DATASHEET and Circuit Diagram

A theory related on DC Motor Speed Controller includes the speed control application circuits are described in the following document. In order to take a signal representing the demanded speed, and to drive a motor at that speed, a motor speed controller is needed.

What you will find in the depth of the document are sections such as Theory of DC motor speed control, The action of inductive loads, and inductors, PWM frequency, Choosing a frequency based on motor characteristics, Speed control circuits, Regenerative Braking Circuit, Reversing DC Motor, The Full Bridge Circuit, Generating PWM signals (using 74HC14, 74HC163, LM324), Current limiting circuit, and Feedback Speed Control.

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This datasheet contains information related to L9407F Voltage Regulator from STMicroelectronics which is a monolithic multifunction device intended for use in automotive application. You may see the L9407F application schematic diagram below.

The L9407F Car Alternator Voltage Regulator features Low side field driver, Thermal protection, Field short circuit protection, Protected diagnostic lamp driver, Protected high side relay driver, Complex diagnostics, Load response control, and Fully monolithic design, according to the datasheet.

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LM2700 step-up PWM DC/DC converter is an ideal part for biasing LCD displays. It features internal switch, pin selectable frequency for easy filtering and low noise, over temperature protection circuit and adjustable output voltage up to 17.5V. It used to be applied on applications such as handheld, GSM/CDMA Phones, digital cameras and portable applications.

Find sections such the typical application circuit, 14-Lead TSSOP or LLP package connection diagram, pin description, operation circuit example of LM2700 (continuous conduction mode, setting the output voltage, DC gain and Loop gain, inductor and diode selection, input and output capcitor selection, and etc), and the application circuit information related to the operation functions in the datasheet.

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The article herein describes information on how voltage controlled oscillator (VCO) buffer may isolate oscillator circuit’s output problems. The VCO buffers which being used are MAX2472/2473 from Maxim Semiconductor. It discussed issues related to VCO circuits such as load pulling, supply pushing, phase noise and effects of radiated energy from nearby power amplifiers (PAs).

You will be taken into discussion on introducing a buffer amplifier between two isolated circuit stages, typical VCO characteristics and how isolation problems can degrade circuit performance, A Typical BJT Based Colpitts VCO, MAX2472 isolation circuit between VCO and mixer, and more.

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The herein article contains information related on the method of closed loop control with a sensor and an actuator and how to apply the method to build a rudimentary On/Off heater controller (On/Off Temperature Control). The semiconductor components used to build this control circuit are thermistor, Zener diode, LED, relay, op-amp, and bipolar transistor.

Sections describe in this article are such essential elements of the control circuit, basic thermistor sensing circuit (using an op-amp without feedback as a comparator), thermistor sensing circuit using 2N222 transistor with 4 and output driver stage added, controlling a real actuator with a relay, and then finalising the circuit and improving the stability with Schmitt Trigger.

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The following document contains information related to Volvo 440 electrical installation schematic diagram. It such the wiring schematic for Volvo 440, 460, and 480 series.

What you will find in the depth of the document are the typical wiring diagram for 1991 Volvo 440/460 models, wiring diagram for the B18E/B18F/B18FT/ Engine of the same vehicle, anti-lock braking system (ABS) wiring diagram for the 1991 and 1992 440/480 models, the typical wiring of 1992 440/480 models and etc.

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The herein schematic shows FAN5009 dual bootstrapped 12V high frequency MOSFET driver typical application circuit. It can be formed a complete core voltage regulator for microprocessors if combined with multi-phase PWM controller and power MOSFETs, according to the FAN5009 datasheet.

Related to the application schematic, these drivers can be applied as Supply Capacitor Selection, Bootstrap Circuit, Low and High Side Driver, and Adaptive Gate Drive Circuit.

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This SSL2102 LED Driver IC is designed to drive LED devices, such a main IC for dimmable LED lighting. This device is categorized as a Switched Mode Power Supply (SMPS) controller IC which has high-voltage circuitry to supply the phase cut dimmer.

The diagram above shows SSL2102 LED Driver Application Example Circuit Design. It is suitable for high efficiency and high power factor SSL applications such as SSL retro-fit lamps, LED spots, LED strings and more.

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This document may help you understanding the bootstrap circuitry since it contains such information related. A bootstrap circuit is an arrangement of components used to boost the input impedance of a circuit by using a small amount of positive feedback, usually over two stages (wikipedia.org).

What you will read in this document are sections describe Operation Of The Bootstrap Circuit, Influencing Factors Affecting The Bootstrap Supply, Calculating The Bootstrap Capacitor Value, How to Select The Bootstrap Diode, and Recommended Layout of the Bootstrap Components (Layout Considerations).

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The basic structure to create a current boosting switch using an NPN transistor is shown in this circuit diagram. Current boosters are needed to step up the current to an adequate level needed by the high current and high voltage circuits.

The following article will demonstrate ways to uses transistors as current boosting switches. You will find informations related to microprocessors and IC’s with the transistors, saturating the right transistor (step-by-step process to choosing the right transistor), and simulation examples. Thus, this article offers tools and techniques to boost the current while maintaining the functionality of circuit system.

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