参数资料
型号: ATMEGA645-16MUR
厂商: Atmel
文件页数: 13/85页
文件大小: 0K
描述: MCU AVR 64KB FLASH 16MHZ 64QFN
产品培训模块: megaAVR Introduction
标准包装: 4,000
系列: AVR® ATmega
核心处理器: AVR
芯体尺寸: 8-位
速度: 16MHz
连通性: SPI,UART/USART,USI
外围设备: 欠压检测/复位,POR,PWM,WDT
输入/输出数: 53
程序存储器容量: 64KB(32K x 16)
程序存储器类型: 闪存
EEPROM 大小: 2K x 8
RAM 容量: 4K x 8
电压 - 电源 (Vcc/Vdd): 2.7 V ~ 5.5 V
数据转换器: A/D 8x10b
振荡器型: 内部
工作温度: -40°C ~ 85°C
封装/外壳: 64-VFQFN 裸露焊盘
包装: 带卷 (TR)
其它名称: ATMEGA645-16MUR-ND
ATMEGA645-16MURTR
20
2570N–AVR–05/11
ATmega325/3250/645/6450
Figure 8-3.
On-chip Data SRAM Access Cycles
8.3
EEPROM Data Memory
The Atmel ATmega325/3250/645/6450 contains 1/2K 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 Regis-
ters, the EEPROM Data Register, and the EEPROM Control Register.
For a detailed description of SPI, JTAG and Parallel data downloading to the EEPROM, see
page 280, page 284, and page 268 respectively.
8.3.1
EEPROM Read/Write Access
The EEPROM Access Registers are accessible in the I/O space.
The write access time for the EEPROM is given in Table 8-1. A self-timing function, however,
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
CC is likely to rise or fall slowly on power-up/down. This causes the device for some
period of time to run at a voltage lower than specified as minimum for the clock frequency used.
See “Preventing EEPROM Corruption” on page 21. for details on how to avoid problems in these
situations.
In order to prevent unintentional EEPROM writes, a specific write procedure must be followed.
Refer to the description of the EEPROM Control Register for 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.
8.3.2
EEPROM Write During Power-down Sleep Mode
When entering Power-down sleep mode while an EEPROM write operation is active, the
EEPROM write operation will continue, and will complete before the Write Access time has
passed. However, when the write operation is completed, the clock continues running, and as a
clk
WR
RD
Data
Address
Address valid
T1
T2
T3
Compute Address
Read
Wr
ite
CPU
Memory Access Instruction
Next Instruction
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相关代理商/技术参数
参数描述
ATMEGA645A-AU 功能描述:8位微控制器 -MCU AVR 64KB FLSH 2KB EE 4KB SRAM-20MHz, IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA645A-AUR 功能描述:8位微控制器 -MCU AVR 64KB FLSH 2KB EE 4KB SRAM-20MHz, IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA645A-MU 功能描述:8位微控制器 -MCU AVR 64KB FLSH 2KB EE 4KB SRAM-20MHz, IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA645A-MUR 功能描述:8位微控制器 -MCU AVR 64KB FLSH 2KB EE 4KB SRAM-20MHz, IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ATMEGA645P-AU 功能描述:8位微控制器 -MCU AVR 64KB FLSH 2KB EE 4KB SRAM-16MHz, IND RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT