智能充电器设计参考资料APPlication note
8-bit
Microcontrollers
Application Note
Rev. 8080A-AVR-09/07
AVR458: Charging Lithium-Ion Batteries with
ATAVRBC100
Features
? Fully Functional Design for Charging Lithium-Ion Batteries ? High Accuracy Measurement with 10-bit A/D Converter ? Modular “C” Source Code
? Easily Adjustable Battery and Charge Parameters
? Serial Interface for Communication with External Master
? One-wire Interface for Communication with Battery EEPROM ? Analogue Inputs for Reading Battery ID and Temperature
? Internal Temperature Sensor for Enhanced Thermal Management ?
On-chip EEPROM for Storage of Battery and Run-Time Parameters
1 Introduction
This application note is based on the ATAVRBC100 Battery Charger reference design (BC100) and focuses on how to use the reference design to charge Lithium-Ion (Li-Ion) batteries. The firmware is written entirely in C language (using IAR ? Systems Embedded Workbench) and is easy to port to other AVR ? microcontrollers.
This application is based on the ATtiny861 microcontroller but it is possible to migrate the design to other AVR microcontrollers, such as pin-compatible devices ATtiny261 and ATtiny461. Low pin count devices such as ATtiny25/45/85 can also be used, but with reduced functionality.
2
AVR458
8080A-AVR-09/07
2 Theory of Operation
Battery charging is made possible by a reversible chemical reaction that restores energy in a chemical system. Depending on the chemicals used, the battery will have certain characteristics. A detailed knowledge of these characteristics is required in order to avoid inflicting damage to the battery.
2.1 Li-Ion Battery Technology
Lithium-Ion batteries have the highest energy/weight and energy/space ratios of modern rechargeable batteries /1/ (See “References” section on page 29). It is currently the fastest growing battery system on the market, with end applications such as notebook computers, cell phones, portable media players, Personal Digital Assistants (PDA), power tools and medical devices.
Compared to traditional, rechargeable batteries, Li-Ion batteries have low internal resistance, high cycle life, fast charge time, low self-discharge, low toxicity and no maintenance requirements. For example, lithium-ion cells with cobalt cathodes hold twice the energy of a nickel-based battery and four-times that of lead acid /2/. Lithium-ion is a low maintenance system, an advantage that most other chemistries cannot claim. There is no memory effect with lithium-ion and the battery does not require scheduled cycling to prolong its life. Lithium-ion has a low self-discharge and is environmentally friendly. Disposal causes minimal harm.
Drawbacks of Li-Ion batteries include low tolerance of overcharge and the need for embedded protection circuitry. An electrical short can result in a large current flow, a temperature rise and thermal runaway in which flaming gases are vented.
2.1.1 Safety
Lithium-ion batteries are safe, provided certain precautions are met when charging and discharging. In addition, battery manufacturers ensure a high level of reliability by adding three layers of protection, as follows:
1. The amount of active material is limited to achieve a workable equilibrium of energy density and safety.
2. Various safety mechanisms are included within each cell.
3. An electronic protection circuit is added inside the battery pack.
Cell protection devices work as follows:
? A PTC (positive temperature coefficient) device acts as a protection to inhibit high current surges.
? The CID (circuit interrupt device) opens the electrical path if an excessively high charge voltage raises the internal cell pressure.
? The safety vent allows a controlled release of gas in the event of a rapid increase in cell pressure.
AVR458
3
8080A-AVR-09/07
The electronic protection circuit works as follows:
? A solid-state switch is opened if the charge voltage of any cell reaches a given threshold.
? A fuse cuts the current flow if the skin temperature of the cell approaches 90°C (194°F).
? The current path is cut when cell voltage drops below a given threshold. This is in order to prevent the battery from over-discharging.
Today, lithium-ion is one of the most successful and safe battery chemistries available with billions of cells being produced every year.
2.2 Charging Li-Ion Batteries
There is only one way to charge lithium-based batteries /3/. Manufacturers of Lithium-Ion cells have very strict guidelines in charge procedures and the packs should be charged as per the manufacturers "typical" charge technique.
Li-Ion batteries are charged using constant voltage, with current limiter to avoid overheating in the initial stage of the charging process. Charging is terminated when the charge current drops below a threshold set by the manufacturer. The battery takes damage from overcharging and may explode if overcharged.
2.2.1 Safety
Static electricity or a faulty charger may destroy the battery's protection circuit and turn solid-state switches to a permanent ON position. This may happen without the user knowing. A battery with a faulty protection circuit may function normally but does not provide protection against abuse.
Consumer grade lithium-ion batteries cannot be charged below 0°C (32°F). If charged at cold temperatures, battery packs may appear to be charging normally but chemical reactions inside the cells may cause permanent damage and can compromise the safety of the pack.
The battery will become more vulnerable to failure if subjected to impact, crush or high rate charging.
The battery must remain cool. A battery pack that gets hot during charge should not be used.
2.2.2 Priming & Charge Intervals
Unlike many other types of rechargeable batteries, Lithium-Ion batteries do not need priming. The first charge of a Li-Ion battery is no different than the 10th or the 100th charge.
Lithium-ion batteries may be – and should be – charged often. The battery lasts longer with partial rather than full discharges. Full discharges should be avoided because of wear.
The battery loses capacity due to aging, whether used or not.
4
AVR458
2.2.3 Charge Stages
There are two charge stages of a Lithium-Ion battery, as follows:
1. Constant current. Charging of a Li-Ion battery starts with applying constant current to the battery. The size of the charge current is battery-dependent and given by the manufacturer. This stage is complete when battery voltage has reached the threshold given by the manufacturer.
2. Constant voltage. After battery threshold voltage has been reached the charger will switch from supplying constant current to supplying constant voltage. This stage is complete when charge current has dropped below the threshold given by the manufacturer.
The below figure illustrates voltage and current of a lithium-ion battery during charging.
Figure 1-1. Charge stages and limits of a Varta PoLiFlex ? cell
In the figure above, “Overcharge” is the level at which cell protection circuitry cuts in and opens a solid-state switch and discontinues the charge current path. After this, battery voltage typically needs to drop several hundred millivolts before the current path is restored. “Overdischarge” is the level at which the current path is cut in order to prevent the battery from over-discharging. Recommended battery operating voltage is typically a margin away from overcharge and discharge limits.
8080A-AVR-09/07
AVR458
5
8080A-AVR-09/07
2.2.4 Typical Charge Characteristics
Battery specifications should always be verified from manufacturer’s data sheets. Below is a summary of typical lithium-ion battery charge characteristics. Actual parameters may vary.
Table 1-1. Typical Charge Characteristics
Parameter Typical Value
Charge time 3 hours Charge current 1 C Charge efficiency 99.9 % Charge current threshold 0.03 C Charge voltage
4.20 V Charge voltage tolerance (per cell) ± 0.05 V Temperature range 0 … +45 °C Humidity range
65 ± 20 RH
2.2.5 Typical Battery Characteristics
The table below summarises manufacturer’s data for the batteries types used in this application. Other types of batteries may be used, but may require adjustments to software and/or hardware.
Table 1-2. Manufacturer’s data for Varta PoLiFlex range of lithium-ion batteries /4/
Parameter
PLF
443441 PLF 383562 PLF 503562 2P/PLF 503562 Unit Rated capacity (typical) 550
750
1000
2000
mAh Nominal voltage 3.70 V Operating voltage range 2.75 … 4.20
V Charge voltage
4.20 V Charge voltage tolerance ± 50
mV
Charge current 520 720 955 955 mA Charge cut-off time 3 3 3 4 hours Charge cut-off current 10 14 19 38 mA RID (resistor ID)
3.9
6.8
10
24
k ?
NTC 10 k ? B-value 3435 K
Overcharge detection 4.35 V Overdischarge detection
2.20
V
6
AVR458
8080A-AVR-09/07
2.3 Battery Charger
This application note is based on the ATAVRBC100 Battery Charger reference design by Atmel ?. The reference design is rather complex and has loads of features but this application focuses on the low end of the design, only. For more information on the BC100, please see AVR451 - BC100 Hardware User's Guide /5/.
2.3.1 Microcontroller
The BC100 hosts two microcontrollers; a master (ATmega644, by default) and a slave (an ATtiny25/45/85 or ATtiny261/461/861, by default). The master microcontroller is outside the scope of this application but it may be noted that the microcontrollers are capable of communicating with each other such that the master may request data from the slave at any time.
The slave microcontroller is fully capable of handling all tasks related to battery charging and it does not require a master microcontroller to be present. It constantly scans the connectors for batteries and, if found, charges them when required. The slave microcontroller also constantly monitors the hardware for any anomalies.
2.3.2 Power supply
This application note does not focus on the power supply. It may, however, be noted that the firmware constantly monitors the input voltage levels in order to make sure operation is reliable.
2.3.3 Buck switches
The firmware on the slave microcontroller controls any of the three buck switches on board the BC100. The default is to use a high-frequency PWM output of the microcontroller to adjust the voltage and current flow to the battery. The voltage (and current) of the buck switches are directly proportional to the duty cycle of the PWM signal.
AVR458
7
8080A-AVR-09/07
3 Battery Charger Hardware
This application note is based on the ATAVRBC100 Battery Charger reference design. A detailed hardware description will not be provided in this document. Please see AVR451 - BC100 Hardware User's Guide for detailed information.
3.1 Configuration
The ATAVRBC100 Battery Charger reference design must be configured as detailed below.
3.1.1 Microcontroller
The hardware should be populated as follows: ? Make sure socket SC300 is empty
? Populate socket SC301 with an ATtiny861
It is possible to use other AVR microcontrollers but this application has been optimised for using ATtiny861. Pin compatible replacements such as ATtiny261 and ATtiny461 /6/ may be used if the compiled code size is decreased. This can be done by increasing the optimisation of the compiler and by removing unwanted features from the firmware.
Other microcontroller options include ATtiny25, ATtiny45 and ATtiny85 /7/. These (as well as other 8-pin AVR microcontrollers) use the SC300 socket on BC100. It should be noted that due to reduced pin count the 8-pin microcontrollers provide less features than the default 20-pin.
3.1.2 Programming Connector
The microcontroller can be programmed via 6-pin connector J301, using either SPI or debugWIRE.
Please note that in some hardware revisions of BC100 it may be necessary to remove R303 and disconnect pin 15 of U202. This procedure frees the /RESET line for use by external programmer or debugger but removes the possibility for the master microcontroller to reset the slave. Do not engineer the board unless required. Alternatively, the microcontroller can always be programmed off-board.
3.1.3 Jumpers
The jumpers should be configured as follows:
? J400, J401, J407 & J408: Set jumpers to use Buck Switch C (20V / 1A) ? J405 & J406: Set jumpers to 1/4 (max measurable voltage 10V)
Other configurations are possible, but may require firmware changes. See variable VBAT_RANGE in file ADC.h.
8
AVR458
3.1.4 Battery
This application uses a particular type of lithium-ion batteries and all configurations presented here are based on manufacturer’s data. Other lithium-ion batteries may naturally be used but it is up to the user to look up battery data from manufacturer’s data sheets and make sure necessary adjustments are done to firmware and hardware. See section 4.5.1 and file battery.h.
The figure below illustrates connection pads of the lithium-ion batteries used in this application.
Figure 1-2. Connection pads of a Varta PoLiFlex cell.
The battery is connected to the battery charger as follows. Table 1-3. Connecting battery to charger
Battery Connector Charger Connector Note - (minus) BATTERY-
NTC NTC/RID Battery temperature measurement
ID SCL RID, Battery identification resistor + (plus)
BATTERY+
3.1.5 Data EPROM
Some batteries are equipped with an embedded EPROM for storing charge and manufacturing data. This application supports the use of EPROM via a one-wire interface. The default is a DS2502 EPROM connected as follows. Table 1-4. Connecting external EPROM DS2502 to charger
EPROM Pin
Charger Connector
DATA 1-WIRE/SDA GND BATTERY-
If an EPROM is not connected to the battery charger the application will simply disregard its absence.
8080A-AVR-09/07
AVR458
9
8080A-AVR-09/07
3.1.6 Supply Voltage
The higher the supply voltage, the higher the minimum current the buck switches can provide. For example, if supply voltage is about 9 V and buck charger C is used to charge a battery at 4.20 V then the minimum attainable current is about 80 mA. At this point the smallest decrease in PWM duty cycle (i.e. reducing the contents of OCR1B by 1) will effectively turn off the current to the battery.
It is recommended to use a supply voltage some three volts above battery charge voltage. In this application the battery is being charged at 4.20 V and the recommended supply voltage is therefore 7.5 V.
Another method to lower the minimum charge current the hardware can provide is to use a buck switch with a large inductor. In BC100 this means Buck Switch A.
10
AVR458
8080A-AVR-09/07
4 Battery Charger Software
The firmware is written in C language using IAR Systems Embedded Workbench, version 4.20. Since the firmware has been written entirely in C, it should not be a difficult task to port it to other AVR C-compilers. Some compiler specific details may, however, need to be rewritten.
In the table below are listed the files that are relevant to the compiler project. Table 1-5. Project files (see IAR EW workspace file BC100_tiny.eww)
File Type Note
ADC.c
C source code
ADC.h Header file Functions related to A/D converter AVR458.c AVR458.h Functions related to the different states
and charging
battery.c
C source code
battery.h Header file Battery-specific definitions and functions related to battery control & data acquisition
main.c C source code main.h Header file Main program / Program entry point menu.c C source code menu.h Header file State machine definitions
OWI.c C source code OWI.h Header file Functions related to one-wire interface PWM.c C source code PWM.h Header file
Functions related to generating pulse-width modulated output
time.c C source code
time.h Header file Functions related to timekeeping and measurement of time
USI.c
C source code
USI.h Header file
Functions related to serial interface
4.1 Overview
The firmware integrates all functions required to charge two lithium-ion batteries. Batteries are connected to separate ports such that one may be charged while the other is idle. The firmware is fully automated and capable of stand-alone battery monitoring and charging but it may also be used together with a master microcontroller, such as the one implemented in BC100.
By default, the firmware fits into an ATtiny861 (build option: debug) or an ATtiny461 (build option: release). Memory requirements of the firmware are summarised in the table below.
AVR458
Table 1-6. Memory requirements of firmware
Build option Memory Approximate value
CODE (Flash) 5800 bytes DATA (SRAM) 270 bytes Debug
XDATA (EEPROM) 130 bytes CODE (Flash)
3900 bytes DATA (SRAM) 270 bytes Release
XDATA (EEPROM)
130 bytes
4.2 State Machine
The state machine is rather simple and resides in the main() function. It simply looks up the address of the next function to execute and then jumps to that function. The flow chart of the state machine is illustrated in the figure below. Figure 1-3. Flow chart of main function, including the state machine
Upon return, the state machine expects the function to indicate the next state as a return argument. The recognised return codes are described in the table below.
Table 1-7. State machine codes (see source code, menu.h)
Label (1)Related Function (2)Description
INIT Initialize() Entry state
BATCON BatteryControl() Check hardware and batteries PREQUAL Charge() Raise battery voltage, safety check SLEEP Sleep() Low power consumption mode CCURRENT Charge() Charge with constant current CVOLTAGE Charge() Charge with constant voltage ENDCHARGE Charge() End of successful charge DISCHARGE Discharge()
ERROR Error()
Resolve error, if possible
Notes:
1. Name of label, excluding leading “ST_”
2. Function name, as declared in source code
11
8080A-AVR-09/07
12 AVR458 State functions are described in the following sections.
4.2.1 Initialize()
The initialisation function is the first state function that will be executed after device
reset. The flow chart of the function is shown in the figure below.
Figure 1-4. Flow chart of initialisation function
The initialisation function always exits with the same return code, pointing to the state
function for battery control.
4.2.2 BatteryControl()
The battery control function verifies that jumpers are set correctly and then checks to
see if there are any enabled batteries present that require charging. The program flow
is illustrated in the figure below.
8080A-AVR-09/07
AVR458
Figure 1-5. Flow chart of battery control function
4.2.3 Charge()
The charge function contains the charging algorithm divided into stages. For this application, it has four stages:
?
Prequalification - during which the battery is charged with a constant current until a sufficient charge voltage is reached. If this happens within a given time limit, the battery is considered good and the charger may continue on the next stage. If time runs out before the voltage is reached, or battery temperature goes out of limits, the battery is considered bad and charging is halted.
?
Constant current charge - during which the battery is charged with a higher, battery-specific current until the battery voltage reaches its maximum. If this happens within the battery’s maximum charge time limit, the charger goes to the next stage. If the time limit expires, or battery temperature goes out of limits, the battery is considered bad and charging is halted.
?
Constant voltage charge – during which the battery is charged at the maximum battery voltage until the charge current sinks beneath a battery-specific cut-off limit, or the maximum charge time limit expires. Here too, charging is halted if battery temperature goes out of limits.
?
End charge – in which the charger decides whether to go into the sleep state, or to attempt a charge of the other battery.
ChargeParameters and HaltParameters are central variables in this function. The program flow of this state function is illustrated in the figure below.
13
8080A-AVR-09/07
14 AVR458 Figure 1-6. Flow chart of the charge state function
4.2.4 Discharge()
This function has not been implemented.
8080A-AVR-09/07
AVR458
4.2.5 Sleep()
The application enters sleep mode when all batteries have been fully charged. It wakes up at regular intervals to check the current status of the batteries. Sleep mode is terminated as soon as any battery requires charging. Sleep mode is illustrated in the flow chart below. Figure 1-7. Flow chart of sleep function
4.2.6 Error()
Program flow is diverted here when an error has occurred. The error handler contains some simple algorithms that try to resolve the most common problems. Program execution will exit the error handler when all sources of error have been cleared. The program flow is illustrated in the figure below.
15
8080A-AVR-09/07
16
AVR458
Figure 1-8. Flow chart of error handler
8080A-AVR-09/07
AVR458
17
8080A-AVR-09/07
4.3 Charging Functions
These functions are called by Charge() after all parameters have been set.
4.3.1 Constant Current/Voltage
These two functions are similar, apart from what ADC measurements they try to keep within limits. Therefore, only the flow chart for ConstantCurrent() is illustrated in the figure below. They both make use of the variable ChargeParameters.
If a Master microcontroller is present, it may temporarily stop the charging by flagging a charge inhibit. This is to prevent battery damage during prolonged serial transfers.
18
AVR458
Figure 1-9. Flow chart for ConstantCurrent()
4.3.2 Charge Halt Determination
Charge halt is determined by HaltNow(). This function is called by ConstantCurrent() and ConstantVoltage() every time they loop, to decide if a stage of charging is done. With the variable HaltParameters the user can specify at what terms the charging should be halted, and if an error should be flagged if f.ex. the time limit expires. An error flag will also result in ST_ERROR being set as the next state, thereby aborting
8080A-AVR-09/07
AVR458
19
8080A-AVR-09/07
the charge. If no errors are flagged, the next desired state, set earlier in Charge(), will apply.
Lastly, the function checks if temperature is within limits, if the battery is OK and if mains voltage is above minimum. Should any of these tests fail, the next state is set to an appropriate error handler (ST_ERROR, ST_INIT or ST_SLEEP) and charging is aborted.
20
AVR458
Figure 1-10. Flow chart for HaltNow() part 1.
8080A-AVR-09/07
基于单片机的智能充电器设计毕业论文
基于单片机的智能充电器设计毕业 论文 目录 1 绪论 (1) 1.1课题研究的背景、目的及意义 (1) 1.2国外研究现状 (2) 1.2.1国外研究现状 (2) 1.2.2国研究现状 (2) 1.3研究容与章节安排 (5) 2 方案比较和选择 (6) 2.1总体设计框图 (6) 2.2电源模块 (7) 2.2.1电源方案的选择 (7) 2.3充电方法 (8) 2.3.1锂电池的充电特性 (8) 2.3.2充电方案的选择 (9) 2.4 SOC估算方法 (10) 2.4.1 SOC估算方法的选择 (10) 2.5通信方式 (11)
2.5.1 通信方式的选择 (11) 2.6本章小结 (12) 3 硬件设计与实现 (13) 3.1单片机电路 (13) 3.2充电电源电路 (16) 3.2.1变压电路 (16) 3.2.2整流、滤波电路 (17) 3.2.3 TL494脉宽调制电路 (17) 3.2.4 DC-DC电路 (19) 3.3电压采集电路 (19)
3.4温度采集电路 (21) 3.5报警电路 (21) 3.6本章小结 (22) 4 软件设计与实现 (23) 4.1软件开发环境 (23) 4.1.1 Qt5.4集成开发环境 (23) 4.2单片机程序设计 (23) 4.2.1 整体设计逻辑概述 (23) 4.2.2 电压、温度数据采集 (24) 4.3上位机软件程序设计 (25) 4.3.1 整体设计概述 (25) 4.3.2 程序逻辑流程图 (25) 4.3.3 UI界面 (25) 4.4 上下位机的通信设计 (27) 4.4.1 通信协议概述 (27) 4.4.2 上下位机通信流程图 (27) 4.5 本章小结 (28) 5 调试与分析 (29) 5.1充电电路检测 (29) 5.2温度电路检测 (30) 5.3电压电路检测 (31) 5.4充电器运行检测 (32)
毕业设计_基于MAX1898的智能充电器设计
基于MAX1898的智能充电器设计 在人们日常工作和生活中，充电器的使用越来越广泛。从随身听到数码相机，从手机到笔记本电脑，几乎所有用到电池的电器设备都需要用到充电器。充电器为人们的外出旅行和出差办公提供了极大的方便。 单片机在电池充电器领域也有着广泛的应用，利用它的处理控制能力可以实现充电器的智能化。充电器各类繁多，但从严格意义上讲，只有单片机参与处理和控制的充电器才能称为智能充电器。 1 实例说明 随着手机在世界范围内的普及使用，手机电池充电器的使用也越来越广泛。 本章将通过一个典型实例介绍51单片机在实现手机电池充电器方面的应用。实例所实现的充电器是一种智能充电器，它在单片机的控制下，具有预充、充电保护、自动断电和充电完成报警提示功能。 实例的功能模块如下。 ●单片机模块：实现充电器的智能化控制，比如自动断电、充电完成报警提示等。 ●充电过程控制模块：采用专用的电池充电芯片实现对充电过程的控制。 ●充电电压提供模块：采用电压转换芯片将外部+12V 电压转换为需要的+5V电压， 该电压在送给充电控制模块之前还需经过一个光耦模块。 ●C51程序：单片机控制电池充电芯片实现充电过程的自动化，并根据充电的状态给 出有关的输出指示。
2 设计思路分析 要实现智能化充电器，需要从下面两个方面着手。 （1）充电的实现。它包括两部分：一是充电过程的控制；二是需要提供基本的充电电压。（2）智能化的实现。在充电器电路中引入单片机的控制。 2.1 为何需要实现充电器的智能化 充电器实现的方式不同会导致充电效果的不同。 由于充电器多采用大电流的快速充电法，在电池充满后如果不及时停止会使电池发烫，过度的充电会严重损害电池的寿命。一些低成本的充电器采用电压比较法，为了防止过充，一般充电到90%就停止大电流快充，而采用小电流涓流补充充电。 手机电池的使用寿命和单次使用时间与充电过程密切相关。锂电池是手机最为常用的一种电池，它具有较高的能量重量比、能量体积比、具有记忆效应，可重复充电多次，使用寿命较长，价格也越来越低。锂电池对于充电器的要求比较苛刻，需要保护电路。为了有效利用电池容量，需将锂电池充电至最大电压，但是过压充电会造成电池损坏，这就要求较高的控制精度。另外，对于电压过低的电池需要进行预充，充电器最好带有热保护和时间保护，为电池提供附加保护。 一部好的充电器不但能在短时间内将电量充足，而且还可以对电池起到一定的维护作用，修复由于使用不当造成的记忆效应，即容量下降（电池活性衰退）现象。设计比较科学的充电器往往采用专用充电控制芯片配合单片机控制的方法。专用的充电芯片具备业界公认较好的－△V 检测，可以检测出电池充电饱和时发出的电压变化信号，比较精确地结束充电工作，通过单片机对这些芯片的控制，可以实现充电过程的智能化，例如，在充电后增加及时关断电源、蜂鸣报警和液晶显示等功能。充电器的智能化可以缩短充电的时间，同时能够维护电池，延长电池使用寿命。 2.2 如何选择电池充电芯片 目前市场上存在大量的电池充电芯片，它们可直接用于进行充电器的设计。在选择具体的电池充电芯片时，需要参考以下标准。 ●电池类型：不同的电池（锂电池、镍氢电池、镍镉电池等）需选择不同的充电芯片。 ●电池数目：可充电池的数目。 ●电流值：充电电流的大小决定了充电时间。 ●充电方式：是快充、慢充还是可控充电过程。 本例要实现的是手机的单节锂离子电池充电器，要求充电快速且具有优良的电池保护能力，据此选择Maxim公司的MAX1898作为电池充电芯片。
镍氢电池充电器电路图及原理分析
镍氢电池充电器电路图及原理分析 镍氢电池充电器原理图:由LM324组成，用TL431设置电压基准，用S8550作为调整管，把输入电压降压，对电池进电行充电，电路附图所示.其工作原理是: 1.基准电压Vref形成 外接电源经插座X、二极管VD1后由电容C1滤波。VD1起保护作用，防止外接电源极性反接时损坏TL431。R3、R4、R5和TL431组成基准电压Vref，根据图中参数Vref= 2.5×(100+820)／820=2.80(v)，这个数据主要是针对镍氢充电电池而设计(单节镍氢充电电池充满后电压约 为1.40V)。 2.大电流充电 (1)工作原理 接入电源，电源指示灯LED(VD2)点亮。装入电池(参考图片，实际上是用导线引出到电池盒，电池装在电池盒中)，当电池电压低于Vref时，IC1-1输出低电平，VT1导通，输出大电流给电池充电。此时，VT1处于放大状态-这是因为电池电压和-VD4压降的和约为3.2V(假设开始充 电时电池电压约为2.5V)，而经VD1后的电压大约5.OV，所以，VT1的发射极－集电极压差远大于0.2V，当充电电流为300mA时，VT1发热比较严重，所以最好用PT=625mW的S8550，或者适当增大基极电阻以减小充电电流(注：由于LM324低电平驱动能力较小，实测IC1-2，IC1-4输出低电平并不是0V，而是约为0.8V)。 (2)充电的指示 首先看IC1-3的工作情况：其同相端1O脚通过R13接Vref,R14接成正反馈，反相端9脚外接电容，并有一负反馈通路，所以，它实际上构成了滞回比较器。刚开始时C2上端没有电压，则IC1-3输出高电平。这个高电平有两个放电通路，一个通路是通过R14反馈到10脚，另一通路是经电阻R15对电容C2充电，当充电的电压高于10脚电压V+ 时，比较器翻转输出低电平；与此同时，由于R14的反馈作用，10脚电压立即下跳到V-，这时，电容C2通过电阻R15放电，当放电的电压小于10脚电压V-时，比较器再次翻转输出高电平，由于R14的反馈作用，10脚电压立即上跳到V+，此后电路一直重复上述过程，因此，IC1-3的输出为频率固定的方波信号。 其次看IC1-4的工作情况：电池电压经R2、R16分压，接IC1-4的12脚，因为R2< 《单片机原理及应用》课程设计报告书 课题名称基于单片机智能充电器的设计 姓名 学号 专业 指导教师 机电与控制工程学院 年月日 任务书 一、设计题目：基于单片机智能充电器的设计 二、设计要求：（1）在单片机的控制系，具有充电保护的功能。 （2）能够自动断电和充电完成报警提示功能。 （3）能够实现充电器的智能化控制。 （4）能够方便快捷地答道正常充电的标准。 目录 一、绪论 (1) 二、程序系统流程图 (8) 三、硬件设计 (9) 四、单片机选择 (17) 五、充电过程 (28) 六、总结 (29) 七、附录 (30) 一、绪论 1.1概述 如今，随着越来越多的手持式电器的出现，对高性能、小尺寸、重量轻的电池充电器的需求也越来越大。电池技术的持续进步也要求更复杂的充电算法以实现快速、安全的充电。因此需要对充电过程进行更精确的监控，以缩短充电时间、达到最大的电池容量，并防止电池损坏。与此同时，对充电电池的性能和工作寿命的要求也不断地提高。 电池充电是通过逆向化学反应将能量存储到化学系统里实现的。由于使用的化学物质的不同，电池有自己的特性。设计充电器时要仔细了解这些特性以防止过度充电而损坏电。 目前，市场上卖得最多的是旅行充电器，但是严格从充电电路上分析，只有很少部分充电器才能真正意义上被称为智能充电器，随着越来越多的手持式电器的出现，对高性能、小尺寸、轻重量的电池充电器的需求也越来越大。 电池技术的持续进步也要求更复杂的充电算法以实现快速、安全地充电，因此，需要对充电过程进行更精确地监控(例如对充、放电电流、充电电压、温度等的监控)，以缩短充电时间，达到最大的电池容量，并防止电池损坏。因此，智能型充电电路通常包括了恒流／恒压控制环路、电池电压监测电路、电池温度检测电路、外部显示电路(LED或LCD显示)等基本单元。其框图如下： 前言 (4) 第一章充电器原理 (5) 1.1 蓄电池与充电技术 (5) 1.2 密封铅酸蓄电池的充电特性 (5) 1.3 充电器充电原理 (6) 1.3.1 蓄电池充电理论基础 (6) 1.3.2 充电器的工作原理 (8) 第二章总体设计方案 (10) 2.1 系统设计 (10) 2.2 方案策略 (10) 第三章硬件电路设计 (12) 3.1 电路总体设计 (12) 3.2 芯片介绍 (12) 3.2.1 LM358双运放 (12) 3.2.2 UC3842单管开关电源 (13) 3.2.3 EL817光耦合器 (14) 3.2.4 场效应管K1358 (15) 3.3 电动车充电器原理及各元件作用的概述 (16) 3.3.1 充电器原理图 (16) 图3.5 充电器原理图 (16) 3.3.2 各元器件作用概述 (16) 3.4 功能模块电路设计 (17) 3.4.1 第一路通电开始 (17) 3.4.2 第二路UC3842电路 (17) 3.4.3 第三路LM358（双运算放大器）电路 (18) 3.5 电动车充电器改进方案 (21) 3.5.1 增加充满电发声提示电路 (21) 3.5.2 加散热风扇 (22) 第四章总结与展望 (23) 致谢 (25) 电动车智能充电器设计及应用 中文摘要： 本设计介绍了充电器对蓄电池充电的一般原理，从阀控蓄电池内部氧循环的设计理念出发，研究各种充电方法对铅酸蓄电池寿命的影响。针对蓄电池充电过程中出现的种种问题，分析现有各种充电方法存在的问题，提出一种可对铅酸蓄电池实现四段式慢脉冲充电的智能充电器设计方案。控制开关电源的脉冲频率和占空比，从而调节充电电流和电压，实现对蓄电池的分级慢脉冲充电。这个方案不仅可实现快速充电，同时可以减少析气，消除硫化，进行均衡充电，从而大大地延长了铅酸蓄电池的使用寿命。 关键词：慢脉冲充电；蓄电池；充电器； Abstract: The design describes the charger to the battery charger of the general principles, from the internal oxygen cycle of valve-regulated battery design concepts starting to study a variety of charging methods for lead-acid battery life implications. For battery charging problems arising in the process, analysis of existing problems in a variety of charging methods, proposed a lead-acid batteries could achieve the Four-slow pulse charge of the intelligent charger design. Control the switching power supply pulse frequency and duty cycle, thus regulating charge current and voltage to achieve the classification of the battery charge with slow pulse. This program not only for fast charging, while reducing analysis of gas, to eliminate sulfide, a balanced charge, thus greatly extending the service life of lead-acid batteries. Key words: slow pulse charge; batteries; charger; 毕业论文声明 本人郑重声明： 1．此毕业论文是本人在指导教师指导下独立进行研究取得的成果。除了特别加以标注地方外，本文不包含他人或其它机构已经发表或撰写过的研究成果。对本文研究做出重要贡献的个人与集体均已在文中作了明确标明。本人完全意识到本声明的法律结果由本人承担。 2．本人完全了解学校、学院有关保留、使用学位论文的规定，同意学校与学院保留并向国家有关部门或机构送交此论文的复印件和电子版，允许此文被查阅和借阅。本人授权大学学院可以将此文的全部或部分内容编入有关数据库进行检索，可以采用影印、缩印或扫描等复制手段保存和汇编本文。 3．若在大学学院毕业论文审查小组复审中，发现本文有抄袭，一切后果均由本人承担，与毕业论文指导老师无关。 4.本人所呈交的毕业论文，是在指导老师的指导下独立进行研究所取得的成果。论文中凡引用他人已经发布或未发表的成果、数据、观点等，均已明确注明出处。论文中已经注明引用的内容外，不包含任何其他个人或集体已经发表或撰写过的研究成果。对本文的研究成果做出重要贡献的个人和集体，均已在论文中已明确的方式标明。 学位论文作者（签名）： 年月 关于毕业论文使用授权的声明 本人在指导老师的指导下所完成的论文及相关的资料（包括图纸、实验记录、原始数据、实物照片、图片、录音带、设计手稿等），知识产权归属华北电力大学。本人完全了解大学有关保存，使用毕业论文的规定。同意学校保存或向国家有关部门或机构送交论文的纸质版或电子版，允许论文被查阅或借阅。本人授权大学可以将本毕业论文的全部或部分内容编入有关数据库进行检索，可以采用任何复制手段保存或编汇本毕业论文。如果发表相关成果，一定征得指导教师同意，且第一署名单位为大学。本人毕业后使用毕业论文或与该论文直接相关的学术论文或成果时，第一署名单位仍然为大学。本人完全了解大学关于收集、保存、使用学位论文的规定，同意如下各项内容：按照学校要求提交学位论文的印刷本和电子版本；学校有权保存学位论文的印刷本和电子版，并采用影印、缩印、扫描、数字化或其它手段保存或汇编本学位论文；学校有权提供目录检索以及提供本学位论文全文或者部分的阅览服务；学校有权按有关规定向国家有关部门或者机构送交论文的复印件和电子版，允许论文被查阅和借阅。本人授权大学可以将本学位论文的全部或部分内容编入学校有关数据库和收录到《中国学位论文全文数据库》进行信息服务。在不以赢利为目的的前提下，学校可以适当复制论文的部分或全部内容用于学术活动。 论文作者签名：日期： 指导教师签名：日期： 手机充电器电路设计 摘要：通过对课程的学习设计。了解手机充电器的工作原理及设计流程，确定相关参数和电路图。 关键字：隔离变压器频率绝缘电阻绝缘强度可燃性自由跌落湿热试验工作原理工作流程 1 前言（李洋） 1 电路设计思想 从手机锂离子二次电池的恒流／恒压充电控制出发，用220V 交流电通过配置的内置储能锂电池对手机锂离子电池充电。电路的具体工作流程如图1所示。 图1 工作流程图 2 电路设计方案 充电芯片选用美信半导体公司的锂电池充电芯片，这款充电芯片具 有很强的充电控制特性，可外接限流型充电电源和P沟道场效应管，能对单节锂电池进行安全有效的快充。其最大特点是在不使用电感的情况下仍能做到很低的功率耗散，且充电控制精度达0.75％；可以实现预充电；具有过压保护和温度保护功能，其浮充方式能够充至最大电池容量。当充电电源和电池在正常的工作温度范围内时，接通电源将启动一次充电过程。充电结束的条件是平均的脉冲充电电流达到快充电流的1％，或时间超出片上预置的充电时间。所选用的充电芯片能够自动检测充电电源，在没有电源时自动关断以减少电池的漏电。启动快充后打开外接的P型场效应管，当检测到电池电压达到设定的门限时进入脉冲充电方式，充电结束时，外接LED指示灯将会进行闪烁提示。 电路工作原理 内置储能电池的充电及其保护电路其中包括：LED显示、热敏电阻，电流反向保护。ADJ引脚通过10kΩ的电阻与内部1.4V的精密基准源相连接，当ADJ对地没有连接电阻时，电池充电电压阈值为缺省值：VBR ＝4.2V；当需要自行设置充电阈值时，可在ADJ引脚与GND间接一精度为1％的电阻RADJ，阻值由式(1)确定：RADJ＝10kΩ/(VBR/VBRC-1) (1) 由图3可知，充电阈值为4.1V，可得RADJ＝410k 做手机充电器电路设计，需先对其工作环境进行分析，了解其工作原理。 实 习 报 告 实习名称：测控综合大实习 实习内容：智能充电宝设计 姓名： 学号： 专业：测控技术与仪器 学期： 2013-2014 第一学期 任课教师： 实习地点：校内 实习时间： 2013.12 -2014.1 智能充电宝 摘要：现如今，大屏智能手机,平板电脑，笔记本电脑，数码相机等，功能日益多样化，使用也更加频，特别是外出旅游时又是这些终端设备的使用高峰期， 使用频繁带来的电量不够用，于是移动电源充电宝应运而生。虽然手机因品牌,型号等各有不同，但目前市场上的主要多功能性充电宝，都配置有标准的USB 输出，基本能满足目前市场常见的移动设备手机，MP3，MP4，蓝牙耳机，数码相机等数码产品。 本论文将以MSP430和充电芯片MAX1898为基础设计一款手机理电池智能充电宝。首先MAX1898对锂电池进行充电，再接入升压电路、电池保护电路，通过开关切换使终端输出不同电压，充电完成报警引脚以及充电断开控制引脚均用单片机来进行控制，并显示充电状态和充电进度。 关键字：充电宝终端报警控制 Abstract: Now, the big screen intelligent mobile phone, tablet computer, notebook computer, digital camera, functional diversification and the use is more frequency.The terminal equipment using peak when the tourist season. With the frequent use of power brought is not enough, the charging mobile being produced.Although mobile phone is different because of the brand, model , but currently mainly multifunctional charging Po, are equipped with a standard USB output on the market, can basically meet the current market common mobile equipment such as mobile phone, MP3, MP4, Bluetooth headsets, digital cameras and other digital products. This paper will design a Intelligent charging Po based on Single chip microcomputer MSP430 and charging chip MAX1898 .First MAX1898 charging the lithium battery , then access to boost circuit and battery protection circuit.Through the switch terminal output different voltage. Charging complete alarm pin and charging disconnect control pins are regulated by single-chip microcomputer ,and display the state of charge and charging schedule. Key word:charge pal terminal alarming control 目录 第一章绪论 8-bit Microcontrollers Application Note Rev. 8080A-AVR-09/07 AVR458: Charging Lithium-Ion Batteries with ATAVRBC100 Features ? Fully Functional Design for Charging Lithium-Ion Batteries ? High Accuracy Measurement with 10-bit A/D Converter ? Modular “C” Source Code ? Easily Adjustable Battery and Charge Parameters ? Serial Interface for Communication with External Master ? One-wire Interface for Communication with Battery EEPROM ? Analogue Inputs for Reading Battery ID and Temperature ? Internal Temperature Sensor for Enhanced Thermal Management ? On-chip EEPROM for Storage of Battery and Run-Time Parameters 1 Introduction This application note is based on the ATAVRBC100 Battery Charger reference design (BC100) and focuses on how to use the reference design to charge Lithium-Ion (Li-Ion) batteries. The firmware is written entirely in C language (using IAR ? Systems Embedded Workbench) and is easy to port to other AVR ? microcontrollers. This application is based on the ATtiny861 microcontroller but it is possible to migrate the design to other AVR microcontrollers, such as pin-compatible devices ATtiny261 and ATtiny461. Low pin count devices such as ATtiny25/45/85 can also be used, but with reduced functionality. 目录 1课题名称 (1) 2设计主体要求及内容 (1) 3 课题分析与方案论证 (1) 方案一........................................................................................... 错误!未定义书签。 方案二 (3) 4 各局部电路设计 (4) 整流滤波电路 (4) 恒压电路 (5) 恒流电路 (5) 充电提示电路 (7) 5组装调试 (10) 6元器件的选择 (10) 7 设计总结及改进意见 (10) 本方案特点及存在的问题 (11) 改进意见及其他设想 (11) 8 设计心得 (12) 参考文献 1 课题名称 手机充电器的制作。 2 设计主体要求及内容 通信技术的高速发展促使手机种类众多，也导致手机充电器也是多种多样，本设计设计并制作一套手机通用锂电池的充电器。 充电器的简单工作过程如下：交流输入电压经电容降压，二极管整流桥整流后变成直流电，经隔离二极管和滤波电容对手机充电，随着充电时间的增长，电池两端的电压也升高，通过分压器将此电压引入基准电压比较器，其中三个比较器带三个指示灯，分别指示充电的状态，当三个灯全亮时，表示充电已满。通过以上的工作过程描述结合生活经验设计手机实用充电器电路。 技术要求：能够顺利为锂电池充电，有必要的显示、保护功能，充电电压，充电限制电压。 工作要求：独立设计充电器方案，根据本人的方案，购买所需要的元器件和电路板，独立设计并调试正常，要求总投资不得高于20元。 3 课题分析与方案论证 从课题上可以看出设计的主体要求是将市电变换为符合要求的直流电源，整体上应该有降压、整流、滤波、恒压电路。 降压电路可以用最简单的变压器完成，将220V电压变为10V左右的低压，为了让优化波形使其更加稳定可采用滤波电容去除高频干扰。 手机通用的锂电池充电电压为，因此需要设计一个恒压源电路。充电电流在一定程度上影响了充电的时间，过高的电流会缩短电池的使用寿命，所以我们还需要一个可靠地恒流源来保证充电的时间和手机的使用寿命。 当上述条件都具备时对于不同容量的手机电池充电时间是不一样的，因此需要一个不以时间为参考的充电完成信号，我们可以根据电池两端的电压是否达到标准电压来判断是 锂离子电池智能充电器硬件方案 锂离子电池智能充电器硬件的设计 锂离子电池具有较高的能量重量和能量体积比，无记忆效应，可重复充电次数多，使用寿命长，价格也越来越低。一个良好的充电器可使电池具有较长的寿命。利用C8051F310单片机设计的智能充电器，具有较高的测量精度，可很好的控制充电电流的大小，适时的调整，并可根据充电的状态判断充电的时间，及时终止充电，以避免电池的过充。 本文讨论使用C8051F310器件设计锂离子电池充电器的。利用PWM脉宽调制产生可用软件控制的充电电源，以适应不同阶段的充电电流的要求。温度传感器对电池温度进行监测，并经过AD转换和相关计算检测电池充电电压和电流，以判断电池到达哪个阶段。使电池具有更长的使用寿命，更有效的充电方法。 设计过程 1 充电原理 电池的特性唯一地决定其安全性能和充电的效率。电池的最佳充电方法是由电池的化学成分决定的<锂离子、镍氢、镍镉还是SLA电池等）。尽管如此，大多数充电方案都包含下面的三个阶 段： ● 低电流调节阶段 ● 恒流阶段 ● 恒压阶段/充电终止 所有电池都是经过向自身传输电能的方法进行充电的，一节电池的最大充电电流取决于电池的额定容量 毕业设计课题名称：锂电池充电器的设计 总目录 第一部分任务书 第二部分开题报告 第三部分毕业设计正文 第一部分 任 务 书 毕业设计（论文）原创性声明和使用授权说明 原创性声明 本人郑重承诺：所呈交的毕业设计（论文），是我个人在指导教师的指导下进行的研究工作及取得的成果。尽我所知，除文中特别加以标注和致谢的地方外，不包含其他人或组织已经发表或公布过的研究成果，也不包含我为获得及其它教育机构的学位或学历而使用过的材料。对本研究提供过帮助和做出过贡献的个人或集体，均已在文中作了明确的说明并表示了谢意。 作者签名：日期： 指导教师签名：日期： 使用授权说明 本人完全了解大学关于收集、保存、使用毕业设计（论文）的规定，即：按照学校要求提交毕业设计（论文）的印刷本和电子版本；学校有权保存毕业设计（论文）的印刷本和电子版，并提供目录检索与阅览服务；学校可以采用影印、缩印、数字化或其它复制手段保存论文；在不以赢利为目的前提下，学校可以公布论文的部分或全部内容。 作者签名：日期： 学位论文原创性声明 本人郑重声明：所呈交的论文是本人在导师的指导下独立进行研究所取得的研究成果。除了文中特别加以标注引用的内容外，本论文不包含任何其他个人或集体已经发表或撰写的成果作品。对本文的研究做出重要贡献的个人和集体，均已在文中以明确方式标明。本人完全意识到本声明的法律后果由本人承担。 作者签名：日期：年月日 学位论文版权使用授权书 本学位论文作者完全了解学校有关保留、使用学位论文的规定，同意学校保留并向国家有关部门或机构送交论文的复印件和电子版，允许论文被查阅和借阅。本人授权大学可以将本学位论文的全部或部分内容编入有关数据库进行检索，可以采用影印、缩印或扫描等复制手段保存和汇编本学位论文。 涉密论文按学校规定处理。 作者签名：日期：年月日 导师签名：日期：年月日 专门找了几个例子，让大家看看。自己也一边学习。 分析一个电源，往往从输入开始着手。220V交流输入，一端经过一个4007半波整流，另一端经过一个10欧的电阻后，由10uF电容滤波。这个10欧的电阻用来做保护的，如果后面出现故障等导致过流，那么这个电阻将被烧断，从而避免引起更大的故障。右边的4007、4700pF电容、82KΩ电阻，构成一个高压吸收电路，当开关管13003关断时，负责吸收线圈上的感应电压，从而防止高压加到开关管13003上而导致击穿。13003为开关管(完整的名应该是MJE13003)，耐压400V，集电极最大电流1.5A，最大集电极功耗为14W，用来控制原边绕组与电源之间的通、断。当原边绕组不停的通断时，就会在开关变压器中形成变化的磁场，从而在次级绕组中产生感应电压。由于图中没有标明绕组的同名端，所以不能看出是正激式还是反激式。 不过，从这个电路的结构来看，可以推测出来，这个电源应该是反激式的。左端的510KΩ为启动电阻，给开关管提供启动用的基极电流。13003下方的10Ω电阻为电流取样电阻，电流经取样后变成电压(其值为10*I)，这电压经二极管4148后，加至三极管C945的基极上。当取样电压大约大于1.4V，即开关管电流大于0.14A时，三极管C945导通，从而将开关管13003的基极电压拉低，从而集电极电流减小，这样就限制了开关的电流，防止电流过大而烧毁(其实这是一个恒流结构，将开关管的最大电流限制在140mA左右)。 变压器左下方的绕组(取样绕组)的感应电压经整流二极管4148整流，22uF电容滤波后形成取样电压。为了分析方便，我们取三极管C945发射极一端为地。那么这取样电压就是负的(-4V左右)，并且输出电压越高时，采样电压越负。取样电压经过6.2V稳压二极管后，加至开关管13003的基极。前面说了，当输出电压越高时，那么取样电压就越负，当负到一定程度后，6.2V稳压二极管被击穿，从而将开关13003的基极电位拉低，这将导致开关管断开或者推迟开关的导通，从而控制了能量输入到变压器中，也就控制了输出电压的升高， 电力电子技术课程设计说明书题目：手机充电器的设计与制作 学生姓名：李羊飞 学号： 2 院（系）：电气与信息工程学院 专业：自动化 指导教师：康家玉 2014 年 01 月 01 日 1 选题背景 1.1设计说明 本充电器由电源变压器T（8VA,9V）、整流桥堆UR(2A,50V)、三端可调 集成稳压器IC(W7805)，晶体管V1(9013E)，发光二极管VL1(RED)，电阻R1、R2，电位器RP1、RP2、RP3等组成，可对手机锂电池进行充电，电池充满电 后可自动停充。 1.2 指导思想 手机充电器输入端输入220V、50HZ电，分别经过降压、整流、滤波电路使得高电压交流电变换为低电压直流电，再分别经过分压，稳压电路实现满足 要求的电压和电流供应，完成充电过程，显示电路用于实现充电过程与充满状 态的显示。 1.3 技术要求 通信技术的高速发展促使手机种类众多，也导致手机充电器也是多种多样，本设计设计并制作一套手机通用锂电池的充电器。 技术要求：能够顺利为锂电池充电，有必要的显示、保护功能，充电电压4.2V，充电限制电压4.5V。 1.4 方案论证 从课题上可以看出设计的主体要求是将市电变换为符合要求的直流电源， 整体上应该有降压、整流、滤波、恒压电路。 降压电路可以用最简单的变压器完成，将220V电压变为10V左右的低压，为了优化波形使其更加稳定可采用滤波电容去除高频干扰。 手机通用的锂电池充电电压为4.2V，因此需要设计一个恒压源电路。充电电流在一定程度上影响了充电的时间，过高的电流会缩短电池的使用寿命，所 以我们还需要一个可靠地恒流源来保证充电的时间和手机的使用寿命。 当上述条件都具备时对于不同容量的手机电池充电时间是不一样的，因此需要 一个不以时间为参考的充电完成信号，我们可以根据电池两端的电压是否达到 标准电压来判断是否充满电。 1.4.1 方案一 本方案采用的是现行手机充电器的通用电路，主要是由开关电源和充电电路组成的。 电路图如下。 图3.1原理图 制作成功后该充电器能自动识别电池极性，自动调整输出电流使得电池达 到最佳充电状态，可保护电池延长电池寿命。充电饱和时七彩灯会自动熄灭。 当接入电源后，通过整流二极管VD1、R1给开关管Q1提供启动电流，使 Q1开始导通，其集电极电流Ic在L1中线性增长，在L2中感应出使Q1基极为正，发射极为负的正反馈电压，使Q1很快饱和。与此同时，感应电压给C1 充电，随着C1充电电压的增高，Q1基极电位逐渐变低，致使Q1退出饱和区，Ic开始减小，在 L2中感应出使Q1基极为负、发射极为正的电压，使Q1迅速 摘要 前言 一、塑件工艺分析 1.1塑件设计要求................................................... 1.2塑件生产批量要求............................................... 1.3塑件的成型要求................................................. 1.4丙烯腈-丁二烯-苯乙烯共聚物（ABS）.............................. 1.5材料的确定及相关参数........................................... 二、基本结构 2.1、模具的成形方法................................................ 2.2、型腔的布置.................................................... 2.3选择浇注系统................................................... 2.4冷却系统的设计................................................ 2.5确定推出方式................................................... 2.6侧向抽芯机构................................................... 2.7模具的结构形式................................................. 三、模具设计的有关计算 3.1注射机的选择 3.2、模具成形尺寸设计计算 四、注塑机参数校核 4.1最大注射量校核................................................. 4.2锁模力校核..................................................... 4.3模具与注塑机安装部分相关尺寸校核............................... 4.4模具闭合高度校核............................................... 4.5开模行程校核................................................... 4.6模具结构、尺寸的设计计算....................................... 4.7型腔结构....................................................... 4.8型芯结构....................................................... 4.9导向机构....................................................... 4.10复位杆........................................................ 4.11拉料杆........................................................ 4.12推件杆........................................................ 4.13推出结构...................................................... 五、塑料注射模具技术要求及总装技术要求 5.1零件的技术要求................................................. 5.2总装技术要求及装配图........................................... 结论 致谢 参考文献 恒流恒压充电器的原理与设计 2009-09-22 09:26 随着高新电子技术的发展各类充电电子产品不断上升，为此云峰电子为朋友们提供些相关恒流充电器的制作与原理分析，请仔细阅读！详情咨询https://www.wendangku.net/doc/0a7910550.html, 第一类、lm317恒流源电路图 图１、图２分别是用７８××和ＬＭ３１７构成的恒流充电电路，两种电路构成形式一致。对于图１的电路，输出电流Ｉｏ＝Ｖｘｘ／Ｒ＋ＩQ，式中Ｖｘｘ是标称输出电压，ＩQ是从ＧＮＤ端流出的电流，通常ＩQ≤５ｍＡ。当ＶＩ、Ｖｘｘ及环境温度变化时，ＩＱ的变化较大，被充电电池电压变化也会引起ＩQ的变化。ＩQ是Ｉｏ的一部分，要流过电池，ＩQ的值与Ｉｏ相比不可忽略，因而这种电路的恒流效果比较差。对于图２的电路，输出电流Ｉｏ＝ＶREF／Ｒ＋ＩADJ，式中ＶREF是基准电压，为１．２５Ｖ，ＩADJ是从调整端ＡＤＪ流出的电流，通常ＩADJ≤５０μＡ。虽然ＩADJ也随ＶI及环境条件的变化而变化，且也是Ｉｏ的一部分，但由于ＩADJ仅为７８××的ＩQ的１％，与Ｉｏ相比，ＩQ可以忽略。可见ＬＭ３１７的恒流效果较好。 对可充电电池进行恒流充电，用三端稳压集成电路构成恒流充电电路具有元件易购、电路简单的特点。有些读者在设计电路时采用７８××稳压块，如《电子报》２００１年第２期第十一版刊登的《简单可靠的恒流充电器》及今年第６期第十版的《恒流充电器的改进》一文，均采用７８０５。７８××虽然可接成恒流电路，但恒流效果不如ＬＭ３１７，前者是固定输出稳压ＩＣ，后者是可调输出稳压ＩＣ，两种芯片的售价又相近，采用ＬＭ３１７才是更为合理的改进。 ＬＭ３１７采用Ｔ０－３金属气密封装的耗散功率为２０Ｗ，采用ＴＯ－２２０塑封结构的耗散功率为１５Ｗ，负载电流均可达１．５Ａ，使用时需配适当面积的散热器。由于ＬＭ３１７的ＶREF＝１．２５Ｖ，其最小压差为３Ｖ，因此输入电压ＶI达４．２５Ｖ就能正常工作。但应注意输出电流Ｉｏ调得较大时，输入电压ＶI的范围将减小，超出范围会进入安全保护区工作状态，使用时可从图３的安全工作区保护曲线上查明输入—输出压差（ＶI－Ｖｏ）的范围。 ７８××与ＬＭ３１７内部均有限流、过热保护功能，后者还有安全工作区保护功能。７８××不允许ＧＮＤ端悬空，否则器件极易损坏。ＬＭ３１７即使ＡＤＪ端悬空，各种保护功能仍然基于单片机智能充电器的设计课程设计报告
基于单片机的电动车智能充电器的设计
基于单片机的太阳能充电器的设计毕业设计(论文)
手机充电器电路设计[1]
智能充电宝报告
智能充电器设计参考资料APPlication note
手机充电器课程设计报告
锂离子电池智能充电器硬件方案
锂电池充电器的设计毕业设计
手机充电器电路原理图分析
电力电子手机充电器课程设计方案报告
手机充电器外壳毕业设计
恒流恒压充电器的原理与设计
- 基于51单片机的智能充电器的设计
- 锂离子电池智能充电器硬件方案
- 智能充电器设计
- 基于单片机的智能充电器
- 智能充电器设计_毕业设计论文
- 智能充电器的设计(毕业设计方案)
- 智能充电器的设计.
- 智能充电器设计参考资料APPlication note
- 手机充电器设计报告
- 可编程智能充电器设计实现分析
- 智能充电器的设计
- 基于单片机的智能充电器硬件设计_闫艳霞
- 论文—智能电池充电器的设计-精品
- 基于单片机的电动车智能充电器的设计
- 智能稳压充电器的设计与制作PPt28
- 智能充电器的设计(毕业设计)
- 电池充电器设计总结(资料很全的噢)汇总
- 毕业设计_基于MAX1898的智能充电器设计
- 智能充电器设计
- 智能充电器课程设计