ATtiny25 Automotive Atmel Corporation, ATtiny25 Automotive Datasheet - Page 15

• Manufacturer Part Number: ATtiny25 Automotive
• Manufacturer: Atmel Corporation

Specifications of ATtiny25 Automotive

• Flash (kbytes): 2 Kbytes
• Pin Count: 8
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 4
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 6
• Ext Interrupts: 6
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 4
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 0.12
• Eeprom (bytes): 128
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 125
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 5
• Pwm Channels: 6
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

5.2.1
5.3
5.3.1
7598H–AVR–07/09
EEPROM Data Memory
Data Memory Access Times
EEPROM Read/Write Access
This section describes the general access timing concepts for internal memory access. The
internal data SRAM access is performed in two clk
Figure 5-3.
The ATtiny25/45/85 contains 128/256/512 bytes of data EEPROM memory. It is organized as a
separate data space, in which single bytes can be read and written. The EEPROM has an
endurance of at least 100,000 write/erase cycles. The access between the EEPROM and the
CPU is described in the following, specifying the EEPROM Address Registers, the EEPROM
Data Register, and the EEPROM Control Register. For a detailed description of Serial data
downloading to the EEPROM, see
The EEPROM Access Registers are accessible in the I/O space.
The write access times for the EEPROM are given in
lets the user software detect when the next byte can be written. If the user code contains instruc-
tions that write the EEPROM, some precautions must be taken. In heavily filtered power
supplies, V
period of time to run at a voltage lower than specified as minimum for the clock frequency used.
See
situations.
In order to prevent unintentional EEPROM writes, a specific write procedure must be followed.
Refer to
details on this.
When the EEPROM is read, the CPU is halted for four clock cycles before the next instruction is
executed. When the EEPROM is written, the CPU is halted for two clock cycles before the next
instruction is executed.
“Preventing EEPROM Corruption” on page 20
“Atomic Byte Programming” on page 18
CC
is likely to rise or fall slowly on Power-up/down. This causes the device for some
On-chip Data SRAM Access Cycles
Address
clk
Data
Data
WR
CPU
RD
Compute Address
T1
Memory Access Instruction
page
138.
Address valid
and
CPU
for details on how to avoid problems in these
T2
Table
cycles as described in
“Split Byte Programming” on page 18
5-1. A self-timing function, however,
Next Instruction
ATtiny25/45/85
T3
Figure
5-3.
for
15