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Digital Echo Processor IC PT2399 is using CMOS technology in audio purposes. Digital Echo Processor PT2399 is implementing the system in the process of ADC and DAC audio repro echo.


Digital Echo Processor PT2399 has a high sampling frequency and 44K memory. Digital Echo Processor PT2399 to repro echo digital audio system of repro VCO delay time system that can be arranged. Digital Echo Processor PT2399 has a very low audio distortion of (THD <0.5%) and very low noise as well (No <-90dBV) so that the Digital Echo Processor PT2399 is capable of providing good audio quality.

Digital visitor counter is a reliable circuit that takes over the task of counting Number of Persons/ Visitors in the Room very Accurately. When somebody enters into the Room then the Counter is Incremented by one and when any one leaves the room then the Counter is Decremented by One. The total number of Persons inside the Room is displayed on the seven segment displays. The microcontroller do the above job it receives the signals from the sensors, and this signals operated under the control of software which is stored in ROM.

A electronic acquaintances was seeking a star as circuits in vogue your at no cost point in time,a shameful and uncomplicated to made.This dice digital circuit would occur a favorite of all and sundry, by using it to flaunt the records. As you switch to a spin button before it like is tossing a dice. Looks like a random form normally.

A focal point of this circuit,an a secure oscillator 1Khz with IC 555 and RC networks,it resolve be located output to IC2 is Decade counter IC - 4017. After I focus inedible the spin switch, it will be converted to a binary input with a diode matrix D1-D9 (1N4148 before numeral 1N914) and so therefore untouched to a 7 segment put on show with a decoder drive IC refusal. CD4511 (IC3). The brightness of the numeric display, may well occur customized by adjusting the quantity of R3.

Amplifier with digital volume control can we make predictably because the circuit is made simple with just single chip TDA8551. The series of Mini Amplifier With Digital Volume Control is a type BTL amplifier with 1 Watt.



Techniques for adjusting the volume in this series has been provided with a pin path control that is controlled by providing an input voltage VCC and GND. The series is also equipped with a selector mute, standby and operating.

Digital Audio Processor TDA 7309 is a stereo audio processor with independent volume control of each channel was to get the audio quality of a good processor. Digital Audio Processor TDA 7309 is equipped with a loudness control is controlled externally. Digital Audio Processor TDA 7309 also has a soft mute feature stand-alone for each canals. Digital Audio Processor TDA 7309 is controlled via the I2C serial bus system with a microcontroller interface. 

Block Diagram of Digital Audio Processor TDA 7309 Feature-owned Digital Audio Processor TDA 7309 The input multiplexer with 3 stereo input Recording function on the output line Loudnes external ontrol Independent volume control Digital volume control with 1dB step Soft Mute All functions of the Digital Audio Processor TDA 7309 is programmed via the I2C serial bus system

Amplifier with digital volume control can we make predictably because the circuit is made simple with just single chip TDA8551. The series of Mini Amplifier With Digital Volume Control is a type BTL amplifier with 1 Watt.



Techniques for adjusting the volume in this series has been provided with a pin path control that is controlled by providing an input voltage VCC and GND. The series is also equipped with a selector mute, standby and operating.

The circuit diagram on behalf of the digital watch. 2x16 LCD is connected to the docks 2 of AT89C51. P1.0 of uC force provide the SCL (entertainment in installments clock) and P1.1 SDA (serial data) for I2C message.

Nearby are four switches connected to the uC, having the status of given away within the think. Function of the keys are same as unmistakable from their names.

at what time the power supply is switched on it willpower confer you the default appointment and schedule, but anon you can convert it to the desired appraise. taking into account setting as soon as, the backup battery will keep the timepiece ticking even after the power is not near.

A trivial a propos I2C:

There are basically four most important conditions wearing I2C protocol.

1) Start Condition

2)block Condition

3)Data Validity

4)Acknowledgement

1)Start Condition:

while SCL is sharp and SDA H->L, force take place taken since start condition meant for the exchange of ideas.

2)Stop Condition:

once SCL is high and SDA L->H, will generate a stop condition.

3)Data Validity:

after SCL is high at hand must be refusal chande voguish SDA line lone followed by the data is legally binding, the data loose change be supposed to be there made only as SCL is low.

4)Acknowledgement:

taking into account transfer of lone byte of data the reciever has to acknowledge the sender pro the winning reception. for this the sender add up to the SDA line soaring and reciever pulls down the SDA low, which tells the sender so as to data has reached safely.

his clock timer uses a PIC16F628 microcontroller to display 3 and 1/2 digit time and control an external load. The clock includes a calendar with leap year and optional daylight savings adjustments. The timer output can be set from 1 to 59 minutes and manually switched on and off. The clock also has a correction feature that allows an additional second to be added every so many hours to compensate for a slightly slow running oscillator.  The oscillator uses a common 32.768 KHz watch crystal and the frequency can be adjusted slightly with the 24pF capacitor on the right side of the crystal.

There are 7 displays that advance each time the D switch is toggled. To make adjustments, set the RA5 switch to the "B" position and then toggle the E and F switches to advance the data in the hours or minutes digits. Then toggle the "D" switch to move to the next data. After the 7th display, it will go back to the top and display the current time. Or, just press the time switch C to get to the top at anytime. When done setting everything up, set the RA5 switch to the "A" position so the data cannot be accendentally changed. You can still view everything with the "D" advance key, but the E an F switches will just turn on or off the alarm at RB7. I use it with an external transistor to switch on and off a radio.

PIC Digital Clock Timer Circuit Diagram

The Daylight savings setting (in the 6th display in the minutes digits) is used to enable daylight savings time adjustments, one hour ahead on the 2nd sunday in March, and one hour behind on the first sunday in November. The entry will be either 0, 1, or 3.

0 = Daylight savings time disabled (default).
1 = Savings time enabled and current time is standard time.
3 = Savings time enabled and current time is daylight savings time.

The last 2 entries on the list (Year and Correction) is for the current year (1 to 4) (4 = Leapyear) so todays setting (2006) will be 2 since leapyear will be on year 4 which is 2 years from now. The correction setting will add a second every so many hours for fine adjustment to the oscillator frequency. My setting is 18 which adds a second every 18 hours. Its pretty accurate and only loses 3 seconds a month. You probably want to run it for a couple weeks to figure out what correction is needed for the crystal you have.

Switch functions:

RA0         (C switch)         =  Display Time
RA1         (D switch)         =  Advance to next data (alarm, calendar, etc)
RA2, RA3    (E and F switch)   =  Advance hours and minutes (in setup mode).
RA2, RA3    (E and F switch)   =  Toggle alarm output on/off (in run mode)
RA5 in the B position (open) =  Setup Mode

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Digital Thermometer 0-100.0°C is a digital thermometer that operates in modetemperature measurement in Celsius (° C). Digital Thermometer 0-100.0 ° C in this article uses data processor in the form of a microcontroller AT89C4051.



Temperature sensors used in Digital Thermometer 0-100.0 ° C. This temperature sensor LM35D. Digital Thermometer 0-100.0 ° C. It uses the temperature measurement data viewer in the form of 1 line LCD viewer. Digital Thermometer 0-100.0 ° C. It can display the temperature measurement data with a resolution of 0.1 ° C.

Digital Thermometer 0-100.0 ° C. These temperature sensors make use of LM35D as temperature sensing. In Digital Thermometer 0-100.0 ° C. This temperature sensor measurement data this LM35D (Level Voltage) is then converted into 4-bit binary data using the ADC CA3162.

Then the 4-bit data from ADC CA3162 which is a measurement of data if the temperature is in the AT89C4951 microcontroller so that it becomes an operating principle of temperature measurement based on digital thermometers. In the final stage of the Digital Thermometer 0-100.0 ° C. This is the appearance of digital data temperature measurement, using digital data viewer of the LCD 1 line.

Digital Echo Processor IC PT2399 is using CMOS technology in audio purposes. Digital Echo Processor PT2399 is implementing the system in the process of ADC and DAC audio repro echo.


Digital Echo Processor PT2399 has a high sampling frequency and 44K memory. Digital Echo Processor PT2399 to repro echo digital audio system of repro VCO delay time system that can be arranged. Digital Echo Processor PT2399 has a very low audio distortion of (THD <0.5%) and very low noise as well (No <-90dBV) so that the Digital Echo Processor PT2399 is capable of providing good audio quality.

Digital Thermometer 0-100.0°C is a digital thermometer that operates in modetemperature measurement in Celsius (° C). Digital Thermometer 0-100.0 ° C in this article uses data processor in the form of a microcontroller AT89C4051.



Temperature sensors used in Digital Thermometer 0-100.0 ° C. This temperature sensor LM35D. Digital Thermometer 0-100.0 ° C. It uses the temperature measurement data viewer in the form of 1 line LCD viewer. Digital Thermometer 0-100.0 ° C. It can display the temperature measurement data with a resolution of 0.1 ° C.

Digital Thermometer 0-100.0 ° C. These temperature sensors make use of LM35D as temperature sensing. In Digital Thermometer 0-100.0 ° C. This temperature sensor measurement data this LM35D (Level Voltage) is then converted into 4-bit binary data using the ADC CA3162.

Then the 4-bit data from ADC CA3162 which is a measurement of data if the temperature is in the AT89C4951 microcontroller so that it becomes an operating principle of temperature measurement based on digital thermometers. In the final stage of the Digital Thermometer 0-100.0 ° C. This is the appearance of digital data temperature measurement, using digital data viewer of the LCD 1 line.