The role of a voltage regulator is to convert an unstable DC voltage into a stable DC voltage. However, the integrated voltage regulator has a wider and wider range of applications due to its advantages such as small size, good voltage regulation performance and perfect maintenance function. There are two types of integrated regulators: linear power regulators and switching power supply regulators. Since switching power supply regulators are classified as analog and digital hybrid circuits, we will introduce such regulators later, and only analog integrated regulators will be introduced below. Analog integrated regulators are available in three-terminal and multi-terminal versions.
(1) Three-terminal regulator
The three-terminal regulator is divided into two types: non-adjustable and adjustable.
(1) The regulator cannot be adjusted at three ends. The three-terminal non-regulator is the most widely used regulator at present. There are two main types of three-terminal non-adjustable regulators: 78×× series and 79×× series. In the meantime, the 78×× series regulators output a positive voltage, while the 79×× series regulators output a negative voltage.
a. Classification. The three-terminal non-regulating regulator can be divided into 10 kinds according to the output voltage, taking the 78×× series regulator as an example, including 7805 (5V), 7806 (6V), 7808 (8V), 7809 (9V), 7810 (10V), 7812 (12V), 7815 (15V), 7818 (18V), 7820 (20V), 7824 (24V), and the three-terminal non-regulating regulator can be divided into many kinds according to the output current.
b. The operating principle of the three-terminal non-adjustable regulator. The following takes the 78×× series three-terminal non-regulating regulator as an example to introduce the operating principle of the three-terminal non-regulating regulator. The 78×× series three-terminal non-regulating regulator is composed of a starting circuit (constant current source), a sampling circuit, a reference voltage composition circuit, an error amplifier, an adjustment tube, and a maintenance circuit.
When there is a normal power supply voltage input at the input terminal of the 78×× series three-terminal non-regulating regulator, the voltage is not only added to the collector of the adjustment tube, but also passes through the reference voltage to form the circuit reference voltage. After the reference voltage is added to the error amplifier, the error amplifier supplies the reference voltage to the base of the adjustment tube, so that the emitter output voltage of the adjustment tube is limited by R1, and then outputs through the output terminal of the three-terminal non-regulating regulator to supply power to the load.
When the input voltage drops or the load becomes heavier, causing the output voltage Uo of the three-terminal unregulated regulator to drop, the voltage decreases after sampling by the adjustable resistors RP and R2. The voltage is added to the inverting input of the error amplifier, and after comparing with the reference voltage of the input at the non-inverting input, the output voltage increases, and the conduction degree of the adjustment tube is strengthened due to the increase of the base input voltage, so that the Uo rises to the specified value and completes the voltage stabilization control. When the output voltage increases, the regulation process is reversed.
When the load is abnormal, the overcurrent of the adjustment tube is detected by the overcurrent maintenance circuit, and the adjustment tube stops the operation to prevent the overcurrent damage of the adjustment tube and completes the overcurrent maintenance. In addition, when the overcurrent of the adjustment tube is overcurrent, the temperature will rise significantly, and after being detected by the overheating maintenance circuit in the chip, the adjustment tube will also stop working, preventing the overheating damage of the adjustment tube and completing the overheating maintenance.
(2) Three-terminal adjustable voltage regulator. The three-terminal adjustable regulator is developed on the basis of the three-terminal non-adjustable regulator, and its biggest advantage is that the output voltage can be continuously adjusted within a certain range. Like the three-terminal non-regulating regulator, it also has a positive voltage output and a negative voltage output.
a. Classification. The three-terminal adjustable regulator can be divided into 4 types according to the output voltage: the first is the output voltage of 1.2-15V, such as LM196/396; the second is the output voltage of 1.2-32V, such as LM138/238/338; The third is the output voltage of 1.2-33V, such as LM150/250/350; The fourth is the output voltage of 1.2-37V, such as LM117/217/337.
The three-terminal adjustable regulator is divided into 0.1A, 0.5A, 1.5A, 3A, 5A, 10A and other types according to the output current. The output current of a regulator with the letter "L" after the regulator type is 0.1A, for example, LM317L is a regulator with a maximum current of 0.1A; The output current of the regulator with the letter "M" after the regulator type is 0.5A, for example, the LM317M is the regulator with a maximum current of 0.5A; The output current of a regulator without a letter after the regulator type is 1.5A, such as the LM317, which is a regulator with a maximum current of 1.5A. The LM138/238/338 is a 5A regulator and the LM196/396 is a 10A regulator.
b. Principle of operation. The three-terminal adjustable voltage regulator consists of a constant current source (engine circuit), a reference voltage constituent circuit, a regulator (adjustment tube), an error amplifier, and a maintenance circuit.
When there is a normal supply voltage input at the input of the voltage regulator LM317, the voltage not only supplies power to the regulator, but also supplies the reference voltage to the reference amplifier through a constant current source, and the reference voltage is generated by it. When the reference voltage is added to the non-inverting input of the error amplifier, the error amplifier supplies the on-voltage to the regulator, so that the output voltage at the beginning of the regulator is supplied to the load after the output voltage is output through the output terminal.
When the input voltage decreases or the load becomes heavier, causing the output voltage of LM317 to drop, the input voltage of the inverting input terminal of the error amplifier decreases, the voltage supplied by the error amplifier to the regulator increases, and the output voltage of the regulator increases, and finally the output voltage rises to the specified value to complete the voltage stabilization control. When the output voltage rises, the regulation process is reversed.
The output voltage of the 1.25V reference circuit in the LM317 is controlled by the input voltage of the ADJ at the regulator terminal, and when the input voltage of the ADJ terminal increases, the output voltage of the reference voltage constituent circuit increases, and the output voltage of the error amplifier increases due to the increase of the voltage at the non-inverting input terminal, which increases the output voltage of the regulator. Conversely, the process of manipulation is reversed. In this way, the output voltage of the LM317 can also be changed by adjusting the voltage of the ADJ terminals.
|
More on that
|
德力西断路器P数选择要点
关于微型断路器来说,1P+N、1P、2P一般都用来作为单相用电器的通断操控,但作用不同。为了便于用户的挑选及差异,特在此对断路器P数的差异及挑选方法进行简单的分析。
...
|
|
德力西变频器的启动、停止如何接线
变频器的操控,不外乎启动,中止,正转,回转,调速这几样基本的逻辑,这些逻辑基本上要求是电平状况有用,而不是上升边际有用,所以运用按钮开关操控变频器的时分,一般需要运用自保形式的按钮 ...
|
|
德力西均分器的产品特点
1、均分器是采用微电脑芯片的第六代智能机,智能化程序十分高。
2、单相三相任部接,市面上的均分器对于三相电都得分为A、B、C三相接线,不只装置不方便,也容易呈现相序错误。
3、可 ...
|
|
变频控制方式的变迁——德力西变频器
在实践调速过程中,一个普通的频率可调的沟通电源并不能满足对异步电动机进行调速操控的要求,还必须考虑到有效使用电动机磁场、抑制发动电流和得到抱负的转矩特性,如低频转矩特性等方面的问题 ...
|
|
德力西交流接触器故障原因及解决方法
一、铁芯吸合不上或许吸力缺乏
原因:电源电压过低或波动过大,操作回路电源容量缺乏或产生断线及控制触头接触不良,线圈技术参数与运用条件不符,产品本身损坏。
解决方法:调高电源 ...
|
|
德力西时控开关调节方法
先按撤销功能键,再按住校时功能键,接着把时刻和日期调整到当下的时刻,再次按守时功能键,把需要关闭和敞开的时刻调整到指定的数值,要是需要设置多组的话,就接着按守时功能键设置,不用多组 ...
|
|
Electrical appliances need voltage regulators for reasons
Typically, every electrical device or device is designed for a wide range of input voltages. Depending on the sensitivity, the operating scale of the device is constrained to a specific value, for example, some devices can tolerate ±10% of the additional voltage, while others can tolerate ±5% or less.
...
|
|
变频器的构造——德力西
主电路是给异步电动机供给调压调频电源的电力变换部分,变频器的主电路大体上可分为两类:电压型是将电压源的直流变换为沟通的变频器,直流回路的滤波是电容。电流型是将电流源的直流变换为沟通 ...
|
|
Delixi molded case circuit breaker external two tripping wire connection
The molded case circuit breaker tripper is divided into undervoltage tripper and shunt tripper. This article explains the wiring method of the circuit breaker with sub-excitation tripper. The shunt tripper is often used as an additional accessory for the user, it is a remotely operated circuit breaker disconnection device, installed in the molded case circuit breaker, when the shunt ...
|
|
The cause of the failure of Delixi inverter
1. Overcurrent (short circuit)
Overcurrent problems are the most common in the side of various faults in the inverter. The problem is mostly due to the following problems: first, as long as the speed converter is reported when starting, it is clear that the overcurrent is very serious, and most of them are load short circuits, mechanical parts stuck, inverters...
|
|
Delixi circuit breaker product characteristics classification
The function of Delixi circuit breaker is to make the circuit breaker internal electromagnetic tripping when the electrical equipment produces short circuit, overload, etc., resulting in the circuit breaker disconnecting the power supply, and maintaining the safety of electrical equipment and personnel.
When the electrical equipment is running, the circuit may produce abnormalities, which is the demand circuit breaker in the ...
|
|
德力西LDO与DC-DC的差别
所谓DC-DC其实便是直流变直流电压,当然LDO也算是DC-DC的一种,仅仅LDO只能实现降压。
一般的DC-DC首要内部经过自激振动电路先由DC转成AC沟通,所以外面需求电感和电容实现LC振动(而LDO只 ...
|
|
德力西DZ47LE C40空气开关介绍
一般的漏电断路器都是采用进步线下出线的原则来接线的,只需分清相线和零线就能够,注间,零线上是标有N的就对了,进出线都是一样的。
德力西DZ47LE C40空 ...
|
|
变频器短路故障特点判断及处理——德力西
(1 )故障特色
a )第一次跳闸有可能在运转过程中产生,但如复位后再起动,则往往一升速就跳闸。
b )具有很大的冲击电流,但大多数变频器现已能够进行维护跳闸,而不会损坏。由于维 ...
|
|
隔离开关和断路器区别
断路器有灭弧设备,故断路器能够带负荷操作,不但能操作负荷电流,还能操作毛病(短路)电流;断路器有良好的封装形式,故单纯观察断路器,不能直观地确定其是处在闭合或断开方位。
隔离开 ...
|
|
Problems in the installation and use of Delixi voltage regulator
What is the voltage regulator can not be connected in parallel, the voltage regulator is not open for a long time, what will be the problem with the voltage regulator still open under normal voltage, is it said that the voltage regulator and the undervoltage lamp is not lit to clarify that the voltage regulator is normal?
Will a normally open regulator burn it out at normal voltage?
...
|
|
减少变频器维修次数方法——德力西
变频器是现代化工场中一个使用很是遍及的设备,这是一种新型设备,价钱很是高贵,并且变频器修理的价钱也很是贵,所以在使用变频器的过程中,留意变频器的使用方式,一方面是变频器,耽误变频器 ...
|
|
德力西变频器控制器的数据跑飞如何解决
问题描绘:
德力西变频器控制器的数据跑飞,或数据偶然不正确,如何解决?
解决方法:
此种情况是控制器受到严峻的搅扰所造成的。往往 ...
|
|
德力西继电器的检修方法
继电器是一种依据外界输入的信号,如电气量(电压、电流)或非电气量(热量、时间、转速等])的变化接通或断开操控电路,以完结操控或维护使命的电器,它有三个基本部分,即感测组织、中心组织和执 ...
|
|
Delixi circuit breaker model difference
CDB1 miniature circuit breaker is a kind of current-limiting high-breaking miniature circuit breaker with double protection of overload and short circuit, which is suitable for AC 50Hz, rated voltage 400V and below, rated current 63A and below circuits, as line overload and short circuit protection, can also be used under normal circumstances.
|
|