ATTINY20-XU Atmel, ATTINY20-XU Datasheet - Page 164

• Manufacturer Part Number: ATTINY20-XU
• Description: MCU AVR 2KB FLASH 12MHZ 14TSSOP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY20-XU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 12
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Processor Series: ATtiny
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: SPI, TWI
• Maximum Clock Frequency: 12 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

19.3
19.3.1
164
Non-Volatile Memories
ATtiny20
Non-Volatile Memory Lock Bits
The ATtiny20 has the following, embedded NVM:
The ATtiny20 provides two Lock Bits, as shown in
Table 19-1.
The Lock Bits can be left unprogrammed ("1") or can be programmed ("0") to obtain the addi-
tional security shown in
command, only.
Table 19-2.
Notes:
• Non-Volatile Memory Lock Bits
• Flash memory with four separate sections
Lock Mode
Lock Bit
NVLB2
NVLB1
1
2
3
1. Program the configuration section bits before programming NVLB1 and NVLB2.
2. "1" means unprogrammed, "0" means programmed
Memory Lock Bits
Lock Bit Byte
Lock Bit Protection Modes
NVLB2
Bit No
1
1
0
7
6
5
4
3
2
1
0
(2)
Table
(1)
Description
Non-Volatile Lock Bit
Non-Volatile Lock Bit
NVLB1
19-2. Lock Bits can be erased to "1" with the Chip Erase
1
0
0
(2)
Protection Type
No Memory Lock feature Enabled
Further Programming of the Flash memory is disabled in
the external programming mode. The configuration
section bits are locked in the external programming
mode
Further programming and verification of the flash is
disabled in the external programming mode. The
configuration section bits are locked in the external
programming mode
Table
19-1.
1 (unprogrammed)
1 (unprogrammed)
Default Value
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
8235B–AVR–04/11