Circuit Wiring Solution: switch

Showing posts with label switch. Show all posts

Saturday, November 8, 2014

Dark Sensitive Power Switch Circuit Diagram Using LDR

DescriptionCircuit showing a Dark Sensitive Power Switch .Here we have used a ldr and a ordinary transistor for making this circuit
.Connect any 230 volt equipment at the load .You need a 9 volt power supply
Components Required

Resistor 10 k , 680 R

Transistor BC 548

Diode IN 4007

Relay LDR

Thursday, October 9, 2014

Touch Switch Circuit with explnation

This electronic circuit uses a 555 timer as the bases of the touch switch. You can learn more about 555 timers in the Learning section on my site. When the plate is touched the 555 timer is triggered and the output on pin 3 goes high turning on the LED and the buzzer for a certain period of time. The time that the LED and the buzzer is on is based on the values of the capacitor and resistor connected to pin 6 & 7. The 10M resistor on pin 2 causes the the circuit to be very sensitive to the touch.

Friday, September 12, 2014

Simple Touch Switch

With touch switch, you can turn on and turn on a electronic device. Touch switch dont need mechanical part, so they will not worn out due to mechanical contact. Touch switches can be used in places where regular switches would not last, such as wet or very dusty areas.

Here the schematic diagram:

Component part list:


Part Total Qty. Description

C1 1 10uF 16V Electrolytic Capacitor
R1, R2 2 100K 1/4 Watt Resistor
R3 1 10 Meg 1/4 Watt Resistor
U1 1 4011 CMOS NAND Gate IC
MISC 1 Board, Wire, Socket For U1

Notes:

1. The contacts an be made with just two loops of wire close together, or two squares etched close together on a PC board.

2. When activated, the output of the schema goes high for about one second. This pulse can be used to drive a relay, transistor, other logic, etc.

3. You can vary the length of the output pulse by using a smaller or larger capacitor for C1.

Thursday, September 4, 2014

Automatic headlight dim switch

With this cool schema integrated to your cars headlight system , you can drive cool headed in high beam.The schema will take over the duty of low beaming the headlight when vehicles approach against , and high beams the lights when they pass over.

The schema is based on a photo transistor(Q1) for sensing the approaching vehicles and transistor Q2 (BC177) for switching the relays for controlling the headlight.When the light from the opposite vehicle falls on Q2 , it’s collector current increases and turns ON Q1.The relay will be activated and the head light will be dimmed.When the vehicle pass over the reverse will happen.

Notes.

* The battery B1 can be the 12V car battery itself.
* Adjust POT’s R1,R2,R4 to obtain optimum performance.
* The Q1 can be any general purpose PNP photo transistor.It should be mounted in front of the car so that the light from opposite vehicle easily falls on it.
* Relay contact A goes to high beam schema,B to low beam schema and C is the common point.
* Carefully understand the wiring of your car before attempting to install the schema.Wrong connections could easily bring trouble to your cars wiring.

Automatic Load Sensing Power Switch

This schema will automatically switch on several mains-powered "slave" loads when a "master" load is turned on. For example, it will switch on the amplifier and CD player in a stereo system when the receiver is turned on. It works by sensing the current draw of the "master" device through a low value high wattage resistor using a comparator. The output of that comparator then switches on the "slave" relay. The schema can be built into a power bar, extension cord or power center to provide a convenient set of "smart" outlets that switch on when the master appliance is powered (turn on the computer monitor and the computer, printer and other peripherals come on as well).

Automatic Load Sensing Power Switch Circuit diagram

Parts List

Part	Total Qty.	Description
C1, C3	2	10uF 35V Electrolytic Capacitor
C2	1	1uF 35V Electrolytic Capacitor
R1	1	0.1 Ohm 10W Resistor
R2	1	27K 1/2W Resistor
R3, R4	1	1K 1/4W Resistor
R5	1	470K 1/4W Resistor
R6	1	4.7K 1/2W Resistor
R7	1	10K 1/4W Resistor
D1, D2, D4	3	1N4004 Rectifier Diode
D3	1	1N4744 15V 1 Watt Zener Diode
U1	1	LM358N Dual Op Amp IC
Q1	1	2N3904 NPN Transistor
K1	1	Relay, 12VDC Coil, 120VAC 10A Contacts
S1	1	SPST Switch 120AVC, 10A
MISC	1	Board, Wire, Socket For U1, Case, Mains Plug, Socket

Notes

This schema is designed for 120V operation. For 240V operation, resistors R2 and R6 will need to be changed.
A maximum of 5A can be used as the master unless the wattage of R1 is increased S1 provides a manual bypass switch.
THis schema is not isolated from the mains supply. Because of this, you must exercise extreme caution when working around the schema if it is plugged in.

Tuesday, September 2, 2014

Light activated switch circuit

This schema is well important schema for us because We can get lots of advantages through this schema.When the light puts on L.D.R the schema activates.So you can use this one as you morning alarm or you can use this one for your robot.

Note

# You can use either a 12 V battery or a well regulated & filtered 12V DC mains operated power supply.

# The pin 5&6 (Balance & Balance/Strobe ) of IC LM311 are shorted to minimize the chance of oscillations.

Saturday, August 30, 2014

Toggle switch with Infra Red IR

Toggle switch in this article is a series of toggle switches that are controlled by infrared light. The series toggle switch is made from a combination of data flip-flop CD4013 2 units.
Receiver circuit of the infrared light signals arranged with infrared receiver as found on television remote receiver. Infrared signal from remote is used as clock signals and data to the data flip-flop first. then the second flip-flop data set as a toggle flip-flop toggle the output signal is used to drive the relay. for more details can be seen in thethe following image .

Series Toggle Switch With Infra Red (IR) that is required to supply voltage range of 12VDC and the output of Toggle Switch With Infra Red (IR) is dapt used to turn on the lights or other electronic devices with DC or AC voltage source. Series Toggle Switch With Infra Red (IR) was isolated from the load that is placed for use as the final relay.

Tuesday, August 26, 2014

CELL PHONE CONTROLLED AUDIO VIDEO MUTE SWITCH

This cell-phone-controlled audio/video mute switch is highly useful in automobiles. The schema automatically disconnects power supply to the audio/video system whenever the mobile handset is lifted off the holder for making or receiving a call. You can use any readily available cell-phone holder with some minor alterations or fabricate it yourself as shown in Fig. 1.

http://streampowers.blogspot.com/2014/02/cell-phone-controlled-audio-video-mute.html

Fig. 1: Proposed cell-phone holder

The schema is wired around IC LM555 (IC1), the CMOS version of timer NE555, as shown in Fig. 2. IC1 is used as a medium-current line driver with either an inverting or non-inverting output. It can sink (or source) current of up to 50 mA only, so take care while handling it. The audio/video system is connected to the schema via normally opened (N/O) contacts of the relay.

Fig. 2: The schema of the cell phone-controlled audio/video mute switch

When the cell phone is in its holder, LDR1 does not receive any light from white LED1 and its resistance is high. As a result, the voltage at pin 2 of IC1 remains high to provide a low output at pin 3. The low output of IC1 activates relay RL1 and the audio/video system gets power supply via its N/O contacts. LED3 glows to indicate that the audio/video system is ‘on.’When the handset is taken off the holder, light rays from LED1 fall on LDR1 and its resistance decreases. As a result, the voltage at pin 2 of IC1 decreases to provide a high output at its pin 3. The high output of IC1 deactivates relay RL1 and the audio/video system does not get power supply. LED2 glows to indicate that the audio/video system is ‘off.’

Preset VR1 is used to control the sensitivity of the schema. Zener diode ZD1 is used for protecting white LED1 from the higher voltage. The schema works off a 12V car battery. Switch S1 can be used to manually switch on/off the audio/video system.

Sourced By: EFY Author name: T.K. HAREENDRAN

Saturday, August 23, 2014

Simple Automatic Switch For Audio Power Amplifier

Simple Automatic Switch For Audio Power Amplifier Circuit of an automatic switch for audio power amplifier stage is presented here. The schema uses stereo preamplifier output to detect the presence of audio to switch the audio power amplifier on only when audio is present. The schema thus helps curtail power wastage. IC1 is used as an inverting adder. The input signals from left and right channels are combined to form a common signal for IC2, which is used as an open loop comparator. IC3 (NE556) is a dual timer. Its second section, i.e., IC3(b), is configured as monostable multivibrator. Output of IC3(b) is used to switch the power amplifier on or off through a Darlington pair formed by transistors T1 and T2. IC3(a) is used to trigger the monostable multivibrator whenever an input signal is sensed.

Circuit diagram:

Automatic Switch For Audio Power Amplifier Circuit Diagram

Under ‘no signal’ condition, pin 3 of IC2 is negative with respect to its pin 2. Hence the output of IC2 is low and as a result output of IC3(a) is high. Since there is no trigger at pin 8 of IC3(b), the output of IC3(b) will be low and the amplifier will be off. When an input singal is applied to IC1, IC2 converts the inverted sum of the input signals into a rectangular waveform by comparing it with a constant voltage which can be controlled by varying potentiometer VR1. When the output of IC2 is high, output pin 5 of IC3 goes low, thus triggering the monostable multivibrator. As soon as the audio input to IC1 stops, pin 5 of IC3 goes high and pin 1 of IC3 discharges through capacitor C3, thus resetting the monostable multivibrator.

Hence, as long as input signals are applied, the amplifier remains ‘on.’ When the input signals are removed, i.e., when signal level is zero, the amplifier switches off after the mono flip-flop delay period determined by the values of resistor R8 and capacitor C3. If no input signals are sensed within this time, the amplifier turns off—else it remains on. Power supply for the schema can be obtained from the power supply of the amplifier. Hence, the schema can be permanently fitted in the amplifier box itself. The main switch of the amplifier should be always kept on. Resistors R1 and R2 are used to divide single voltage supply into two equal parts.

Capacitors C1 and C2 are used as regulators and also as an AC bypass for input signals. Diode D1 is used so that loading fluctuations in power amplifier do not affect schema regulation. Transisitor T2 acts as a high voltage switch which may be replaced by any other high voltage switching transistor satisfying amplifier current requirements. Value of resistor R10 should be modified for large current requirement. The LED glows when the amplifier is on. The schema is very useful and relieves one from putting the amplifier on and off every time one plays a cassette or radio etc.

Source : EFY

Monday, August 18, 2014

2 x 6W CAR RADIO AMPLIFIER PLUS SOLID STATE SWITCH TDA7365

General Description

OUTPUT POWER 2x6W/4Ω @14.4V, 1KHz, 10%
SOLID STATE POWER SWITCH INCLUDED (1A @ VDROP = 0.8V Typ.)
MINIMUM EXTERNAL COMPONENT COUNT
- INTERNALLY FIXED GAIN (40dB)
- NO BOOTSTRAP CAPACITORS
- NO EXTERNAL COMPENSATION
ST-BY FUNCTION (CMOS COMPATIBLE)
MUTE FUNCTION (CMOS COMPATIBLE)
NO AUDIBLE POP DURING MUTE/ST-BY
OPERATIONS
LOW SUPPLY SELF MUTING
PROTECTIONS
AC AUDIO OUTPUTS SHORT CIRCUIT TO GND
DC AUDIO OUTPUTS SHORT CIRCUIT TO
GND AND TO VS AT POWER ON
SWITCH OUTPUT INTERNAL CURRENT LIMITATION
OVERRATING CHIP TEMPERATURE WITH
SOFT THERMAL LIMITER
LOAD DUMP
FORTUITOUS OPEN GND

Circuit diagram:

2 x 6W CAR RADIO AMPLIFIER PLUS SOLID STATE SWITCH