Small FM Receiver Circuit

This is the most simple fm radio receiver with good performances that works great even if the sensitivity is not too high. The working principle of this fm receiver may seem a little unusual. It is made of an oscillator (T2 and T3) that is synchronized with the received frequency of T1. This transistor works as a broadband preamplifier in VHF range.

The oscillator is adjusted between 87 … 108 MHz with C5. Because of the synchronization, the oscillator output will have the same frequency deviation as the received signal from the fm antenna. This deviations are caused by the broadcasted audio informations. The frequency modulated signal show up on P1 + R5. Low pass filter R6/C6 extracts the audio signal and then is amplifier by T4 … T6 and transmitted at the output through C9 capacitor.

FM Receiver Circuit Diagram

The coil details are presented in the fm receiver circuit diagram. The radio receiver is adjusted on different stations with the help of C5. P1 potentiometer is adjusted untill the best reception is obtained. If we attach an audio amplifier and a speaker then this fm receiver can be made very compact as a pocket radio.

source : http://electroschematics.com/4663/small-fm-receiver/

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Long Range FM Transmitter Circuit Diagram

The power output of most of these circuits are very low because no power amplifier stages were incorporated.
The transmitter circuit described here has an extra RF power amplifier stage, after the oscillator stage, to raise the power output to 200-250 milliwatts. With a good matching 50-ohm ground plane antenna or multi-element Yagi antenna, this transmitter can provide reasonably good signal strength up to a distance of about 2 kilometres.

The circuit built around transistor T1 (BF494) is a basic low-power variable-frequency VHF oscillator. A varicap diode circuit is included to change the frequency of the transmitter and to provide frequency modulation by audio signals. The output of the oscillator is about 50 milliwatts. Transistor T2 (2N3866) forms a VHF-class A power amplifier. It boosts the oscillator signals’ power four to five times. Thus, 200-250 milliwatts of power is generated at the collector of transistor T2.

For better results, assemble the circuit on a good-quality glass epoxy board and house the transmitter inside an alumunium case. Shield the oscillator stage using an aluminium sheet.
Coil winding details are given below:
L1 - 4 turns of 20 SWG wire close wound over 8mm diameter plastic former.
L2 - 2 turns of 24 SWG wire near top end of L1.
(Note: No core (i.e. air core) is used for the above coils)
L3 - 7 turns of 24 SWG wire close wound with 4mm diameter air core.
L4 - 7 turns of 24 SWG wire-wound on a ferrite bead (as choke)
Potentiometer VR1 is used to vary the fundamental frequency whereas potentiometer VR2 is used as power control. For hum-free operation, operate the transmitter on a 12V rechargeable battery pack of 10 x 1.2-volt Ni-Cd cells. Transistor T2 must be mounted on a heat sink. Do not switch on the transmitter without a matching antenna. Adjust both trimmers (VC1 and VC2) for maximum transmission power. Adjust potentiometer VR1 to set the fundamental frequency near 100 MHz.
This transmitter should only be used for educational purposes. Regular transmission using such a transmitter without a licence is illegal in India.

source :  http://www.electronic-circuits-diagrams.com/radioimages/radiockt1.shtml

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How do motion sensing lights and burglar alarms work?

T­here are many different ways to create a motion sensor. For example:

• It is common for stores to have a beam of light crossing the room near the door, and a photosensor on the other side of the ­room. When a customer breaks the beam, the photosensor detects the change in the amount of light and rings a bell.
• Many grocery stores have automatic door openers that use a very simple form of radar to detect when someone passes near the door. The box above the door sends out a burst of microwave radio energy and waits for the reflected energy to bounce back. When a person moves into the field of microwave energy, it changes the amount of reflected energy or the time it takes for the reflection to arrive, and the box opens the door. Since these devices use radar, they often set off radar detectors.
• The same thing can be done with ultrasonic sound waves, bouncing them off a target and waiting for the echo.

All of these are active sensors. They inject energy (light, microwaves or sound) into the environment in order to detect a change of some sort.

The "motion sensing" feature on most lights (and security systems) is a passive system that detects infrared energy. These sensors are therefore known as PIR (passive infrared) detectors or pyroelectric sensors. In order to make a sensor that can detect a human being, you need to make the sensor sensitive to the temperature of a human body. Humans, having a skin temperature of about 93 degrees F, radiate infrared energy with a wavelength between 9 and 10 micrometers. Therefore, the sensors are typically sensitive in the range of 8 to 12 micrometers.

The devices themselves are simple electronic components not unlike a photosensor. The infrared light bumps electrons off a substrate, and these electrons can be detected and amplified into a signal.

You have probably noticed that your light is sensitive to motion, but not to a person who is standing still. That's because the electronics package attached to the sensor is looking for a fairly rapid change in the amount of infrared energy it is seeing. When a person walks by, the amount of infrared energy in the field of view changes rapidly and is easily detected. You do not want the sensor detecting slower changes, like the sidewalk cooling off at night.

Your motion sensing light has a wide field of view because of the lens covering the sensor. Infrared energy is a form of light, so you can focus and bend it with plastic lenses. But it's not like there is a 2-D array of sensors in there. There is a single (or sometimes two) sensors inside looking for changes in infrared energy.

­ If you have a burglar alarm with motion sensors, you may have noticed that the motion sensors cannot "see" you when you are outside looking through a window. That is because glass is not very transparent to infrared energy. This, by the way, is the basis of a greenhouse. Light passes through the glass into the greenhouse and heats things up inside the greenhouse. The glass is then opaque to the infrared energy these heated things are emitting, so the heat is trapped inside the greenhouse. It makes sense that a motion detector sensitive to infrared energy cannot see through glass windows.

source : http://home.howstuffworks.com/home-improvement/household-safety/security/question238.htm

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How Batteries Work

Imagine a world where everything that used electricity had to be plugged in. Flashlights, hearing aids, cell phones and other portable devices would be tethered to electrical outlets, rendering them awkward and cumbersome. Cars couldn't be started with the simple turn of a key; a strenuous cranking would be required to get the pistons moving. Wires would be strung everywhere, creating a safety hazard and an unsightly mess. Thankfully, batteries provide us with a mobile source of power that makes many modern conveniences possible.

While there are many different types of batteries, the basic concept by which they function remains the same. When a device is connected to a battery, a reaction occurs that produces electrical energy. This is known as an electrochemical reaction. Italian physicist Count Alessandro Volta first discovered this process in 1799 when he created a simple battery from metal plates and brine-soaked cardboard or paper. Since then, scientists have greatly improved upon Volta's original design to create batteries made from a variety of materials that come in a multitude of sizes.

Today, batteries are all around us. They power our wristwatches for months at a time. They keep our alarm clocks and telephones working, even if the electricity goes out. They run our smoke detectors, electric razors, power drills, mp3 players, thermostats -- and the list goes on. If you're reading this article on your laptop or smartphone, you may even be using batteries right now! However, because these portable power packs are so prevalent, it's very easy to take them for granted. This article will give you a greater appreciation for batteries by exploring their history, as well as the basic parts, reactions and processes that make them work. So cut that cord and click through our informative guide to charge up your knowledge of batteries.

source : http://electronics.howstuffworks.com/everyday-tech/battery.htm

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How Capacitors Work

In a way, a capacitor is a little like a battery. Although they work in completely different ways, capacitors and batteries both store electrical energy. If you have read How Batteries Work, then you know that a battery has two terminals. Inside the battery, chemical reactions produce electrons on one terminal and absorb electrons on the other terminal. A capacitor is much simpler than a battery, as it can't produce new electrons -- it only stores them.

In this article, we'll learn exactly what a capacitor is, what it does and how it's used in electronics. We'll also look at the history of the capacitor and how several people helped shape its progress.

Inside the capacitor, the terminals connect to two metal plates separated by a non-conducting substance, or dielectric. You can easily make a capacitor from two pieces of aluminum foil and a piece of paper. It won't be a particularly good capacitor in terms of its storage capacity, but it will work.

In theory, the dielectric can be any non-conductive substance. However, for practical applications, specific materials are used that best suit the capacitor's function. Mica, ceramic, cellulose, porcelain, Mylar, Teflon and even air are some of the non-conductive materials used. The dielectric dictates what kind of capacitor it is and for what it is best suited. Depending on the size and type of dielectric, some capacitors are better for high frequency uses, while some are better for high voltage applications. Capacitors can be manufactured to serve any purpose, from the smallest plastic capacitor in your calculator, to an ultra capacitor that can power a commuter bus. NASA uses glass capacitors to help wake up the space shuttle's circuitry and help deploy space probes. Here are some of the various types of capacitors and how they are used.

• Air - Often used in radio tuning circuits
• Mylar - Most commonly used for timer circuits like clocks, alarms and counters
• Glass - Good for high voltage applications
• Ceramic - Used for high frequency purposes like antennas, X-ray and MRI machines
• Super capacitor - Powers electric and hybrid cars

source : http://electronics.howstuffworks.com/capacitor.htm

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How to Make a Line Following Robot

Project Summary

The motors I used for this robot are 2 servomotors modified for speed. You can also use other motors if it's good enough. I didn't have any so I modded 2 servomotors.

Project Description

 Figure 1  microcontroller-schematic

How to Mod the Servomotors (look at the pictures)

• Remove the four screws from the servo and take it all apart.
• Remove the electronics keeping only the wires from the motor (I kept the other 3 wires from the potentiometer but you don’t have to).
• Try to fit the gears except for one. I glued the big gear to the one beneath it so to be high enough to “get out” of the case. It isn’t exactly a rule for how to do this. Various servos will have various gears so you will need to try until you find the best “combination”.
• Put everything together.

 Figure 2  parts

The BODY (look at the picture):

The base of the robot is made of PCB cutted to the properly size.
You will also need 5 screws:
2 for putting together the front and the base of the robot and one for lifting the sensors off the ground (you can use something else here, if you have) 2 for lifting and fixing the microcontroller PCB

 Figure 3  Line-follower

The SENSORS:

I made my sensors using 5 SMD IR emiting diodes, 5 SMD phototransistors and 5 1k SMD resistors. Between the phototransistor and the IR I put some black silicone so the IR light would not come directly to the phototransistor. The PCB design is in the archive “line follower.rar”. It is made in PROTEUS, but I have a word document including all the PCB designs which can be printed on glossy paper or Press and Peel, and then transfered to the PCB using the method of the iron.

The MICROCONTROLLER PCB:

The “heart” of this robot is an ATMEGA8 microcontroller which gets the information from the sensors and drive the L293D motor controller.
Parts list:

1× 28-pin socket (for ATMEGA8)
1× 14-pin socket (for L293)
1x ATMEGA8 – You can also use an ATMEGA 168 or 328. The program is made in Arduino , so if you have an arduino, you can program the microcontroller on it, then remove it from arduino and insert it in this PCB. Also you can program this microcontroller via the 6 pins with an ISP.
1x L293D
1× 16MHz Crystal
2× 22pF (10-28pF)
1x LM7805
1x Push Button
1× 100nF
1× 100uF
1× 4.7 uF
6x LEDs
1× 1K resistor
1× 33R resistor
1x Break Away Header
1x Straight Female Header
1x SwitchWires
Also you will need one 4 AA battery holder.

Everything you need for making the microcontroller pcb and the sensors PCB is in the “line follower.rar” archive. You will find the PCB design, and the schematics which are made in Proteus, but are also available in the Word document.

 Figure 4  The-electronics

Now all you have to do is take the soldering iron and start to solder all the parts. After you’ve assembled the robot, you need to program the microcontroller. The program is made in Arduino so you can upload it to Arduino and then put the microcontroller in this “motherboard”. You also have the HEX file for an ATMEGA8 using 16Mhz crystal.

Figure 5  Assembly

After everything is done, all you need to do is assemble the robot. You can watch a video of me assembling it. Enjoy!

Project Files

File Name	File Size
code file	2.98 KB
code file in hex format	2.98 KB
how to place component text file	48 KB
how to construct the robot is provided in this file everything step wise	556 KB
microcontroller.DSN	58.62 KB
layout	36.72 KB
pcb printing format	34 KB
sensor	60.39 KB
sensor layout	19.66 KB

source : http://www.eeweb.com/project/rinkesh_kurkure/line-follower1

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How Circuit Breakers Work

The circuit breaker is an absolutely essential device in the modern world, and one of the most important safety mechanisms in your home. Whenever electrical wiring in a building has too much current flowing through it, these simple machines cut the power until somebody can fix the problem. Without circuit breakers (or the alternative, fuses), household electricity would be impractical because of the potential for fires and other mayhem resulting from simple wiring problems and equipment failures.

In this article, we'll find out how circuit breakers and fuses monitor electrical current and how they cut off the power when current levels get too high. As we'll see, the circuit breaker is an incredibly simple solution to a potentially deadly problem.

To understand circuit breakers, it helps to know how household electricity works.

Electricity is defined by three major attributes:

• Voltage
• Current
• Resistance

Voltage is the "pressure" that makes an electric charge move. Current is the charge's "flow" -- the rate at which the charge moves through the conductor, measured at any particular point. The conductor offers a certain amount of resistance to this flow, which varies depending on the conductor's composition and size.

­Voltage, current and resistance are all interrelated -- you can't change one without changing another. Current is equal to voltage divided by resistance (commonly written as I = v / r). This makes intuitive sense: If you increase the pressure working on electric charge or decrease the resistance, more charge will flow. If you decrease pressure or increase resistance, less charge will flow.

source : http://electronics.howstuffworks.com/circuit-breaker.htm

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On 2014 Smart Electric Scooter

Last month, the German automaker Smart, revealed that their all-new electric scooter would be released in 2014. Despite making the release date public, Smart chose not to clue consumers in on any additional details. That is until now. The company, primarily known for manufacturing microcars, has just specified several characteristics of its upcoming escooter, including its price, range, battery type, construction and tech capabilities.

The 2014 Smart Electric Scooter

Smart’s electric scooter will feature a 48-volt lithium-ion battery pack, which supplies power to a 4-kW electric motor. The scooter’s motor is a wheel-hub unit, located at the rear wheel. As for performance, Smart’s scooter will turn out approximately 5.4-horsepower.

Smart has limited the vehicle’s speed range to 28-mph so individuals without a driver’s license can still operate it. In order to power the vehicle users will have to charge the unit’s lithium-ion battery anywhere from three to five hours. A fully charged Smart electric scooter will be capable of traveling up to 60 miles.

Innovative Features

For those interested in body construction, the new escooter consists of a steel and aluminum frame. The scooter’s solid structure also comes equipped with an airbag, ABS, and Blind Spot Assist. Not commonly found on scooters, Blind Spot Assist features are typically present on luxury automobiles. The vehicle’s breaking is controlled by one lever on the handlebar’s right side, which initiates the front hydraulic disc brake.

e-mobility

As is true with other Smart vehicles, the escooter will be part of the Smart e-mobility program. The e-mobility feature allows owners to integrate their escooter with their smartphone. When engaged, users’ phones can serve as a speedometer, range indicator, charge-point finder and navigation system.

The escooter’s impressive list of standard features and unique construction will set consumers back about $5,000, based on early estimates. For sake of comparison, Vespa’s 2012 line of motor scooters costs anywhere from $3,299 for the 2012 Vespa S 50 4V to $6,999 for the upscale 2012 Vespa GTV 300.

Car2Go

According to Smart, its forthcoming scooter will be part of the Car2go program, which presently operates in numerous North American and European cities. A subsidiary of Daimler AG, Car2go is a pioneering program designed to allow drivers to receive all the benefits of owning a car, without the high costs and annoyances. Car2go members can access a number of different vehicles by simply swiping their membership card near the car, then drive away. When they’re finished, drivers just return the car to its designated parking space.

Smart Scooter Coming To The U.S.
Smart initially unveiled the escooter at the Paris Motor Show in September 2010. Smart also showcased its all-new electric bike at the same 2010 motor show. Like the escooter, Smart’s electric bike averages around 60 miles of range per charge. Winner of the prestigious Red Dot Design Award, the ebike is currently only available overseas, but an updated U.S. version is due out “soon,” according to Smart.

Stay tuned for additional escooter details, including a specific release date. Also look for further information regarding the U.S. release of Smart’s ebike.

2014 Smart eScooter concept electric scooter

source : http://www.allaboutbikes.com/motorcycle-news/industry-news/6951-update-on-2014-smart-electric-scooter

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Using Analog Circuit to Manage Power in Low-Power Solar Systems

From large panels to harvested microwatts from a few photodiodes, solar power is increasingly prevalent in autonomously powered systems. With the worldwide evolution toward lower power operation using more “green” energy sources, emphasis on deploying solar power in a greater variety of environments has been on the rise.

In low-power solar systems, it is critical to assess whether there is sufficient sunlight at a given time to power the system. In some cases, this involves determining whether there is sufficient power to enable the microcontroller. In many ultra-low-power systems, the simple act of waking the microcontroller to make a voltage measurement might collapse the solar source or waste precious power from a reservoir capacitor.

One solution is to incorporate a simple analog op amp into the system. An ultra-low-power analog op amp can support “always-on” circuitry around the microcontroller and may be the simplest and best solution.

Ultra-Low-Power Op Amps

Figures 1 to 3 illustrate a few simple circuits using an ultra-low-power op amp in a continuous “always-on” measurement mode assessing the state of the solar cell. The technique hangs on using an op amp whose total power is as low as practical driven primarily by ultra-low supply voltage operation.

The circuit in Fig. 1 shows a photodiode in photovoltaic zero-bias mode. The short-circuit current is measured and converted to a voltage across resistor R1 while the feedback action of the op amp forces 0 V across D1. Zero-bias photovoltaic current is a convenient parameter that is generally well characterized and can be directly referenced to most photodiode manufacturer datasheets. Note that with the rail-to-rail input range of the analog op amp, in this case Touchstone Semiconductor’s TS1001 op amp, the photodiode may be connected directly to the positive supply voltage rail.

Figure 1  An ultra-low-power op amp can be a continuous, “always-on” measurement mode.

The circuit in Fig. 2 generates a simple positive-polarity output for a similar zero-bias-mode measurement. In this case, the op amp servos its output to sink sufficient current to support the zero bias condition for D1. This creates a voltage across resistor R1 at the negative supply voltage pin of the TS1001. Since this ultra-low-power op amp contributes less than 1 μA to this current, the current measured from D1 has minimal error. 

Figure 2  An ultra-low-power op amp offers simple, positive polarity output to support a zero bias condition.

For a more comprehensive assessment, the circuit in Fig. 3 tests the solar source to see if it can handle the load. The circuit shown makes this assessment without burdening the microcontroller and risking collapse of the supply during measurement. 

Figure 3  An ultra-low-power op-amp-based circuit assesses a PV solar-cell source.

Approximately once per 100 ms, the circuit disconnects the solar-cell power source from its reservoir capacitor and load, applying a test load (R1) and assessing the resulting voltage drop. If the voltage drops 25% or more, the result is latched into U2 and the power status is provided to the microcontroller.

This ultra-low power circuit draws less than 3 μA at 1V. Op amp U1 provides the timer function and controls transistor switches T1 and T2 to apply the test load while simultaneously disconnecting the load. Capacitor C1 temporarily holds the voltage to keep this circuitry and any standby loads powered. Op amp U2 serves as a comparator, tripping when the power source drops more than 25% (with 5% hysteresis). Transistor T3 latches the result, while transistor T4 resets the latch during each assessment period to ensure a fresh reading.

Such test loading is useful for determining the available power from a solar cell, since merely measuring the open circuit voltage generally does not provide an accurate assessment.

Assessing “Always-On” Circuitry

Generally, an ultra-low-power op amp, like Touchstone Semiconductor’s TS1001, is an excellent option for supporting “always-on” analog circuitry. For example, op amps that are guaranteed to operate under 1 V and consume less than 1 μA current may be configured as a filter and left continually on, so that a microcontroller making an ADC measurement does not have to stay powered on while the filter settles.

In conclusion, ultra-low-power op amps are useful in low-power solar systems to assess the available power from solar cells before a load is applied, and generally to support standby, “always-on” circuitry, while drawing negligible currents.

source :http://www.eeweb.com/blog/brett_fox/using-analog-components-to-manage-power-in-low-power-solar-systems5

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Mesh/Current Analysis

The technique of nodal analysis described in the preceding topic is completely general and can always be applied to any electrical network. This is not the only method for which a similar claim can be made, however. In general, we shall meet a generalized nodal analysis method and a technique known as loop analysis. Let us first consider a method known as mesh analysis. Mesh Method is perhaps the most popular technique used by engineers to solve complex circuit problems.

Even though this technique is not applicable to every network, it is probably used more often than it should be and it can be applied to most of the networks to be analyzed. Mesh analysis is applicable only to those networks which are planar, a term we hasten to define. The mesh is a property of a planar circuit and is not defined for a non-planar circuit. We define a mesh as a loop which does not contain any other loops within it.

Mesh Currents and Essential Meshes

Mesh analysis works by arbitrarily assigning mesh currents in the essential meshes. We define mesh current as a current which flows only around the perimeter of a mesh. The mesh current may not have a physical meaning but it used to set up the mesh analysis equations. To help prevent errors when writing out the equations, it is important to have all the mesh currents loop in the same direction when assigning the mesh currents. A mesh current is indicated by a curved arrow that almost closes on itself and is drawn inside the essential mesh.

Figure 1  Meshes in a Circuit

 

The convention is to have all the mesh currents looping in a clockwise direction because error-minimizing symmetry then results in the equations. Mesh analysis greatly simplifies the problem by ensuring that the least possible number of equations regarding currents is used. The current through any branch must be determined by considering the mesh currents flowing in every mesh in which that branch appears. That is not difficult because it is obvious that no branch can appear in more than two meshes.
Example:

What is the voltage across the current source?

Figure 2  Example Circuit

Defining the mesh currents in the conventional way, the KVL equation for mesh 1 is:

KVL for mesh 2:

By inspection of mesh 3:

Subsequent elimination of  i3 in the mesh 2 equation leads to:

Adding the two equations immediately above produces:

Back substitution of i1 into one of the equations involving both i1 and i2 produces:

As a straightforward way to find the voltage across the current source is to evaluate the voltage across the 5 Ohm resistor. The current through the resistor is i2 - i3 = 0.78A, thus the voltage across the resistor must be (0.78 A) (5 ohm) = 3.89 V.

Source : http://www.eeweb.com/blog/andrew_carter/mesh-analysis

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Some Useful Techniques of Circuit Analysis

Describing voltage and current relationships in electric circuits are often precisely analogous with the resultant equations when dealing with mathematical behavior of fluid-flow and heat-flow systems, the dynamic response of aircraft control surfaces and other non-electrical phenomena. Rather than building a prototype of the actual physical system, it is much easier and cheaper to construct the analogous electric circuit. As various elements are changed, the electric circuit may then be used to predict the performance of the other system.
One of the primary goals of this tutorial is to learn the methods of simplifying the analysis of more complicated circuits. Among these methods include nodal analysis, mesh, loop and superposition. In order to simplify the analysis, we investigate several different techniques for isolating specific parts of a circuit.

Nodal Analysis

Nodal Analysis is a systematic method for performing circuit analysis. It is also known as the node-voltage analysis or the branch current method which is used to determine the voltage between nodes in an electrical circuit. The basis of nodal analysis is the Kirchoff’s current law which helps determine all of the node voltages in a closed circuit.

Figure 1  A Typical Circuit Node

The procedure for nodal analysis can be divided into three basic steps:

   1. Label the node voltages with respect to a ground
   2. Apply KCL to each of the nodes in terms of the node voltages
   3. Determine the unknown node voltages by solving the simultaneous equations from step 2
Example 1:

Use nodal analysis to fond the voltage at each node of the circuit below.

Figure 2  Example 1

Solution:

The bottom pair of nodes is actually 1 extended node making the number of nodes 3. The number of nodes is counted as shown below.

Figure 3

Node 2 will be assigned a voltage of zero and will be chosen as the reference node. For each node, Kirchoff’s Current Law is written down. The voltage at node 1 is V1 and the voltage at node 3 is V3 while V2 is zero. The following system of equations is the result:

The KCL applied at node 1 is the result of the first equation and the KCL applied at node 3 is the second equation result. By using the inspection method, this form for the system of equations could have been gotten immediately.

Example 2:

To find the voltage at each node of this circuit, use nodal analysis.
Solution:

As shown in the image below, the number of nodes is 4 and the node 4 is assigned a voltage of zero as the reference node.

For each node, the Kirchoff’s Current Law is written down, where V1 is the voltage at node 1, V2 at node 2 and so on. The resulting system of equations:

The nodal analysis does not accommodate a voltage source if you may have noticed. The voltage sources were defined with a small series resistor, representing internal resistance of the source in the early days. A clever method later hatched to include voltage-defined components call Modified Nodaly Analysis.

References
http://www.mathonweb.com/
http://upload.wikimedia.org/

Source : http://www.eeweb.com/blog/andrew_carter

/some-useful-techniques-of-circuit-analysis

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IR Introduces Family of Rugged, Reliable Automotive-Qualified Power MOSFETs Housed in TO-220 Fullpak Package

International Rectifier introduced a family of automotive-qualified power MOSFETs housed in a rugged TO-220 fullpak package for automotive applications including BLDC motors, pumps and cooling systems.

The new 55V planar devices are available as standard and logic level gate drive MOSFETs in N and P channel configuration, and offer a maximum on-state resistance (RDS(ON)) as low as 8mOhm. The TO-220 fullpak package eliminates the need for additional insulating hardware to simplify design and improve overall system reliability.

IR’s automotive MOSFETs are subject to dynamic and static part average testing combined with 100 percent automated wafer level visual inspection as part of IR’s automotive quality initiative targeting zero defects. AEC-Q101 qualification requires that there is no more than a 20 percent change in RDS(ON) after 1,000 temperature cycles of testing. However, in extended testing IR’s new AU bill of materials demonstrated a maximum RDS(ON) shift of less than 10% at 5,000 temperature cycles, showing the strength and ruggedness of the bill of materials.

The new devices are qualified according to AEC-Q101 standards, feature an environmentally friendly, lead-free and RoHS compliant bill of materials.

 Specifications

Standard Gate Drive

Part Number	Package	V(BR)DSS (V)	RDS(ON) MAX. @ 10VGS (mOhm)	ID MAX @ TC = 25°C (A)	QG TYP. @ 10VGS (nC)
AUIRFI3205	TO-220 FullPak	55	8.0	56	113
AUIRFIZ44N	TO-220 FullPak	55	24	28	43
AUIRFIZ34N	TO-220 FullPak	55	40	19	23
AUIRFI4905	TO-220 FullPak	–55	20	–74	120

Logic Level Gate Drive

Part Number	Package	V(BR)DSS (V)	RDS(ON) MAX. @ 4.5VGS (mOhm)	ID MAX @ TC = 25°C (A)	QG TYP. @ 4.5VGS (nC)
AUIRLI2505	TO-220 FullPak	55	8.0	58	130

Availability and Pricing

Pricing ranges from US $0.37 each for the AUIRFIZ34N in 100,000-unit quantities to US $0.78 each in 100,000-unit quantities for the AUIRFI4905. Production orders are available immediately. Prices are subject to change.

Source : irf.com

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