This circuit is a doorbell with counter , that means it counts how many times the bell is triggered . It uses a chip synthesizer sound, the HT -2811 ms nothing prevents you from using another device sound generator . The HT -2811 reproduces the sound of a " ding-dong" doorbell . Besides this ic , the circuit includes a CMOS 4026 and Display Driver IC which counts the total number of visitors . Electronic Doorbell with Counter Circuit Diagram
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This circuit automatically turns on a night lamp when bedroom light is switched off. The lamp remains ‘on’ until the light sensor senses daylight in the morning. A super-bright white LED is used as the night lamp. It gives bright and cool light in the room. When the sensor detects the daylight in the morning, a melodious morning alarm sounds. The circuit is powered from a standard 0-9V transformer. Diodes D1 through D4 rectify the AC voltage and the resulting DC voltage is smoothed by C1. Regulator IC 7806 gives regulated 6V DC to the circuit. A battery backup is provided to power the circuit when mains fails. When mains supply is available, the 9V rechargeable battery charges via diode D5 and resistor R1 with a reasonably constant current. In the event of mains failure, the battery automatically takes up the load without any delay. Diode D5 prevents the battery from discharging backwards following the mains failure and diode D6 provides current path from the battery. Automatic Ni...
A simple stereo audio amplifier is built around two 7905 negative-voltage regulators (IC1 and IC2) and a few discrete components. The circuit will also work with other 79XX regulators if appropriate power supply is used. Regulator IC 7905 works as an amplifier for the voltages applied to common pin2 (Ground or GND). Also check the LM317 audio amplifier, another interesting circuit. The minimal voltage drop over the standard 7905 is around 2V and it depends on the output current. Feedback resistors in the IC set the gain of the channel internally. The amplifier is a class-A audio amplifier. The minimal applicable value of R3 for the regulator 7905 is 8.2 to 10 ohms per 5W. Circuit diagram : 1W Stereo Amplifier with Voltage Regulators Circuit Diagram If the required output current for LS1 is below 100 mA, the value of resistor R3 can be 33 to 51 ohms per watt. The circuit works with any load resistance (R3 in parallel with LS1 as the load) under the condition that the regulator is ...
This circuit using IC LA4445 , this is stereo amplifier with power output 2 X 18 Watt, with this circuit you can use to car amplifier or to other elctronics device. Speaker use woofer with impedance 4 Ohm with power up to 20 Watt. Minimum voltagte require 10 Volt and maximum voltage 18 volt. see schematic below : If you can't operate the circuit , please check IC , and then voltage in. If voltage is good check the component are. If components are working . Please check speakers.
*notif : this circuit is stereo power amplifier Although the schematic power amplifier with IC AN7118S is difficult for lees understood making of PCB track . But once tried to design on PCB is not so difficult. Because the actual components close together and easy to design it. This Circuit need minimum voltage 1 volt and maximum voltage 3 volt. It is a low voltage amplifier with power output 2 x 35 m Watt . Schematic circuit below : Click to Enlarge Components Required : Resistor / Condensator / Capacitor : 4,7Ohm (2x) , 0,01 uF (2x) , 47uf (2x) , 68 pf (2x) , 1uF (2x) , 22uF (2x) , 220 uF (1x) , 470uf (2x). Condensator / capacitor voltage use 16 volt. Only Condensator on output speaker use voltage 25 volt.
Simpleclock is an easy to assemble attractive 4-digit 7-segment LED display clock with temperature and alarm function. It is available in three display colors: Red, Blue and White. It comes as a kit of through-the-hole parts and can be soldered by any person with basic soldering experience. An attractive acrylic stand is included. [ ]
This white LED Driver circuit project is based on the NCP5680 high efficiency white LED Driver ic. NCP5680 supports double power flash LED and torch operation . The built-in DC/DC converter is based on a high efficient charge pump structure with 1X, 1.5X and 2X operating modes. The NCP5680 controller is designed to properly drives large external NMOS device with accurate control of the peak current flowing into the LED. Also, the NCP5680 chip includes Open Load and Overload Detection circuit to protect the system against faults at Vout or LED level. High Efficiency White LED Driver Circuit diagram Main features of the NCP5680 are : 2.7 to 5.5 V Input Voltage Range , Dual Power Flash LED Capability , Integrated Overload Protection , Selectable Flash/Torch Mode of Operation , Programmable SuperCAP Re−cycling Current , Capable to Share the DC Voltage to Supply Peripheral Circuits , Indicator LED Function , Integrated Photo Sense Function , Support Camera Strobe , Built−in Short Circuit Pr...
This Circuit must use the IC AN7114 or you can use the IC AN7115 . Minimum voltage for this IC is 6 Volt and maximum voltage is 11 . You can supply this Circuit with 12 Volt if you use IC AN7115 because its maximum voltage 13 volt. Output Power 1 watt with Impedance 4 ohm . See the Schematic (figure 2.0) and package IC ( figure 1.0 ) : Figure 1.0 Figure 2.0
This is a switch circuit using a digital multiplexer 4066 Ic , their keys are ES8 ES1 to 4066 and each contains four switches. When the channel is selected first, and ES1 ES2 ES3 are closed and open, which prevents cross-over between the two channels is the grounding of the channel is not in use. The bandwidth of the multiplex circuit is about 8 MHz and the consumption is 1 mA. When the multiplexer circuit is connected to a load impedance of 75 Ω, the circuit will result in some loss of signal due to internal resistance of the keys. This can be compensated for by connecting an amplifier output. Multiplexer Switch with 4066 Circuit Diagram
Flash Lights with HT2014L This scheme is almost the same with a flash light with LM3909. In this scheme only requires IC HT2014L as a leader, and a resistor and LED. For voltage here need ration power around 4.5 V. You can apply this series to a wider scale in comparing the use IC LM3909. For the scheme are below:
Common electromagnetic relays with coil voltage of 5V, 6V or 12V can operate power circuits in the range of 250 to 300 volts and up to 20A. The actuating current of these relays is in the range of 50 to 100 mA. In many applications, such as temperature-controlled equipment, energisation/de-energisation of 5V, 6V or 12V relays for ‘on’/‘off’ control of the load is to be achieved by a few millivolts. Circuit diagram : Simple Relay Actuating Circuit Diagram Here is a simple relay actuating circuit that can be used to energise relays with a few millivolts as the input. As shown in the figure, the circuit is built around op-amp µA741(IC1) followed by an emitter follower using transistor 2N3440 (T1) and a few discrete components. You can change the sensitivity required (when the input is in millivolts range) to energise the relay by changing the value of resistors R1, R2 and R3. In all the cases, values of R4, R5 and R6 remain unchanged. Resistor R8 is basically a current-limiting res...
Circuit Diagram Description The circuit was designed to create a low cost frequency meter that will cover the range of 1 Hz to 1 MHz with a digital indication using three 7-segment displays. Terminology 7805 – a 3-terminal 1A positive voltage regulator with output transistor safe area compensation, internal short circuit current limiter, output voltage of 5V, 12V, and 15V, internal thermal overload protection, no external components, and current output in excess of 0.5A 4026 – a decade counter where the count advances as the clock input becomes high and has a maximum current of about 1 mA with a 4.5 V supply and 4 mA with a 9 V supply, which can light the appropriate segments of a common cathode 7-segment display 4583 – a 4-bit single-chip microcomputer designed with CMOS technology using a simple, high-speed instruction set, equipped with four 8-bit timers, a 10-bit A/D converter, interrupts, oscillation circuit switch function, and used in application with remote control transmitt...
Car Stereo Audio Amplifier with TDA1553CQ Circuit Diagram This is a stereo audio amplifier for your car. The ambit is powered by a distinct IC TDA1553 with some alien components, this IC will handle your stereo car audio system. The TDA1553CQ is a caked chip class-B achievement amplifier in a 13-lead artificial DIL-bent-SIL ability package. It contains 2×22 W amplifiers in BTL configuration. The accessory is primarily developed for car radio applications. Special features of the device are: 3-state mode switch · standby: low supply current (<100> Loudspeaker protection When a short-circuit to ground occurs, which forces a DC voltage across the loudspeaker of >= V, a built-in protection circuit becomes active and limits the DC voltage across the loudspeaker to <= V. Pin 12 detects the status of the protection circuit (e.g. for diagnostic purposes). Short-circuit protection If any output is short-circuited to ground during the standby mode, it becomes impossible to swit...
This circuit operating with IC uA723 and add amplified with transistor TIP31 or similiar transistor with TIP31 . Input voltage for circuit about 10 - 40 volt DC , formerly of AC voltage 220 volts or 110 volts , then lowered by the transformer voltage to 30 volts. And the supply output voltage from 1 volt to 35 volt DC you can adjust it on potentiometer R2 . See this circuit power supply below : Output voltage transformer used 10 to 40 Volts . On resistor Rsc is the current limit set resistor. Its value is calculated as : Rsc = 0.65 Volt For Example : If you need current output 2.0 A Rsc = 0.65 / 2.0 = 0.32 Ohm So , you must use 0.32 Ohm to current output 2.0 A
This is a simple 30V volt meter using PIC16F676 micro controller with 10-bit ADC (analog to digital converter) and three 7 segment LED displays. You can use this circuit to measure up to 30V DC. The possible applications are on bench power supply or as a digital panel meter in various systems. PIC16F676 is the heart and brain of this circuit. The internal adc of the mcu with a resistor network voltage divider is used to measure the input voltage. Then 3 digits of comm anode 7 segment display is used to display final converted voltage. As you can see in the schematic the displays are multiplexed with each other. It means we switch on one display and put the corresponding digit on this while other two displays are off this cycle goes for each of the displays.
This is the schematic design of HiFi Expandor Circuit with De-emphasis . The circuit is based NE570. The NE570 can be used to construct a high performance compandor suitable for use with music. This type of system can be used for noise reduction in tape recorders, transmission systems, bucket brigade delay lines, and digital audio systems. The circuits to be described contain features which improve performance, but are not required for all applications. HiFi Expandor Circuit Diagram The expandor to complement the compressor is shown in the above circuit. Here an external op amp is used for high slew rate. Both the compressor and expandor have unity gain levels of 0dB. Trim networks are shown for distortion (THD) and DC shift. The distortion trim should be done first, with an input of 0dB at 10kHz. The DC shift should be adjusted for minimum envelope bounce with tone bursts. When applied to consumer tape recorders, the subjective performance of this system is excellent....
If you want to make a flasher unit for you motorbike then this circuit is just for you. This simple turn signal flasher circuit can be easily built and installed in any two wheelers for the desired actions. The circuit employs just two 2-pins instead of 3 as found in other flasher circuits. Once installed, the circuit will faithfully flash the side indicator lights whenever the intended function is switched ON. The circuit also incorporates an optional buzzer circuit which can be also included for getting a beeping sound in response to the flashing of the lamps. . Parts List R1, R2, R3 = 10K R4= 33K T1 = D1351, T2 = BC547, T3 = BC557, C1, C2 = 33uF.25V L1 = Buzzer Coil
Circuit Diagram Description The heart of the circuit is TDA7294 which acts as an amplifier the right and left input feded from the pre amplifier circuit is amplified after passing through the noise filter which contains an RC circuit, the volume is controlled by the variable resistor 47k. and the automatic gain control is provided by the operational amplifier circuit opp amp IC249 For both right channel and left channel., the speaker used is an 8 ohms 40 watts speaker. Source -http://www.electronguide.com/circuits_pages/AudioAmplifier.html