Monday, September 30, 2013

3 Input Video MUX Cable

The circuit diagram shows a low-cost 3-input video MUX cable driver. In this circuit, the amplifier is loaded by the sum of RF and RG of each disabled amplifier. Resistor values have been chosen to keep the total back termination at 75 Ω while maintaining a gain of 1 at the 75-Ω load. The switching time between any two channels is approximately 32 ns when both enable pins are driven. When designing a circuit board for this cable driver, care should be taken to minimize trace lengths at the inverting input. The ground plane should also be pulled away from RF and RG on both sides of the board to minimize stray capacitance. Current consumption of the cable driver is a modest 8mA.

3-Input Video MUX Cable Driverw

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Sunday, September 29, 2013

Two LED Voltage Indicator

There are many applications where the accuracy of a digital or analogue (bar graph) is not required but something better than a simple low/high indicator is desirable. A battery charge level indicator in a car is a good example. This simple circuit requiring only two LEDs (preferably one with a green and red LED in a single package), a cheap CMOS IC type 4093 and a few resistors should ful-fil many such applications. With a suitable sensor, the indicator will display the relevant quantity as a colour ranging from red through orange and yellow to green. IC1.A functions as an oscillator running at about 10 kHz with the component values given, although this is not critical.

Assuming for the moment that R1 is not commented, the output of IC1.A is a square wave with almost 50% duty cycle. The voltage at the junction of R2 and C1 will be a triangular wave (again, almost) with a level determined by the difference in the two threshold voltages of the NAND Schmitt trigger gate IC1.A. IC1.B, IC1.C and IC1.D form inverting and noninverting buffers so that the outputs of IC1.C and IC1.D switch in complementary fashion. With a 50% duty cycle, the red and green LEDs will be driven on for equal periods of time so that both will light at approximately equal brightness resulting in an orange-yellow display. With R1 in circuit, the actual input voltage to IC1.

A will consist of the triangular waveform added to the dc input Vin. As the input voltage varies, so will the oscillator duty cycle causing either the red or the green LED to be on for longer periods and so changing the visible color of the combi-LED. The actual range over which the effect will be achieved is determined by the relative values of R1 and R2, enabling the circuit to be matched to most supply voltages. With the component values given and a supply of 8 volts, the LED will vary from fully red to fully green in response to input voltages of 2.5 V and 5.6 V respectively. To monitor a car battery voltage, the battery itself could be used to power the circuit provided a zener diode and dropper resistor are added to stabilize the IC supply voltage.

This is shown in dashed outlines in the circuit diagram. With an 8.2 V zener the dropper resistor should be around 220 ? and R1 has to be reduced to 4.7 k. The LED brightness is determined by R4. As a rule of thumb, R4 = (Vsupply – 2) / 3[k] and remember that the 4093 can only supply a few mA’s of output current. Applications of this little circuit include ‘non critical’ ones such as go/non-go battery testers, simple temperature indicators, water tank level indicators, etc.
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Saturday, September 28, 2013

Courtesy Light Extender

In essence, this circuit is a 15 to 20-second courtesy light extender for cars. It is activated in the usual way by opening a door but it also samples the negative lock/unlock signals from a car alarm or central locking and does two more things. First, when an unlock signal is received, it turns on the courtesy light for 15-20 seconds before you open the door. Second, when a lock signal is received, it turns off the courtesy light immediately, with no fade-out. This is done to eliminate false triggering of the burglar alarm through current drain sensing. When a car door is open or the unlock relay is activated, the 33µF capacitor discharges through diode D1 and this keeps transistor Q1 turned off.

Courtesy light extender circuit schematic

This allows Q2 and Q3 to turn on and the courtesy lamp is activated. When the door is closed, the courtesy lamps stay illuminated and the 33µF electrolytic capacitor starts charging through the associated 1MO resistor. As the voltages rises, Q1 turns on slowly, turning off Q2 and Q3 which gradually fades out the courtesy lamp. If a lock signal from the central locking system is received, relay 1 closes and charges the capacitor instantly, so the lamp turns off immediately. Relays were used to interface to the central locking/alarm system as a safety feature, to provide isolation in case something goes wrong.
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Friday, September 27, 2013

Long Delay Timer Circuit

Suitable for battery-operated devices, Fixed 35 minutes delay

This timer was designed mainly to switch off a portable radio after some time: in this way, one can fall asleep on the sand or on a hammock, resting assured that the receiver will switch off automatically after some time, saving battery costs.

Circuit operation:

R1 and C1 provide a very long time constant. When P2 is momentarily closed, C1 discharges and the near zero voltage at its positive lead is applied to the high impedance inputs of the four gates of IC1 wired in parallel. The four paralleled gate outputs of the IC go therefore to the high state and the battery voltage is available at Q1 Emitter. When P2 is released, C1 starts charging slowly through R1 and when the voltage at its positive lead has reached about half the battery voltage, the IC gate outputs fall to zero, stopping Q1.

This transistor can directly drive a portable radio receiver or different devices drawing a current up to about 250mA. Connecting a Relay across the Emitter of Q1 and negative ground, devices requiring much higher voltage and current operation can be driven through its contacts. Pushing on P2 for 1 to 5 seconds, the circuit starts and then will switch off after about 35 minutes. This time delay can be varied by changing R1 and/or C1 values. P1 will stop the timer if required.
LED D1 is optional and can be useful to signal relay operation when the load is placed far from the timer.

Circuit diagram:

Long Delay Timer Circuit

Long Delay Timer Circuit Diagram

Parts:

R1_________10M 1/4W Resistor
R2_________4K7 1/4W Resistor
R3_________1K 1/4W Resistor (Optional, see Text)
C1_________220µF 25V Electrolytic capacitor
D1_________LED any type and color (Optional, see Text)
D2_________1N4148 75V 150mA Diode (Optional, see Text)
IC1_________4011 Quad 2 Input NAND Gate CMos IC (See Notes)
Q1_________BC337 45V 800mA NPN Transistor
P1,P2______SPST Pushbuttons
RL1________Relay with SPDT 2A @ 230V switch (Optional, see Text)
Coil Voltage 12V - Coil resistance 200-300 Ohm
Notes:

  • A 4011 Quad 2 Input NAND Gate was used for IC1, but many other CMos gates or inverter arrays can be used in its place, e.g. 4001, 4002, 4025, 4012, 4023, 4049, 4069. With these devices, all inputs must be tied together and also all outputs, as shown in the Circuit diagram.
  • The operating voltage of this circuit should lie in the 6 - 12V range.

Source: www.RedCircuits.com

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Thursday, September 26, 2013

2012 Hyundai Genesis Owners Manual

here 2012 Hyundai Genesis Owners Manual
maybe you will need this owner manual so we provides post about this vehicle. beware before you download please to make sure you know this pdf is not on our hosted.
readour privacy first before you download this  2012 Hyundai Genesis Owners Manual
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Wednesday, September 25, 2013

Battery powered Night Lamp Circuit

Ultra-low current drawing 1.5V battery supply

This circuit is usable as a Night Lamp when a wall mains socket is not available to plug-in an ever running small neon lamp device. In order to ensure minimum battery consumption, one 1.5V cell is used, and a simple voltage doubler drives a pulsating ultra-bright LED: current drawing is less than 500µA.
An optional Photo resistor will switch-off the circuit in daylight or when room lamps illuminate, allowing further current economy.
This device will run for about 3 months continuously on an ordinary AA sized cell or for around 6 months on an alkaline type cell but, adding the Photo resistor circuitry, running time will be doubled or, very likely, triplicated.

Circuit diagram :

Battery-powered Night Lamp Circuit diagram Battery-powered Night Lamp Circuit diagram

Parts:

R1,R2___________1M   1/4W Resistors
R3_____________47K 1/4W Resistor (optional: see Notes)
R4____________Photo resistor (any type, optional: see Notes)

C1____________100nF 63V Polyester Capacitor
C2____________220µF 25V Electrolytic Capacitor

D1______________LED Red 10mm. Ultra-bright (see Notes)
D2___________1N5819 40V 1A Schottky-barrier Diode (see Notes)

IC1____________7555 or TS555CN CMos Timer IC

B1_____________1.5V Battery (AA or AAA cell etc.)


Circuit operation:



IC1 generates a square wave at about 4Hz frequency. C2 & D2 form a voltage doubler, necessary to raise the battery voltage to a peak value able to drive the LED.



Notes:


  • IC1 must be a CMos type: only these devices can safely operate at 1.5V supply or less.

  • If you are not needing Photo resistor operation, omit R3 & R4 and connect pin 4 of IC1 to positive supply.

  • Ordinary LEDs can be used, but light intensity will be poor.

  • An ordinary 1N4148 type diode can be used instead of the 1N5819 Schottky-barrier type diode, but LED intensity will be reduced due to the higher voltage drop.

  • Any Schottky-barrier type diode can be used in place of the 1N5819, e.g. the BAT46, rated @ 100V 150mA.


Source : www.redcircuits.com

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Tuesday, September 24, 2013

Processor Fan Control Circuit

Fans in PCs can be objectionably loud. In many cases, the amount of noise produced by the fan can be considerably reduced by lowering its speed. Although this will decrease the amount of cooling, this need not be a problem as long as you don’t go overboard with slowing down the fan. Particularly with older-model processors, which consume quite a bit less power than the latest models, this trick can be used without any problems. This circuit is anyhow intended to be used with relatively old PCs, since more recent models generally have a fan control circuit already integrated into the motherboard. These controllers ensure that the amount of cooling is increased if the processor becomes too warm and decreased if the processor temperature is relatively low.

Circuit diagram:

Processor_Fan_Control_Circuit_Diagramw

Processor Fan Control Circuit Diagram:

The circuit described here consists of only a handful of components, which you will probably already have in a drawer some-where. Transistors T1 and T2 are driven into conduction by the base current flowing to the fan via P1 and D1. There will always be a current flowing through R1, and it will be approximately 120 times as large as the current through R2. R3 has been added to prevent the base current of T2 from becoming too large when P2 is set to its minimum resistance. D1 ensures that even at this extreme setting, the voltage on the base-emitter junction of T3 will still be large enough to allow it to conduct.

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Monday, September 23, 2013

Comparator Based Crystal Oscillator

Although a simple crystal oscillator may be built from one comparator of an LT1720/LT1721, this will suffer from a number of inherent shortcomings and design problems. Although the LT1720/LT1721 will give the correct logic output when one input is outside the common mode range, additional delays may occur when it is so operated, opening the possibility of spurious operating modes. Therefore, the DC bias voltages at the inputs have to be set near the center of the LT1720/LT1721’s common mode range and a resistor is required to attenuate the feedback to the non-inverting input. Unfortunately, although the output duty cycle for this circuit is roughly 50%, it is affected by resistor tolerances and, to a lesser extent, by comparator offsets and timings.
Comparator Based Crystal Oscillator
If a 50% duty cycle is required, the circuit shown here creates a pair of complementary outputs with a forced 50% duty cycle. Crystals are narrow-band elements, so the feedback to the non-inverting input is a filtered analogue version of the square-wave output. The crystal’s path provides resonant positive feedback and stable oscillation occurs. Changing the non-inverting reference level can vary the duty cycle. The 2k-680Ω resistor pair sets a bias point at the comparator + (Comparator IC1a) and – (Comparator IC1b) input. At the complementary input of each comparator, the 2k-1.8k-0.1µF path sets up an appropriate DC average level based on the output.
IC1b creates a complementary output to IC1a by comparing the same two nodes with the opposite input. IC2 compares band-limited versions of the outputs and biases IC1a’s negative input. IC1a’s only degree of freedom to respond is variation of pulse width; hence the outputs are forced to 50% duty cycle. The circuit operates from 2.7V to 6V. When ‘scoping the oscillator output signal, a slight dependence on comparator loading, will be noted, so equal and resistive loading should be used in critical applications. The circuit works well because of the two matched delays and rail-to-rail outputs of the LT1720.
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Sunday, September 22, 2013

Portable 9v Headphone Amplifier

High Quality One-IC unit, Low current consumption
After several requests by correspondents, the decision of designing a 9V powered Headphone Amplifier was finally taken. The main requirement was to power the circuit by means of a common, PP3 (transistor radio) alkaline battery. So, implementing a low current drawing circuit was absolutely necessary, though preserving a High Quality performance.

Circuit Diagram:
Portable 9v Headphone Amplifier Circuit Diagram
Parts:
P1 = 22K
R1 = 18K
R2 = 68K
R3 = 68K
R4 = 68K
R5 = 18K
R6 = 68K
C1 = 4.7uF-25v
C2 = 4.7uF-25v
C3 = 22pF
C4 = 220uF-25v
C5 = 220uF-25v
C6 = 4.7uF-25v
C7 = 22pF
C8 = 220uF-25v
J1 = 3.5mm Stereo Jack
B1 = 9V Alkaline Battery
IC1 = NE5532-34
SW1 = SPST Toggle Switch

The appearance of the 5534 low-noise op-amp at a reasonable price was much appreciated by audio designers. It is now difficult or impossible to design a discrete stage that has the performance of the 5534 without quite unacceptable complexity. 5534 op-amps are now available from several sources, in a conventional 8-pin d.i.l. format. This version is internally compensated for gains of three or more, but requires a small external capacitor (5-15pF) for unity-gain stability. The 5532 is a very convenient package of two 5534s in one 8-pin device with internal unity-gain compensation, as there are no spare pins.

The 5534/2 is a low-distortion, low-noise device, having also the ability to drive low-impedance loads to a full voltage swing while maintaining low distortion. Furthermore, it is fully output short-circuit proof. Therefore, this circuit was implemented with a single 5532 chip forming a pair of stereo, inverting amplifiers, having an ac gain of about 3.5 and capable of delivering up to 3.6V peak-to-peak into a 32 Ohm load (corresponding to 50mW RMS) at less than 0.025% total harmonic distortion (1kHz & 10kHz). If we consider that the mean current drawing at a power output of 15mW per channel is around 12-13mA (both channels driven), this Headphone Amplifier will become a must for many DIY enthusiasts needing a High Quality, High Performance portable device.

Technical data
Sensitivity:
    200mV RMS for 15.6mW RMS output
    350mV RMS for 50mW RMS output
Maximum undistorted output: 3.6V Peak-to-peak
Frequency response: flat from 40Hz to 20KHz; -2.3dB @ 20Hz
Total harmonic distortion @ 1KHz: <0.025% at all power outputs up to 50mW RMS
Total harmonic distortion @10KHz: <0.02% at all power outputs up to 50mW RMS
Total current drawing @ 9V supply (both channels driven):
    Standing current: 8.5mA
    Mean current drawing @ 15mW RMS per channel: 12mA
    Mean current drawing @ 35mW RMS per channel: 17mA
 Source : www.redcircuits.com
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Saturday, September 21, 2013

Fuse Box BMW 325i 1992 Convertible Power Distribution Diagram

Fuse Box BMW 325i 1992 Convertible Power Distribution Diagram - Here are new post for Fuse Box BMW 325i 1992 Convertible Power Distribution Diagram.

Fuse Box BMW 325i 1992 Convertible Power Distribution Diagram



Fuse Box BMW 325i 1992 Convertible Power Distribution Diagram
Fuse Box BMW 325i 1992 Convertible Power Distribution Diagram

Fuse Panel Layout Diagram Parts: Service Interval Indicator, Tachometer/Fuel Economy Gauges, Gauges/Indicators;, Brake Warning System, Back Up Lights, On Board Computer, Start, Injection Electronics, Active Check Contro, Cruise Control, Injection Electronics, Radio/Antenna, Speedometer/Indicators, On Board Compute, Front Park/Tail, Horn, Rear Defogge, Injection Electronics, Ignition Key Warning/Seatbelt Warning, Auxiliary Fan, Auto Chraging Flashlight, Ignition Key Warning/Seatbelt WarninActive Check Control, Lights, Interior Lights , Central Locking, Radio/Antenna, On Board Computer, Cigar Lighter, Radio/Antenna, Heated/Air Conditioning, Active Check Control, Front Side Marker, Headlights, High Beam Indicator, Headlight, Auxiliary Fan, Lights, Turn/Hazard Warning, Wiper/Washer, Stop Lights, Active Check Control, Antilock Braking System;, Cruise Control, Map Reading Light, Headlights, Heated Seats, Power Windows, Auxiliary Fan, Auxiliary Fan, Interior Light, Power Mirrors, Injection Electronics, Interior Lights, Radio/Antenna, Trunk Light, Active Check Control, Service Interval Indicator, On Board Computer, Tachometer/Fuel Economy Gauge, Electro Mechanical Convertible Top.
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Friday, September 20, 2013

1995 Ford Ranger Wiring Diagram

1995 Ford Ranger Wiring Diagram

The Part of 1995 Ford Ranger Wiring Diagram: transmission range sensor, electronic engine control, clutch pedal position switch jumper, electronic engine control, speed control, automatic transmission, starter interupt relay, rela box, starter motor during engine starting, starter relay, manual transmission, electronic engine control, battery, starter motor solenoid, switch jumper, I/P fuse panel.
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Thursday, September 12, 2013

Testing A FT245RL Chip with Software

Chips FT245RL testing, checking for the program. It can set the output and input signals to the findings and submit. It is thus possible to enable or disable the 8 channels, for a 8-channel input. It all started a long time ago. Once, when I learned that the computer can be sent off signals that you can manage yourself, immediately began to take interest in the way they can do. It was somewhere in ~ 2002. After browsing the internet and found some examples of how the device can be connected to an LPT Port,.

Testing A FT245RL Chip with Software

Since that time almost all computers have an LPT port, its all gone well. In the LPT port connected LEDs managed a program written by someone that has been written as to support in the MS-DOS. It certainly was not a pleasant appearance, ease of operation ... Was only possible to manage such a procedure, a combination of ... as was intended by its creator. Therefore, once thought myself why can not I create and manage the program as he wants. So began an interest in computer programming and bonding with their devices.
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Wednesday, September 11, 2013

KLR250 Chain Adjustment

One of the most important items that need to be maintained the KLR250, or any motorcycle for that matter, is the drive chain. Failure to clean, lubricate, and adjust the chain at regular intervals can result in premature wear of the chain and sprockets. A worn or misadjusted drive chain can break or slip off the sprockets causing the rear wheel to lock up sending the bike out of control. In this article were going to look at the basics of adjusting the chain of your KLR250.

Kawasaki KLR250 Chain AdjustmentTo the left is a diagram that shows the chain and sprockets. The part in the middle is the swingarm, which is what the rear wheel is attached to. On the front part of the swingarm there is a plastic chain guard that is held on with one bolt. That bolt is where youll check for slack in the chain which will tell you whether it is adjusted properly or not.

Items Needed:

-Ft/lb torque wrench
-New cotter pin
-Basic hand tools

According to the Kawasaki KLR250 owners manual the correct way to check for proper chain slack begins with placing the bike on its side stand without a driver/passenger on the bike. Because the chain can wear unevenly you should try rotating the rear wheel (WARNING: Watch your fingers by the chain!) until you come to the part where the chain slack is tightest. Then to check for proper slack locate the swingarm guard bolt and directly under it pull the chain up toward the swingarm. The space between the chain and the swingarm should be between 0-5mm or 0-0.2" Check the diagram above for more clarity.

Kawasaki KLR 250 Chain Adjustment AdjustersIf the chain is adjusted properly then youre all set, though dont forget to clean and lubricate the chain. If not then its time to make some adjustments. Adjusting the chain is a fairly straight forward process. The rear wheel is held to the swingarm by a long axle with a large nut at the end. That nut is secured in place with a cotter pin. Using a pair of pliers remove the cotter pin and loosen the nut until you can just barely move the adjusters on the axle. (see picture) If you take a close look at the adjusters youll see that they have numbers on them. The higher numbers represent a tighter chain, lower numbers represent a looser chain. All you have to do is turn those adjusters until you see that the chain adjustment is correct, being sure that the adjusters on both sides are on the same number in relation to the metal pin they press against. Failure to make sure both adjusters are in the same position will result in the chain derailing.

Once youve gotten the chain adjusted correctly all that is left to finish up this project is to tighten the axle nut to 69 ft/lbs with a torque wrench and insert a new cotter pin. Before installing the new cotter pin its best to check the chain slack one last time and youre good to go! FYI: Kawasaki recommends checking chain slack every 600 miles.

Note: Eagle eye visitors have pointed out that my adjusters are on upside down. This is the way they were when I purchased the bike. When checking my rear bearings I decided to change them back to the stock setup and found that it was much harder to keep the adjusters in place while tightening the axle nut so I changed them back to this configuration. I can only assume that is why the previous owner set them this way. It works for me so...
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Tuesday, September 10, 2013

12V to 220V 100W Transistor Inverter Circuit Diagram

 12V to 220V 100W Transistor Inverter Circuit Diagram

12V to 220V 100W Transistor Inverter

12V to 220V 100W transistor based power inverter.
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Wednesday, September 4, 2013

Radio Controlled Motor Using AF2310

This circuit is very similar with a car radio controlled toy with seven control functions: forward, forward-left, forward-right, backward, backward-left, backward-right, and stop. Also you can use this radio frequency circuit for some other electronic circuits that require a simple wire less motor controller. The remote control work’s at a frequency of 27.9 MHz and require a 9 volts power supply .This RF motor controller circuit consist from two parts a Radio Transmitter and a Radio Receiver .

Both circuits receiver and transmitter are based on the AF2310 integrated circuit .For remote control contacts you can use some push buttons or a mini-joystick .Commands are controlled by different sets of electrical contacts that are used to encode a sequence of electrical pulses; the number of pulses depends on which command is being sent.

An electrical circuit that is tuned to a frequency of 27.9 MHz creates a signal that is sent to the antenna when the pulses are active. The antenna converts the electrical energy into radio energy, creating a stream of radio energy bursts, which travel through the air and are picked up by and understood by the radio receiver in the car. The car antenna collects radio energy and transform it back into electrical energy.If the car is turned on then the radio receiver in the car is continuously monitoring the electrical energy from its antenna.



The receiver is a filter which is tuned to amplify any energy around 27.9 MHz and block energy the antenna picks up outside this region. If the Remote Control Transmitter is sending commands then its radio signal will be picked up by the receiver and converted back into the original pulse sequence. Decoding circuitry then determines which commands were sent by measuring the number of received pulses in the sequence. Signals are then sent to the motors to execute the commands.





When operated with strong batteries and in an open area the range will be at least 40 ft. Obstacles will degrade the radio signal’s ability to travel through air and reduce operating range, but will never block it completely. In the car, weak batteries will reduce power to the Motor and degrade the receiver’s ability to filter, amplify, and decode commands from the Transmitter.

When a command is received to turn left or right, a voltage is applied to the Steering Motor Since the Front Wheels are connected to the Steering Bar, the car will turn. To the turn the other direction, the voltage to the motor is reversed.The Driving Motor works the same as the Steering Motor. When a command is received to go forwards a voltage is applied to the Driving Motor; this voltage is reversed to go backwards.
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Tuesday, September 3, 2013

Stereo Balance Indicator

This stereo balance indicator circuit diagram is designed using few common external components .The schematic circuit is very simple to build and will provide an visual indication with LEDs for left , right and center balance . 

Stereo Balance Indicator Circuit Diagram

 Stereo Balance Indicator Circuit Diagram

Outputs from each channel are fed to the two inputs of IC1 connected as a differential amplifier . Output of the IC1 is connected to the noninverting inputs of the IC2 and IC3 . If the outputs of the IC1 approaches the supply rail , the outputs of the IC2 and IC3 will go high illuminating the LED 3 , this will show that the right channel is dominating . If the sound is balanced to the left channel , the Ic2 and IC3 will go low and the LED1 will light . If both channels are equal in amplitude the outputs of the IC2 and IC3 would be low and high respectively , lighting up LED2 .


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Monday, September 2, 2013

Digital Clock Using with PIC16C54

Digital clock project based on the PIC16C54 microcontroller can be designed using the following circuit diagram . This digital clock electronic project based on the PIC16C54 is a simple time-of-day clock incorporating four seven-segment LED displays and three input switches. There is also an additional reset switch that would not normally be incorporated into the final design.

Digital clock Circuit diagram 



The common cathode for each display is turned on with transistors connected to the four I/O lines of PORTA . A low output turns on the PNP transistor for the selected display. The PORTB pins activate the LED segments.

The PORTB pins activate the LED segments. The switches are also connected to PORTB I/O pins.
When no buttons are pressed, the circuit will display the current time, starting at 12:00 on reset.
Pressing SW1 will cause seconds to be displayed. The time is set by pressing SW2 to advance minutes, and SW3 to advance hours . The displays used were common cathode and turned on with transistors to avoid trying to sink too much current into the PIC16C5X. 100 W resistors were used in series with the segments to obtain the desired brightness. Different values may be required if different displays are used.

All of the same display segments are linked together (A-A-A-A, B-B-B-B, etc.) and are individually selected by turning on only the desired display.
This simple digital clock project based on the PIC16C54 microcontroller must be powered from a simple 5 volt DC power supply circuit .
This digital clock project based on the PIC16C54 microcontroller ( circuit and software ) was designed by Dan Matthews Microchip Technology Inc . Download Source Code
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Sunday, September 1, 2013

PBL3717A Motor Stepper Driver

This motor stepper driver electronic project is designed using the PBL3717 motor driver manufactured by ST Microelectronics . The PBL3717A motor stepper driveris a monolithic IC which controls and drives one phase of a bipolar stepper motor with chopper control of the phase current. Current levels may be selected in three steps by means of two logic inputs which select one of three current comparators.

PBL3717A Motor Stepper Driver Circuit Diagram



When both of these inputs are high the device is disabled. A separate logic input controls the direction of current flow. A monostable, programmed by an external RC network, sets the current decay time. The output current for this project is up to 1A from 10 up to 46 volt motor supply . The logic inputs I0 and I1 set at three different levels the amplitude of the current flowing in the motor winding .

A high level on the "PHASE" logic input sets the direction of that current from output A to output B and a low level from output B to output A. It is recommended that unused inputs are tied to pin 6 (Vss) or pin 4 (GND) as appropriate to avoid noise problem. The current levels can be varied continuously by changing the reference voltage on pin 11.  In this bipolar stepper motor driver project , the Vss is the logic power and must be around 5 volt and VS is the motor power and must be between 10 and 46 volts .
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