How can I get to Helen center on Financial Street
bus line: Metro Line 3 → Metro Line 4, the whole journey is about 11.1km
1. Take Metro Line 3 from South Changjiang Road, pass 7 stops to Baoshan Road Station
2. Take Metro Line 4, pass 1 stop to hailun Road Station
3. Walk about 280m to Financial Street (hailun) center
No, Helen building is about 700 meters away from the center of Financial Street
8. Ticket issuing form and hotel confirmation form
9. Color of business license shall be stamped with the company's red official seal
10. Color of organization code certificate shall be stamped with the company's red official seal (if three certificates in one are not available)
11. Personal visa application form
12. Copy of house property certificate
13. Copy of vehicle driving license
14 Original tax certificate
15. Old passport (if any)
(must meet the tax payment of more than RMB 3000 per year)
retirees: need to provide a of retirement certificate, students: submit a of student card. In addition to the above information, please provide the original residence permit of Beijing Lingqu within the validity period
[more than three years]
1. Passport: valid for at least half a year from the return journey, more than 2 pages of blank endorsement page (with old passport, the original must be provided)
2. Photos: 2 pieces of 4.5cm * 4.5cm white background color photos (photos must be within half a year, if the passport is applied half a year ago, The photos on the passport can't be the same as those submitted at present.
3. Visa application form and acceptance form (visa application form is not required for the form free package) 4. A of the whole household register
5. A of marriage certificate / divorce certificate
6. Employment certificate: the principal applicant shall provide annual income certificate (annual income shall not be less than 200000). The income certificate should have the exact address, telephone number and fax number of the unit for the consulate to inquire; There are unit name title, official seal, special financial seal
7 Personal tax payment certificate or wage statement (necessary materials): principal applicant who has not been to Japan within three years: provide the original personal tax payment certificate with an annual income of no less than 200000 yuan (annual tax payment of no less than 20490 yuan) or the original bank card statement with corresponding annual income and wage within one year. Principal applicant who has been to Japan within three years: provide the indivial with an annual income of no less than 100000 yuan The original tax payment certificate or the original bank statement showing the corresponding annual income and salary within one year. A of the visa page and the entry-exit seal page of those who have been to Japan within three years. The visa page for visiting Japan is on the old passport, which must be provided
8. Business license with official seal
9. ID card front and back copies
10. Hotel confirmation form and round-trip ticket issuing form
11. Personal information processing consent: please sign. If you have an old passport, please provide it together with retirees: you need to provide a of retirement certificate, Student: submit a of the school certificate or student ID card and the student status verification report of xuexin.com important tips: housewives, children, students, retired and unemployed persons can only apply as accompanying relatives, and the principal applicant must be an in-service person. If you are not in Shanghai, but working or studying in Shanghai, in addition to the above information, please provide the original of your valid residence permit in Shanghai
[more than five years]
1. Original passport
2.45 * 45mm white background color certificate photo
3. CYTS acceptance form
4. Original tax certificate and current statement (more than 97000 yuan for one year tax payment and more than 500000 yuan for the past 12 months)
5. Copy of both sides of ID card
6. Original employment certificate (must be provided, One for each person, with an income of more than 500000 next year)
7. Copy of the whole household registration book
8. Ticket issue form and hotel confirmation form
9. Old passport (if any)
retiree: one of retirement certificate is required, student: one of student card. In addition to the above information, please provide the original residence permit of Beijing Lingqu within the validity period. Important note: housewives, children, students, retired and unemployed persons can only apply as accompanying relatives
specifically, the function of the battery meter is to accurately display the remaining battery state, which is very important for the user's life expectancy management. It's a pity that many domestic machines don't add an independent electricity meter, but simply use the battery's electric performance curve to roughly judge. So many mobile phones will turn off at any time when the display reaches 10% or even 20%, while Apple can turn off at 1% under normal circumstances. However, once there is a problem with the electricity meter itself, it will naturally be in a mess: the battery is clearly still charged, and the electricity meter has "corrected" to inform the main control to shut down and have a rest
then, how does the power meter monitor the power of the equipment? How does it work? Which typical electricity meter chips are mainly used in the market? Let's learn more about it with Xiaobian
how does the electricity meter monitor the power of the equipment< There are three types of coulometers in the current equipment:
1
voltage test method
this is the earliest method used, that is, to obtain the resial capacity by monitoring the open circuit voltage of the battery. This is because there is a definite relationship between the terminal voltage and the resial capacity of the battery, and the resial capacity can be estimated by measuring the terminal voltage of the battery. The limitations of this method are as follows:
1) the relationship between open circuit voltage and capacity is different for batteries proced by different manufacturers
2) only by measuring the open circuit voltage when the battery is no-load can we get relatively accurate results, but most applications need to know the remaining capacity of the battery in operation. At this time, the voltage drop caused by the load current on the internal resistance will affect the accuracy of open circuit voltage measurement. However, the internal resistance of the battery is very discrete, which will become greater with the aging of the battery, so it is very difficult to compensate the error caused by the voltage drop
from the figure below, we can also see that the battery power and voltage are not linear, so this test method is not accurate, and the power measurement accuracy is only more than 20%. Especially when the battery power is less than 50%, the power calculation of mobile phone will become very inaccurate. So the protection of the battery is very limited
to sum up, the method of real-time estimation of battery resial capacity by open circuit voltage can not achieve enough accuracy in practical application, and can only provide a rough reference value. Due to the improvement of all aspects of science and technology, this method is graally eliminated by the mobile phone market. Although there are still some mobile phones with this calculation method, it is no longer the mainstream<
lithium battery discharge curve
2
battery modeling method
this method is based on the battery discharge curve to establish a data table, the data table will indicate the value of electricity under different voltages, this method can effectively improve the accuracy of measurement. But it is not easy to get an accurate data table, because the relationship between voltage and power also involves the temperature, self discharge, aging and other factors of the battery. Only by combining many factors to correct, can we get a more satisfactory measurement
3
coulometer
at present, coulometer is the most widely used calculation method in mobile phones. Coulometer is a device designed to measure the amount of electricity passing through the circuit according to Faraday's law, which is called "coulometer" or "coulometer". In short, an electricity metering chip is connected in series on the protection circuit of the battery, in which an integrated sampling resistor is connected in series. The resistance is used to test the current flowing through the circuit in unit time. If the current changes with time, and different voltage differences are generated after flowing through different currents, the changed current is integrated, that is, ring this period of time, In addition, by cooperating with the battery voltage and temperature, it can greatly rece the impact of battery aging and other factors on the measurement results. This method is used in the iPhone
to get the current capacity of the battery, we can get the final accurate value of the remaining electricity. The coulometer can get the current capacity of the battery through two types of design. One is a / D analog-to-digital conversion, which is usually 12 bit precision. The voltage value is converted to a 12 bit precision hexadecimal number and multiplied by the sampling interval time. The second is the integrated mode. The RC integral circuit is used to obtain the voltage to time integral value, and then the battery capacity is obtained. Finally, the percentage is calculated by dividing the current battery capacity by the rated capacity of the battery, Get the remaining amount of battery power and give it to the software on the mobile phone, and show it to the user through the software
the rated capacity of lithium battery will be lost with the increase of service time. For example, after a 2000 MAH battery is recycled for 100 times, the capacity of the battery itself may be reced to 1800 MAH. If the coulometer keeps the original rated capacity, the calculation of power will be inaccurate, So there is an algorithm to adjust the capacity to the number of times of use in the coulometer, which will adjust the actual rated capacity of the battery according to the number of battery cycles
from the above three methods, we can see that the accuracy of coulomb meter is the highest. It can rece the discharge cut-off voltage of the battery without damaging the battery, and make the maximum use of the battery capacity, especially for the low-voltage system and the battery used for many times. In addition, the warning message of insufficient battery can be sent out with higher accuracy to avoid data loss ring use
working principle of battery energy meter
simplified block diagram of battery energy meter
the battery energy meter continuously integrates the total current flowing into and out of the battery, and takes the net charge obtained by integration as the remaining capacity
the simplified battery meter is shown in the figure above. Where RSNs is m Ω RL is the load resistance. The voltage drop at both ends of RSNs is vs (T) = IO (T) × Rsns The voltage difference vs at both ends of RSNs is continuously detected by the coulometer, which is converted into n-bit digital current (CR) through ADC, and then accumulated at the rate determined by the time base. The m-bit accumulation result is accumulated_ The unit of current (ACR) is VH. Accumulating the quantized vs is equivalent to integrating it, and the result is
battery power
therefore, dividing the ACR value by the resistance value of the current sensing resistance RSNs to obtain the battery capacity in ah (ampere hour). According to the connection mode in Figure 1, Cr is positive and ACR is increasing when charging; CR was negative and ACR decreased ring discharge. The external microcontroller can read Cr and ACR values, and get the real charging and discharging current and electricity value through conversion
the actual electricity meter also includes some control and interface logic, and usually can detect the battery voltage, temperature and other parameters. Some smart meters can automatically complete the correction of battery self discharge, save the battery characteristic curve, and allow users to customize the battery power calculation method
calculation of battery energy meter
generally, the unit of Cr is MV, and the unit of ACR is MVH
according to the previous description, the CR value is the voltage value at both ends of the sampling resistor, and the typical 12bit Cr is shown in Table 2
Where s is the sign bit and 20 is the LSB. If the full bias value of Cr is f, the calculation formula of LSB is as follows:
if the reading of Cr is m and the sampling resistance is RSNs, the actual current value is:
the current direction is determined by s bit. If the full deviation f is ± 64mv, then LSB is ± fifteen point six two five μ V; The RSNs is 10m Ω The maximum current is ± 6.4A If M is 768, the actual current is
ACR is the cumulative value of voltage at both ends of the sampling resistor, and the typical 16 bit ACR is shown in Table 3
Where s is the sign bit and 20 is the LSB. If the full bias value of ACR is f, the calculation formula of LSB is as follows:
the net charge is determined by S-bit. If the full deviation f is ± 84mvh, then LSB is ± six point two five μ Vh; The RSNs is 10m Ω The maximum power is ± 20.48Ah If M is 7680, then the actual power is:
analysis on the application status of market electricity meter chip
because domestic handheld and portable devices can be divided into two parts, one is smart phone, the other is two-way tablet computer / mid. For the application of these two markets, the main reference designs of these two blocks are provided by AP manufacturers. For example, qcomm, Broadcom, MTK, NVIDIA, Samsung, Hisilicon, etc. of smart phones, as well as Quan, Juli, Ruixin, Zhongxing, etc. of tablet / mid
most of the domestic manufacturers of handheld and portable devices have to rely on the AP factory to provide technical support when developing new procts, so most of the reference designs of the original factory do not change the use of components except wiring. So as long as the reference design of the original factory uses the coulometer of a certain manufacturer, or such as qcomm, Broadcom, MTK, etc. uses their own coulometer in PMIC, and then realizes the function of the coulometer through ap calculation. At present, in the market, because the original design of Apple's mobile phone and tablet uses ti's solution, so in the market, Ti can be said to be the manufacturer that has been working in the electricity meter for the longest time and has the largest market share. Secondly, because Samsung adopts Maxim's electricity meter scheme, Maxim can be said to be the second elder brother in the electricity meter market
for the rest, whether the coulometer is placed in the PMIC, or the electric energy meter with self-learning function, such as cellwise, are all the plans that have entered the market in recent two years. The most important reason for this trend is that consumers begin to demand the accuracy of power indication of devices. This requirement is reflected in the operating systems of all handheld and portable devices (IOS, Android, Windows Phone), as well as all kinds of apps. From this trend, we can clearly see that the role of electricity meter in handheld and portable devices is becoming more and more important
the max17040 chip is taken as the representative to make a detailed description
1. The working principle of max17040
the electricity meter max17040 measures the battery power through the chip. The integrated circuit of the chip itself is relatively complex. At the same time, it can realize some processing through some algorithms on the software, which makes the measured power more accurate. Another advantage is that the digital output is directly read by IIC, which makes us more unified in circuit design and program processing
as shown in the figure below, the relationship between max17040 and the main controller of the battery box, an ad pin is connected to the battery Vbat +, and the detected power information is transmitted to the main controller through IIC
the following is the circuit diagram, the circuit interface is relatively simple, Vbat + is connected to the cell of max17040, IIC is connected to the iic2 interface of the main control, which we need to configure in the program. Look, this device is relatively simple
take a look at the internal structure of max17040. In fact, it is also an ad conversion process, which can be realized by a single chip. It looks more professional. The cell interface is actually a pin for ADC conversion. We can see that the chip has its own clock (TI)