DATASHEET and Circuit Diagram

Herein is an example of a simple, low cost and flexible battery charger circuit using micropower linear voltage regulator device, ADM666A from Analog.

In the ADM666A application note, you can find detailed explanation about this low cost battery charger circuit such as Maximum output voltage, Charge termination voltage calculation, monitoring the battery voltage level, maximizing the circuit efficiency, and etc.

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Here we provide you with a semiconductor article regarding the power MOSFET (metal Oxide Semiconductor Field Effect Transistor). This device used in a wide range applications such as SMPS, computer peripherals, automotive, and motor control. You will find a general description about power MOSFETs inside the article.

What will be described by the article are sections such as History of Power MOSFETs, types of field effect transistors, The Structure of a MOSFET (lateral and vertical channel design), The Characteristics of a MOSFET (advantages, disadvantages, and basic characteristics), Characteristics of MOSFET’s in ON and OFF States, and user’s manual.

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Battery backup and battery charging are two modes of battery backup circuits. The circuit below shown a simple battery backup circuit using low treshold MOSFET device in order to gain better efficiency in addition of very low voltage drop resulted by the MOSFETs that will prolong battery life, and meet battery voltage limitations.

You require the following component selection to design this Battery Backup Circuit : 1N4001 Diodes (D1-D5), standard 1/4 watt, 5% tolerance Resistors, dual comparator LM393N for U1, 5 Eveready nickel cadmium cells battery in series, and TN0604N3 low threshold N-channel DMOS transistors for their low on-resistance at low gate drive. You can modify this circuit with an added features such as battery backup mode indicator, low battery voltage early warning, or battery shutdown indicator with a microprocessor in more complex systems.

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Stepper motors have two types, unipolar and bipolar. In unipolar motors the current flows one direction through any given motor coil while motor need controllers to adjust position and speed. Then you will need a motor driver to amplify a controller’s low output current to a larger current that is required by a motor. Below is an article that describe you about how to design a unipolar stepper motor controller/driver.

You will be taken into sections that will describe you on unipolar stepper motor and BJT transistors, learn how to use a universal shift register, and put it altogether to design unipolar stepper motor driver (using a Jameco 15 V unipolar stepper motor). Within the article, there are explanation about The advantages and disadvantages between unipolar, bipolar and DC motors, Ways of energizing stepper motor coils in the proper sequence, Variable Speed Stepper Motor Drive, and Microcontroller Stepper Motor Control.

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The CS3341 IC’s series from Cherry Semiconductor are designed for use in alternator charging system particularly the CS3341 and CS3351. This device drives an external power Darlington for controlling the alternator field current and provides 3-phase alternators-the voltage regulation for automotive.

The circuit diagram shows you a typical application of The CS3341 IC’s series. The oscillator frequency is set by an external capacitor connected between OSC and ground. According to the datasheet, the alternator voltage is sensed at Terminal A via the resistor divider network R1/R2 on the Sense pin of the IC. Voltage at sense pin means the duty cycle for the regulator and adjusted by potentiometer R2. The Lamp pin goes high when an overvoltage is detected on sense pin and make the darlington lamp drive transistor to switch on and pull current through the lamp.

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If you need a voltage regulator designed primarily for series regulator applications you may consider National LM723/723C voltage regulator. This device is used to be applied in a wide range applications such as shunt regulator, current regulator and/or temperatur controller.

This LM723/723C voltage regulator will supply output currents up to 150mA without external pass transistor, but if you desire any load current you can add an external transistors on it which will drive output currents in excess of 10A possible. LM723?723C has 40V max of input voltage with an adjustable output voltage range from 2V to 37V, according to the datasheet.

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