- 您现在的位置：买卖IC网 > PDF目录20611 > 71M6511H-IGT/F (Maxim Integrated)IC ENERGY METER RESIDENT 64-LQFP PDF资料下载
参数资料
| 型号： | 71M6511H-IGT/F |
| 厂商： | Maxim Integrated |
| 文件页数： | 78/98页 |
| 文件大小： | 0K |
| 描述： | IC ENERGY METER RESIDENT 64-LQFP |
| 产品培训模块： | Lead (SnPb) Finish for COTS Obsolescence Mitigation Program |
| 标准包装： | 160 |
| 系列： | * |
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页当前第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
71M6511/71M6511H
Single-Phase Energy Meter IC
A Maxim Integrated Products Brand
DATA SHEET
NOVEMBER 2010
Temperature Compensation and Mains Frequency Stabilization for the RTC
The accuracy of the RTC depends on the stability of the external crystal. Crystals vary in terms of initial accuracy as well as in
terms of behavior over temperature. The flexibility provided by the MPU allows for compensation of the RTC using the sub-
strate 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.
It is not recommended to measure crystal frequency directly due to the error introduced by the measurement probes. A
practical method to measure the crystal frequency (when installed on the PCB with the 71M6511) is to have a DIO pin toggle
every second, based on the RTC interrupt, with all other interrupts disabled. When this signal is measured with a precision
timer, the crystal frequency can be obtained from the measured time period t (in μs):
f = 32768
10 6 μs
t
Example: Let us assume a crystal characterized by the measurements shown in Table 62. 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.
Deviation from
Nominal
Temperature [°C]
Measured
Frequency [Hz]
Deviation from
Nominal
Frequency [PPM]
+50
+25
0
-25
-50
32767.98
32768.28
32768.38
32768.08
32767.58
-0.61
8.545
11.597
2.441
-12.817
Table 62: Frequency over Temperature
As Figure 29 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 (in commercially available crystals, the constant and quadratic
effects are dominant).
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 29: Crystal Frequency over Temperature
The temperature characteristics of the crystal are obtained from the curve in Figure 29 by curve-fitting the PPM deviations. A
fairly close curve fit is achieved with the coefficients a = 10.89, b = 0.122, and c = –0.00714 (see Figure 30).
Page: 78 of 98
? 2005–2010 Teridian Semiconductor Corporation
V2.7
相关PDF资料 |
PDF描述 |
|---|---|
| GSA06DTKN-S288 | CONN EDGECARD 12POS .125 EXTEND |
| GBC17DRTF | CONN EDGECARD 34POS DIP .100 SLD |
| ISL9307IRTAANFZ-T | IC REG QD BCK/LINEAR SYNC 16TQFN |
| ISL83202IBZT | IC FET DRIVER H-BRIDGE 1A 16SOIC |
| 78M6613-IMR/F/PSP | IC PWR MEASUREMENT 1PH AC 32SQFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| 71M6511H-IGTR | 制造商:Maxim Integrated Products 功能描述:RESID. HI PRECISION METR (1P, .1%) - Tape and Reel |
| 71M6511H-IGTR/F | 功能描述:计量片上系统 - SoC Highly Integrated SoC w/MCU Core 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 |
| 71M6511-IGT | 制造商:TERIDIAN 制造商全称:TERIDIAN 功能描述:Single-Phase Energy Meter IC |
| 71M6511-IGT/F | 功能描述:计量片上系统 - SoC Highly Integrated SoC w/MCU Core 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 |
| 71M6511-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 |
发布紧急采购，3分钟左右您将得到回复。