ATtiny25 Automotive Atmel Corporation, ATtiny25 Automotive Datasheet - Page 52

• 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

10.2.6
10.3
52
Alternate Port Functions
ATtiny25/45/85
Unconnected Pins
If some pins are unused, it is recommended to ensure that these pins have a defined level. Even
though most of the digital inputs are disabled in the deep sleep modes as described above, float-
ing inputs should be avoided to reduce current consumption in all other modes where the digital
inputs are enabled (Reset, Active mode and Idle mode).
The simplest method to ensure a defined level of an unused pin, is to enable the internal pull-up.
In this case, the pull-up will be disabled during reset. If low power consumption during reset is
important, it is recommended to use an external pull-up or pulldown. Connecting unused pins
directly to V
accidentally configured as an output.
Most port pins have alternate functions in addition to being general digital I/Os.
shows how the port pin control signals from the simplified
alternate functions. The overriding signals may not be present in all port pins, but the figure
serves as a generic description applicable to all port pins in the AVR microcontroller family.
Figure 10-5. Alternate Port Functions
PUOExn:
PUOVxn:
DDOExn:
DDOVxn:
PVOExn:
PVOVxn:
DIEOExn: Pxn DIGITAL INPUT-ENABLE OVERRIDE ENABLE
DIEOVxn: Pxn DIGITAL INPUT-ENABLE OVERRIDE VALUE
SLEEP:
PTOExn:
Pxn
CC
Pxn PULL-UP OVERRIDE ENABLE
Pxn PULL-UP OVERRIDE VALUE
Pxn DATA DIRECTION OVERRIDE ENABLE
Pxn DATA DIRECTION OVERRIDE VALUE
Pxn PORT VALUE OVERRIDE ENABLE
Pxn PORT VALUE OVERRIDE VALUE
SLEEP CONTROL
Pxn, PORT TOGGLE OVERRIDE ENABLE
or GND is not recommended, since this may cause excessive currents if the pin is
1
0
1
0
1
0
1
0
PUOExn
PUOVxn
PVOExn
PVOVxn
DIEOExn
DIEOVxn
SLEEP
DDOExn
DDOVxn
(1)
SYNCHRONIZER
D
L
CLR
SET
Q
Q
PUD:
WDx:
RDx:
RRx:
WRx:
RPx:
WPx:
clk
DIxn:
AIOxn:
D
PINxn
CLR
I/O
Q
Q
:
RESET
PORTxn
Q
Q
CLR
D
RESET
Q
Q
DDxn
CLR
WRITE DDRx
WRITE PORTx
PULLUP DISABLE
READ DDRx
READ PORTx REGISTER
READ PORTx PIN
WRITE PINx
I/O CLOCK
DIGITAL INPUT PIN n ON PORTx
ANALOG INPUT/OUTPUT PIN n ON PORTx
D
Figure 10-2
1
0
RRx
clk
PUD
WDx
RDx
DIxn
AIOxn
RPx
I/O
WRx
can be overridden by
PTOExn
WPx
7598H–AVR–07/09
Figure 10-5