RJ45 Port Pinout Circuit

 

RJ45 connector is used for connecting Ethernet port on computer and in Internet system. There are two configuration: straight and cross. This is the figure of the RJ45 connector;

LT1016 – LS74121 Voltage Controlled Pulse Width Generator/ Monostable Multivibrator

Here’s the Mono-stable multivibrator circuit generates a fixed pulse width when receiving a trigger signal on its input. The pulse width of the output is fixed regardless of the input pulse duration/width. In practical application, the width of the output pulse is determined by choosing the right components values for certain application. In today’s digital electronics, mono-stable function can be easily implemented using micro controller. In many practical they’re more than enough, but many experimental works sometime need very specific function with high speed performance while maintaining its flexibility. This is the figure of the circuit diagram.

Guitar And Bass Sustain Circuit

If you are guitar player or want to have wonderful sound of a guitar, where the note just hangs there seemingly forever, you need a sustain booster for your guitar audio outputs. Sustain can be obtained by turning the amp up full, but the rest of the band will just kill you - they need to be able to hear themselves too! This little project is best used in the effects loop of a guitar amp (if it has one - not all do).  It can be used direct from the guitar, but the effect is not as good, since it is designed for relatively high levels (around 1 Volt). Here is a design for guitar and bass sustain schematic diagram. This is the figure of the circuit.

Parameters of Nonlinear Delayed Circuit

This is a design schematic circuit diagram for parameters of nonlinear delayed circuit. This circuit is based on LM 324 as brain of the controller. The nonlinearity is built up of the transistor T 1 , the adjustable amplifier OA 1 and the resistors R 2-R 7. Electronic components: delay line: bucket brigade line MN 3011 with 3328 stages, triggered by MN 3101 (both National Panasonic); OA 1 :LM 324N; C = 660 pF; R 1 = 470 k,R 2 = 100 k lin., R 3 = 22 k, R 4 = 4.7k,R 5 = 10 k,R 6 = 1k,R 7 = 47 k;T 1 BC 238C. This the figure of the circuit schematic.

Car Audio Power Bridging Terms

Not only getting married is there a condition, bridging also has conditions. Because if you do not comply with these conditions then your power can be broken down in just a few hours or just a few songs with no maximum. Then what are the conditions? These conditions have been written by the manufacturer, so you should read the manual that indicates the condition if the power is in the cartridge. 

Then what are the conditions? These conditions have been written by the manufacturer, so you should read the manual that indicates the condition if the power is in the cartridge. In refilling the car audio power, we should not arbitrarily connect the cable, it must be right between the pluses and minuses - that's the first condition.

Single Pushbutton Run-Stop Circuit

If you have a problem for mechanical(push on/push off switch), electromagnetic(latching relay) and electronic(CMOS logic), this circuit is one of the solution circuit but few(if any) good discrete electronic solutions. Here’s the figure of the circuit;

When the pushbutton is initially closed, it directly turns on the gate of Q1 via D2. Q1 turns on after a brief delay determined by the charge time of C1. Q1 then biases Q2 on, and Q2 seals in the pushbutton signal and C2 charges up to 12V via R8 and D2. When the pushbutton is closed again, the top side of C2 is grounded via the pushbutton action through D1. The lower side of C2 goes negative and dumps half of its charge into C3. The negative voltage on C3 turns on Q3 that is connected in the common collector configuration (emitter follower). The emitter of Q3 shorts the bias voltage of Q2 to common thus turning off Q1 (as soon as the pushbutton is released).

Design of Electrical Isolation For I2C Bus Circuit

This is a design circuit for electrical isolation that based control by opto isolator. When the SDA (Serial DAta) lines on both the left and right lines are 1, the circuit is quiescent and optoisolators IC1 and IC2 are not actuated. When the SDA line at the left becomes 0, current flows through the LED in IC1 via R2. The SDA line at the right is then pulled low via D2 and IC1. This is the figure of the circuit;

In this operation of the circuit, opto isolator IC2 does not transfer this 0 to the left, because the polarity of the LED in IC2 is the wrong way around for this level. This arrangement prevents the circuit holding itself in the 0 state for ever. As is seen, the circuit is symmetrical. So, when the SDA line at the right is 0, this is transferred to the left. The lower part of the diagram, intended for the SCL (Serial CLock) line, is identical to the upper part. Resistors R1, R4, R5, and R8, are the usual 3.3 kΩ pull-up resistors that are obligatory in each I2C line. If these resistors are already present elsewhere in the system, they may be omitted here. The current drawn by the circuit is slightly larger than usual since the pull-up resistors are shunted by the LEDs in the optoisolators and their series resistors. Nevertheless, it remains within the norms laid down in the I2C specification.

Photo Switch Circuit using 555 IC

Here’s a design circuit for simple photo switch suitable for home and industrial purpose. The circuit switches on a relay when the light intensity falling on the sensor crosses the set limit. The circuit is based on a NE 555 and two transistors for driving the relay. The resistor R1 is adjusted such a way that under normal condition the voltage across the LDR is less than 1/3 the supply voltage. In this condition output of IC is high.

This makes transistor Q1 on. Transistor Q2′s base is connected to collector of Q1. So Q2 will be off keeping the relay de energized. When light falls the voltage across LDR rises above 2/3 Vcc. This makes the output of IC go high making the relay to energized. The result we get a relay that operates according to the intensity of light falling on the LDR. To setup the circuit switch on power supply, connect a multi meter across LDR and adjust R1 so that voltage across   LDR is just below 1/3 supply voltage. Ensure that relay is off in this condition. If not reduce voltage across LDR further more by adjusting R1 to make relay off.

Now cover the top of LDR using a black paper and see the relay gets activated. If not, make further adjustments with R1.Nothing to care after some trial and error you will get the correct set point of R1 where the circuit works. This circuit  is nothing great, but some simple basics. I have tested this and got good results. So no problem .Just proceed. If there is some chattering in the relay , that may be because off the difference between the turning on and turning off voltages. This can be avoided by connecting a resistor whose value is equal to 1/2 the resistance of LDR at illuminated condition.

Frequency/Tone Decoder Circuit Using TC9400 FVC

Another application of FVC (frequency-to-voltage converter) is tone/frequency decoder. This circuit is used to determine the frequency band of an oscillation signal. This circuit is used in many application like determines the frequency band in the signal and remote control where the frequency band corresponds to a different command. This circuit uses TC9400 F/V converter to convert the frequency to voltage because the frequency must be converted to proportional analog voltage before can be detected. This is the figure of the circuit;

Beside TC9400 F/V converter, this circuit also uses the quad comparators. It used to detect when the frequency limits is exceeded by the voltage (frequency). The frequency is indicated by the logical “1″ at any of the five output. [Circuit diagram source: Microchip Application Note]

Square Root Mode for AD532 Analog Processor

Here’s a design circuit for about the connections for square root mode for ADS532 analog processor chip.  Similar to the division mode, the multiplier cell is connected in the feedback of the op amp by connecting the output back to both the X and Y inputs. This is the figure of the circuit;

To prevent latch up as Zi approaches 0 Volts, the diode D1 is connected. The Vov adjustment is made with Zin = +0.1 V dc in this case, adjusting Vos to obtain -1.0 V dc in the output, Vout =-√(10 VZ). Gain (S.F) and offset (Xo) adjustments are recommended for optimum performance.

2 Phase and 3 Phase Motor Drivers Circuit

Here’s a design circuit for 2-phase and 3-phase motor driver circuits. This circuit can used to drive an AC motor because this circuit has an integrated power operational amplifier, built-in power-output stage and high amplification factor. The needed AC signal is produced by the op amp that is configured as oscillator. The motor is driven by the high-current that is supplied from the power output stage. The another op amp is configured as Wien bridge oscillator. This is the figure of the circuit;

The oscillation frequency is determined by following equation:

f0=1/(2π*squareroot(R1*R2*C1*C2))

The upper schematic diagram is the 2-phase motor driver, while the lower schematic is the diagram of 3-phase motor driver circuit. The oscillator frequency can be adjusted to a narrow range by varying R2 or R1. The signal attenuation  which occurs in the phase shifters is compensated by the second amplifier’s gain. The second amplifier’s gain is set by R3/R4 ratio. The output of this circuit is sinusoidal because of RC feedback networks that used as an active filters. An external source like square wave or pulse can be used to drive this circuit. [Circuit's diagram source: seekic.com]

Enabling 3 Phase Motor to Operates Using Single Phase Supply

Capacitor have been use for decades to operate 3-phase motors on single-phase power. Two single-phase wires are connected to two of the inputs on a 3 phase motor on this method. Then, the capacitors is connected to one of the single -phase inputs and the third leg of the motor. This is the figure of the circuit;

The voltage is allowed to be displaced in time from its parent voltage by phase shift through the capacitor. Voltage distinct from the 2 single-phase lines is the result. The motor will operate if the capacitors value-it’s ability to process electrical current- is sufficient. 6 times as much current to start as it does to run is required by the motor so a static-capacitor phase converter must have some means of switching a large group of capacitors in and out during motor starting. Below is a typical unit uses a potential-type motor starting relay (pirated from a single-phase motor) to regulate the larger start capacitor, while a smaller (in value) capacitor provides continuous power to run the motor. The potential relay removes the start capacitor from the circuit as the motor speed increase, and the motor operates. [Circuit diagram source: gwm4-3phase.com]

Signal Conditioning Circuit for KMI 15/x Rotation Speed Sensor

This is a design circuit for modulated current that is provided by the integrated rotational speed sensor KMI 15/x. This current signal must be converted to ground referenced voltage signal, matching the logic levels of the processing unit for digital signal processing. This signal conditioning can be done by using this circuit. This circuit is consists of protective elements to suppress line conducted interference and low pass filter in front of the comparator input. This is the figure of the circuit;

This circuit uses first-order RC low pass filter as signal filter. This circuit is made of C4 and R3 with cut off frequency of 10 kHz. This cut off frequency is used to achieve an optimum absorption of noise.

Signal Conditioning Circuit for KMI 15/x Rotation Speed Sensor

This is a design circuit for modulated current that is provided by the integrated rotational speed sensor KMI 15/x. This current signal must be converted to ground referenced voltage signal, matching the logic levels of the processing unit for digital signal processing. This signal conditioning can be done by using this circuit. This circuit is consists of protective elements to suppress line conducted interference and low pass filter in front of the comparator input. This is the figure of the circuit;

This circuit uses first-order RC low pass filter as signal filter. This circuit is made of C4 and R3 with cut off frequency of 10 kHz. This cut off frequency is used to achieve an optimum absorption of noise.
 

To block negative interference pulses and protect the sensor and electronics against reverse polarity of the supply voltage, this circuit uses the series diode D1. The suppressor diode D2 is used to limit positive interference pulses. Fast negative and positive interference pulses are absorbed by the capacitor C2. To supply the sensor during short supply voltage breakdown because of negative pulses, the electrolytic capacitor C3 stores energy. [Circuit diagram source: Philips Semiconductors Application Note]

Air Ionizer Circuit

When in atmosphere exists accumulation of negative ions, it has been proved medical, that the human organism reacts favorably. Opposite happens when exists accumulation of positive ions. The lack of negative ions is the main cause for a lot of pathological abnormalities in our organism. Also it can '' clean '' the atmosphere of room from the tobacco of cigarette and the industrial pollution, as dust and exhaust etc, one and the negative ions overlay above in positive the pollutants and the '' neutralizes ''. This is the figure of the circuit; 

It has been observed in periods of powerful storms, when '' they fall '' a lot of lightning, in atmosphere it exists the same sense, one and exists production of negative ions, in enormous quantities. The production of negative ions for us him it makes the above circuit, that is not nothing other than a multiplier of voltage. Thus 230V AC are changed in DC and they are multiplied in + 6500V roughly and via means of R13, they lead in contacts A-b-c-d-e, that is steel spikes (needles of length roughly 3-5cm). The high voltage that exists in the end of spikes, creates continuous flow of negative ions, the phenomenon that it creates and a very lightly blue radiation in their end. Even if the voltage, is high it does not create problem of electrocution (because is small current), but GOOD THEY IS WE DO NOT LEAN IN NO POINT of CIRCUIT, LONG AS THAT WORKS, BUT EVEN LITTLE TIME INTERVAL THAT THIS IS EXCEPT OPERATION, BECAUSE LIKELY THEY IS CHARGE STILL the CAPACITORS. If the circuit is manufactured and try then it will be supposed insulate are well, opened five holes in his side and from there behind are placed the spikes, WITHOUT UNDERHUNG FROM the HOLES.

PWM Power Controller Circuit

This is a circuit that can uses a 555 timer to generate a saw tooth voltage waveform across a capacitor, then compares that signal against a steady voltage provided by a potentiometer, using an op-amp as a comparator. The comparison of these two voltage signals produces a square-wave output from the op-amp, varying in duty cycle according to the potentiometer's position. This is the figure of the circuit; 

This variable duty cycle signal then drives the base of a power transistor, switching current and and off through the load. The 555's oscillation frequency is much higher than the lamp filament's ability to thermally cycle (heat and cool), so any variation in duty cycle, or pulse width, has the effect of controlling the total power dissipated by the load over time. Controlling electrical power through a load by means of quickly switching it on and off, and varying the "on" time, is known as pulse-width modulation, or PWM. It is a very efficient means of controlling electrical power because the controlling element (the power transistor) dissipates comparatively little power in switching on and off, especially if compared to the wasted power dissipated of a rheostat in a similar situation. When the transistor is in cutoff, its power dissipation is zero because there is no current through it. When the transistor is saturated, its dissipation is very low because there is little voltage dropped between collector and emitter while it is conducting current.

PWM is a concept easier understood through experimentation than reading. It would be nice to view the capacitor voltage, potentiometer voltage, and op-amp output waveforms all on one (triple-trace) oscilloscope to see how they relate to one another, and to the load power. However, most of us have no access to a triple-trace oscilloscope, much less any oscilloscope at all, so an alternative method is to slow the 555 oscillator down enough that the three voltages may be compared with a simple DC voltmeter. Replace the 0.1 µF capacitor with one that is 100 µF or larger. This will slow the oscillation frequency down by a factor of at least a thousand, enabling you to measure the capacitor voltage slowly rise over time, and the op-amp output transition from "high" to "low" when the capacitor voltage becomes greater than the potentiometer voltage. With such a slow oscillation frequency, the load power will not be proportioned as before. Rather, the lamp will turn on and off at regular intervals. Feel free to experiment with other capacitor or resistor values to speed up the oscillations enough so the lamp never fully turns on or off, but is "throttled" by quick on-and-off pulsing of the transistor.

555 IC PWM Controller Circuit: Grounded and Ungrounded Load

While keeping the oscillator frequency relatively stable, this 555 based PWM controller features almost 0% to 100% pulse width regulation using the 100k variable resistor. To give a frequency range from about 170Hz to 200Hz , the frequency is dependent on the 100k pot and 100n. This is the figure of the circuit;

You can see the charging and discharging of the 100n cap is done through output pin 3, and this provide a push-pull symmetric drive for easy pulse-width setting. You can see two versions, the left side for grounded load, and the right side for ungrounded load. The grounded one use pin 7 to drive the transistor, while the ungrounded one use the same push-pull output pin3, this difference is needed because wen need an inverted phase to provide consistent potentiometer scale on both version. [Circuit source: talkingelectronics.com]

Precision Clock Conditioners Low-Noise Clock Jitter Cleaner with Cascaded PLLs from the Power Wise

The LMK04000 family of precision clock conditioners provides low-noise jitter cleaning, clock multiplication and distribution without the need for high-performance voltage controlled crystal oscillators (VCXO) module. Using a cascaded PLLatinum architecture combined with an external crystal and varactor diode, the LMK04000 family provides sub-200 femto second (fs) root mean square (RMS) jitter performance. This is the figure of the circuit;

The cascaded architecture consists of two high-performance phase-locked loops (PLL), a low-noise crystal oscillator circuit, and a high-performance voltage controlled oscillator (VCO). The first PLL (PLL1) provides a low-noise jitter cleaner function while the second PLL (PLL2) performs the clock generation. PLL1 can be configured to either work with an external VCXO module or use the integrated crystal oscillator with an external crystal and a varactor diode. When used with a very narrow loop bandwidth, PLL1 uses the superior close-in phase noise (offsets below 50 kHz) of the VCXO module or the crystal to clean the input clock. The output of PLL1 is used as the clean input reference to PLL2 where it locks the integrated VCO. The loop bandwidth of PLL2 can be optimized to clean the far-out phase noise (offsets above 50 kHz) where the integrated VCO outperforms the VCXO module or crystal used in PLL1.

The LMK04000 family features dual redundant inputs, five differential outputs, and an optional default-clock upon power up. The input block is equipped with loss of signal detection and automatic or manual selection of the reference clock. Each clock output consists of a programmable divider, a phase synchronization circuit, a programmable delay, and an LVDS, LVPECL, or LVCMOS output buffer. The default startup clock is available on CLKout2 and it can be used to provide an initial clock for the field-programmable gate array (FPGA) or microcontroller that programs the jitter cleaner during the system power up sequence.

Long Time Delays Circuit with 555 Timer

This is a design circuit for a Long Time Delays using 555 Timer. In 555 Timer, a function of charging rate of the external capacitor is the timing. This circuit needs expensive capacitors with extremely low leakage. Practically, the components limit the time between pulse to around twenty minutes. To get longer time periods, we can connect both halves in tandem with a “divide-by” network in between. This is the figure of the circuit;

The first timer section is operated in an oscillatory mode. The periods of the first timer is 1/Fo. Then the “divide-by-N” network receives this signal and will generate the output signal with period of N/Fo. The second half of the 555 is triggered by the output signal of “divide-by-N”. So, the total time is now a function of Fo and N. 

[Circuit source: Philips Semiconductor Application Note]

PWM Speed Control Circuit Using Forward-Reverse and Regenerative Braking

This is a circuit design for PWM Speed DC Motor Rotation circuit. This circuit has two functions, Forward-Reverse and Regenerative Braking function. This circuit is control by MOSFET. This is the figure of the circuit;

On this circuit, we can control the speed of DC 12V motor with Power MOSFET IRF150 using a signal PWM. The Relay RY1 work as control Reverse with the digital alarm, change Q10. The Relay RY2 work as function brake resistor. The F1 use to protect through the circuit by control Run or stop with the digital alarm. D1 is used to protect the current turn back from DC motor.