参数资料
| 型号： | PIC12F1822-I/MF |
| 厂商： | Microchip Technology |
| 文件页数： | 64/109页 |
| 文件大小： | 0K |
| 描述： | IC MCU 8BIT FLASH 8DFN |
| 产品培训模块： | 8-bit PIC® Microcontroller Portfolio |
| 标准包装： | 120 |
| 系列： | PIC® XLP™ 12F |
| 核心处理器： | PIC |
| 芯体尺寸： | 8-位 |
| 速度： | 32MHz |
| 连通性： | I²C，LIN，SPI，UART/USART |
| 外围设备： | 欠压检测/复位，POR，PWM，WDT |
| 输入/输出数： | 6 |
| 程序存储器容量： | 3.5KB（2K x 14） |
| 程序存储器类型： | 闪存 |
| EEPROM 大小： | 256 x 8 |
| RAM 容量： | 128 x 8 |
| 电压 - 电源 (Vcc/Vdd)： | 1.8 V ~ 5.5 V |
| 数据转换器： | A/D 4x10b |
| 振荡器型： | 内部 |
| 工作温度： | -40°C ~ 85°C |
| 封装/外壳： | 8-VDFN 裸露焊盘 |
| 包装： | 管件 |
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249
7674F–AVR–09/09
ATmega164P/324P/644P
21.5.1
Differential Gain Channels
When using differential gain channels, certain aspects of the conversion need to be taken into
consideration. Note that the differential channels should not be used with an AREF < 2V.
Differential conversions are synchronized to the internal clock CK
ADC2 equal to half the ADC
clock. This synchronization is done automatically by the ADC interface in such a way that the
sample-and-hold occurs at a specific phase of CK
ADC2. A conversion initiated by the user (i.e., all
single conversions, and the first free running conversion) when CK
ADC2 is low will take the same
amount of time as a single ended conversion (13 ADC clock cycles from the next prescaled
clock cycle). A conversion initiated by the user when CK
ADC2 is high will take 14 ADC clock
cycles due to the synchronization mechanism. In Free Running mode, a new conversion is initi-
ated immediately after the previous conversion completes, and since CK
ADC2 is high at this time,
all automatically started (i.e., all but the first) free running conversions will take 14 ADC clock
cycles.
The gain stage is optimized for a bandwidth of 4 kHz at all gain settings. Higher frequencies may
be subjected to non-linear amplification. An external low-pass filter should be used if the input
signal contains higher frequency components than the gain stage bandwidth. Note that the ADC
clock frequency is independent of the gain stage bandwidth limitation. For example, the ADC
clock period may be 6 s, allowing a channel to be sampled at 12 kSPS, regardless of the band-
width of this channel.
If differential gain channels are used and conversions are started by Auto Triggering, the ADC
must be switched off between conversions. When Auto Triggering is used, the ADC prescaler is
reset before the conversion is started. Since the gain stage is dependent of a stable ADC clock
prior to the conversion, this conversion will not be valid. By disabling and then re-enabling the
ADC between each conversion (writing ADEN in ADCSRA to “0” then to “1”), only extended con-
versions are performed. The result from the extended conversions will be valid. See “Prescaling
and Conversion Timing” on page 246 for timing details.
21.6
Changing Channel or Reference Selection
The MUXn and REFS1:0 bits in the ADMUX Register are single buffered through a temporary
register to which the CPU has random access. This ensures that the channels and reference
selection only takes place at a safe point during the conversion. The channel and reference
selection is continuously updated until a conversion is started. Once the conversion starts, the
channel and reference selection is locked to ensure a sufficient sampling time for the ADC. Con-
tinuous updating resumes in the last ADC clock cycle before the conversion completes (ADIF in
ADCSRA is set). Note that the conversion starts on the following rising ADC clock edge after
ADSC is written. The user is thus advised not to write new channel or reference selection values
to ADMUX until one ADC clock cycle after ADSC is written.
Table 21-1.
ADC Conversion Time
Condition
Sample & Hold (Cycles
from Start of Conversion)
Conversion Time (Cycles)
First conversion
14.5
25
Normal conversions, single ended
1.5
13
Auto Triggered conversions
2
13.5
Normal conversions, differential
1.5/2.5
13/14
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| PIC12F1822T-E/SN | 制造商:Microchip Technology Inc 功能描述:PIC12F Series 128 B RAM 3.5 kB Flash 8-Bit CMOS Microcontroller - SOIC-8 |
| PIC12F1822T-I/MF | 功能描述:8位微控制器 -MCU 3.5KB 128B RAM 32MHz 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 |
| PIC12F1822T-I/SN | 功能描述:8位微控制器 -MCU 3.5KB 128B RAM 32MHz Int. Osc 6 I/0 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 |
| PIC12F1822T-I/SS | 制造商:MICROCHIP 制造商全称:Microchip Technology 功能描述:8/14-Pin Flash Microcontrollers with nanoWatt XLP Technology |
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