control Register (START bit field); to start an analog-to-digital conversion, in order put ADC
into sleep mode at the end of this conversion.
The Flash memory access time has been reduced as per the table below:
Set the number of Wait States (FWS) according to the frequency requirements described in this errata.
When PA17, PA18, PA19 or PA20 (the I/O lines multiplexed with the analog inputs) are set as digital inputs with
pull-up disabled, the leakage can be 9 µA in worst case and 90 nA in typical case per I/O when the I/O is set exter-
nally at low level.
Set the I/O to VDDIO by internal or external pull-up.
Flash Wait
State (FWS)
0
1
2
3
Embedded Flash Controller (EFC)
Parallel Input/Output Controller (PIO)
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
ADC: Spurious Clear of EOC Flag
ADC: Sleep Mode
EFC: Embedded Flash Access Time 2
PIO: Leakage on PA17 - PA20
Read
Operations
1 cycle
2 cycles
3 cycles
4 cycles
Maximum Operating
Frequency (MHz)
32
48
55
16
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
608