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Car Emergency Starter Principle


Generally the car emergency starter Factory do not have the core product technology,the battery and the battery cell are assembled and integrated programs,so these products are uncompetitive in the market.MAIRPOWER Car jump starter is totally different from other manufacturers in this area,We got our own polymer production division,has own PCBA  board R&D department.Currently car emergency starter sale increased as 30% per month speed straightly,a steady increase in the market.After half a year in October the wather become cooler gradually,car emergency starter will continue to hot on sale in the market.

1.The input voltage VIN Range: 12V battery voltage transient range determines the power conversion IC input voltage range of a typical car battery battery voltage range of 9V to 16V, when the engine is turned off, the car battery battery nominal voltage of 12V; engine in operation, the battery voltage of about 14.4V. However, under different conditions, the transient voltage may reach ± 100V. ISO7637-1 industry standard defines the voltage fluctuation range of automotive batteries. Part of the waveform shown in FIG. 1 and FIG. 2 is the ISO7637 standard waveform given, showing a high-voltage power converter car need to meet the critical condition. In addition to ISO7637-1, there are some definitions for the gas engine operating range and battery conditions. Most of the new guidelines were developed by different car manufacturers made the emergency start power supply, do not necessarily follow the industry standard,However, any new standards as long as it comes to automotive safety systems require overvoltage and undervoltage, anti-kickback protection.

2.Heat Dissipation Considerations:heat dissipation needs based on the lowest efficiency DC-DC converters desigened.Air circulation is poor or no ventilation applications,if the ambient temperature is high (> 30 ° C), the presence of shell heat (> 1W), Equipment will quickly fever (> 85 ° C). For example, most of the audio amplifier needs to be installed on the heat sink, and the need to provide good air circulation to dissipate heat conditions. In addition, PCB materials and certain copper area will help to improve the heat transfer efficiency, so as to achieve the best cooling conditions. If you do not use the heat sink, cooling capacity on the exposed pad package is limited to 2W to 3W (85 ° C). As the ambient temperature rises, the cooling capacity will be significantly reduced. The battery voltage into low voltage (eg: 3.3V) output linear regulator will 75% of the input power loss, low efficiency. In order to provide 1W output power, there will 3W power consumed as heat. Limit the ambient temperature and case / junction resistance by, it will significantly reduce the maximum output power of 1W. For most of the high-voltage DC-DC converter, the output current at 150mA to 200mA range, LDO can provide a higher cost. The battery voltage into low voltage (eg: 3.3V), when the power of 3W, the need for high-end switching converters, this converter can provide more than 30W output power. This is why car manufacturers usually use switching power supply solutions, to the exclusion of traditional architecture based on reason.

3. The quiescent current and the off current with the vehicle electronic control unit (ECU) the number of rapid growth, the total current from the car battery consumption is also growing. Even when the engine is turned off and the battery is depleted, some ECU unit remains active. In order to ensure the quiescent current IQ in the controllable range, most OEM manufacturers began to restrict the IQ of each ECU. Such as requiring the EU are: 100μA / ECU. The vast majority of EU car standard IQ typical ECU below 100μA. Always keep working devices,DMOZ Free Directory Submission such as: the current consumption CAN transceiver, real-time clock and microcontroller is a major factor to consider ECU IQ, power supply design needs to consider a minimum IQ budget.

4.Cost control: OEM manufacturers to the cost and size of compromise is an important factor in the bill of materials, for mass production of products, the cost is an important factor to be considered in the design. PCB type, cooling capacity, allows the selection of packaging and other design constraints actually limited to a specific project budget. For example, using a 4-layer and single-layer FR4 board CM3, there is a great difference between PCB cooling capacity will be. Project budget constraints will lead to another, the user can accept a higher cost of ECU, but will not spend time and money to transform the traditional power supply design.For the high cost of some new development platform, designers simply not optimized for traditional power design some simple repair and maintain.

5.Position/layout:in power supply design PCB and component placement will limit the power of the overall performance of the structural design, circuit board layout, noise sensitivity, multilayer interconnect problems, and other layout constraints will limit the high power chip design .The Free Directory UK British orientated web site links The use of point of load power to generate all the necessary power will lead to high costs, the number of components on a single chip set is not ideal. Power supply designers need, depending on the project needs Seeking to balance the overall system performance, mechanical constraints and cost.

6.The electromagnetic radiation: electric radiation field will produce electromagnetic radiation with time-varying,the radiation intensity depends on the frequency and amplitude of the field, an electromagnetic interference generated by the operation of the circuit will directly affect the other circuit.Free Website Directory For example, may cause interference with radio channels airbag malfunction, in order to avoid these negative effects, car emergency start against the ECU unit power supply manufacturers developed a maximum limit of electromagnetic radiation.WWWi.co.uk To keep the electromagnetic radiation (EMI) in a controlled range, DC-DC converter type, topology, peripheral component selection, board layout and shielding are very important. Over the years, power IC designers developed a variety of techniques to limit EMI. External clock synchronization, higher operating frequency band AM modulation, built-in MOSFET, soft-switching technology, spread spectrum techniques are expensive too good technology introduced in recent years EMI suppression scheme.

Quality is our life and soul,MAIRPOWER will make the best quality car jump starter with afforable price to thank all customer's support.