参数资料
| 型号： | 71M6521FE-DB |
| 厂商： | Maxim Integrated Products |
| 文件页数： | 64/107页 |
| 文件大小： | 0K |
| 描述： | BOARD DEMO FOR 71M6521FE |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 1 |
| 主要目的： | 电源管理，电度表/功率表 |
| 嵌入式： | 否 |
| 已用 IC / 零件： | 71M6521 |
| 已供物品： | 2 个板，线缆，CD，电源 |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页当前第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页
71M6521DE/DH/FE Data Sheet
Temperature Compensation and Mains Frequency Stabilization for the RTC
The flexibility provided by the MPU allows for compensation of the RTC using the substrate temperature. To achieve
this, the crystal has to be characterized over temperature and the three coefficients Y_CAL , Y_CALC , and Y_CAL_C2
have to be calculated. Provided the IC substrate temperatures tracks the crystal temperature the coefficients can be
used in the MPU firmware to trigger occasional corrections of the RTC seconds count, using the RTC_DEC_SEC or
RTC_INC_SEC registers in I/O RAM.
Deviation from
Nominal
Temperature [°C]
+50
+25
0
-25
-50
Measured
Frequency [Hz]
32767.98
32768.28
32768.38
32768.08
32767.58
Deviation from
Nominal
Frequency [PPM]
-0.61
8.545
11.597
2.441
-12.817
Table 63: Frequency over Temperature
The values show that even at nominal temperature (the temperature at which the chip was calibrated for energy), the
deviation from the ideal crystal frequency is 11.6 PPM, resulting in about one second inaccuracy per day, i.e. more
than some standards allow. As Figure 32 shows, even a constant compensation would not bring much improvement,
since the temperature characteristics of the crystal are a mix of constant, linear, and quadratic effects.
32768.5
32768.4
32768.3
32768.2
32768.1
32768
32767.9
32767.8
32767.7
32767.6
32767.5
-50
-25
0
25
50
Figure 32: Crystal Frequency over Temperature
One method to correct the temperature characteristics of the crystal is to obtain coefficients from the curve in Figure
32 by curve-fitting the PPM deviations. A fairly close curve fit is achieved with the coefficients a = 10.89, b = 0.122,
f = f nom ? ? 1 +
c ?
10 6 ?
?
?
a
10 6
+ T
b
10 6
+ T 2
?
When applying the inverted coefficients, a curve (see Figure 33) will result that effectively neutralizes the original
crystal characteristics.
Page: 64 of 107
Rev 3
相关PDF资料 |
PDF描述 |
|---|---|
| 71M6531F-DB | BOARD DEMO 71M6531F |
| 71M6533-DB | BOARD DEMO 71M6533 |
| 71M6534H-DB | BOARD DEMO 71M6534H |
| 71M6541F-DB | DEMO BOARD 71M6541F |
| 71M6543F-DB-CT | DEMO BOARD 71M6543F-DB-CT |
相关代理商/技术参数 |
参数描述 |
|---|---|
| 71M6521FE-IGT | 制造商:Maxim Integrated Products 功能描述:Metering Systems on a Chip - SoC Residential Energy Meter IC |
| 71M6521FE-IGT/F | 功能描述:计量片上系统 - SoC Residential Energy Meter IC RoHS:否 制造商:Maxim Integrated 核心:80515 MPU 处理器系列:71M6511 类型:Metering SoC 最大时钟频率:70 Hz 程序存储器大小:64 KB 数据 RAM 大小:7 KB 接口类型:UART 可编程输入/输出端数量:12 片上 ADC: 安装风格:SMD/SMT 封装 / 箱体:LQFP-64 封装:Reel |
| 71M6521FE-IGT/F1 | 功能描述:计量片上系统 - SoC RoHS:否 制造商:Maxim Integrated 核心:80515 MPU 处理器系列:71M6511 类型:Metering SoC 最大时钟频率:70 Hz 程序存储器大小:64 KB 数据 RAM 大小:7 KB 接口类型:UART 可编程输入/输出端数量:12 片上 ADC: 安装风格:SMD/SMT 封装 / 箱体:LQFP-64 封装:Reel |
| 71M6521FE-IGTR | 制造商:Maxim Integrated Products 功能描述:Metering Systems on a Chip - SoC Residential Energy Meter IC |
| 71M6521FE-IGTR/F | 功能描述:计量片上系统 - SoC Residential Energy Meter IC RoHS:否 制造商:Maxim Integrated 核心:80515 MPU 处理器系列:71M6511 类型:Metering SoC 最大时钟频率:70 Hz 程序存储器大小:64 KB 数据 RAM 大小:7 KB 接口类型:UART 可编程输入/输出端数量:12 片上 ADC: 安装风格:SMD/SMT 封装 / 箱体:LQFP-64 封装:Reel |
发布紧急采购，3分钟左右您将得到回复。