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A 40 watt fluorescent tube lamp or two 20-watt tubes in series will be driven by this circuit but this circuit will produce less brightness than usual, since this circuit only deliver 6-12 Watts. This circuit draws 0.9-1.2 Amps for 2 x 20 watt tubes, or 0.45-0.9A for 1 x 20 watt tube, depending on the potentiometer setting. Here is the schematic diagram of the circuit:

The transformer is wound on a ferrite rod 10mm diameter and 8cm long. The diameter of the wire is fairly critical but has been successfully implemented using 0.28mm wire for all the windings in the prototype. When the circuit is operating, do not remove the tube as the spikes produced by the transformer will damage the transistor.

ICL7107 CD4017 2N3055 LM3914 IRF3205 PT4115 2N2222A
NRF24L01 A1015 DS18B20 ICL7107 NE5532 MC34063 ULN2003

MOC3021 Connection Diagram

One of the control circuit’s triacs selects the tap on main transformer T1, which provides the proper, preregulated voltage to the secondary regulator. T2 and its associated components comprise the second-ary regulator.


The MOC3021is optically isolated triac driver devices. These devices contain a GaAs infrared emitting diode and a light activated silicon bilateral switch, which functions like a triac. They are designed for interfacing between electronic controls and power triacs to control resistive and inductive loads for 240 VAC operations.

The ADO 0804, IC1, digitizes a voltage-feedback signal from the secondary regulator’s output. The MC1415 demultiplexer, IC2, decodes the digitizer’s output. IC2, in turn, drives T1′s optoisolated triacs via the 74LS240 driver chip, IC3, and associated optoisolators.

Transformer T3 samples the circuit’s current output. The auxiliary, 12 V winding on T1 ensures no-load starting. The combination of op amp IC5 and the inverting transistor, Q1, square this current signal. The output of Q1 is the CLK signal, which triggers one-half of the one shot, IC4A, to begin the circuit’s A/D conversion. The one shots’ periods are set to time out within 1/2 cycle of the ac input.

Upon completion of its A/D conversion, IC1′s INTR output triggers the other half of the one shot, IC4B, which enables the converter’s data outputs. The rising edge of the CLK signal resets the one shot and latches the new conversion value into IC2. The latch, associated driver, and optoisolator trigger a selected triac according to the latest value of the voltage-feedback signal, VO.

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ICL7107 CD4017 2N3055 LM3914 IRF3205 PT4115 2N2222A

 Among the final amplifier we called. Regional Power Amp, will it work on several well-known as Class A, Class B, Class AB etc. Each class of the above, to honor the Class A was superior to the sound quality. best. However, class A power output to a low of 20 percent compared with a loss of power or the power consumption of about 5 times the power output. Therefore, the problem of heat Although it has not paid any audio. But anyway, despite the low-watt power, it also provides crystal clear sound quality than Class B and Class AB.

      Principles of integrated amplifier class A is IC1 – NE5532 to extend signal input through the C1 to increase 15-fold. The signal output from the pin 1, signal hemisphere positive through C2 to access Q1-BD139 and Q3-2N3055. is powered by Darling ton, amplifiers and signal the intensification of the negative side of C3 through the amplifier with the Q2-BD140 and Q4-MJ2955. This is the Darling ton, too.

Then the output signal from the positive side of the pin E of the Q3 and the negative side of the pin out of the E in Q4 through R10 and R11, to prevent short circuits and then output to the speakers. This will power up to 5 watts. The D1-D4 acts as a rectifier in the DC bias for Q1 and Q2. And VR1 is adjusted to a constant current bias is at work. The Q1-Q4 will be attached sheet cooled, Q3 and Q4, especially the thermal plate must be large. Because the circuit has high energy loss.

My H-Bridge consume 3ma@3.3v when there is no load and both inputs are zero,

    How can i reduce it ?
    my goal is <100uA
Q2 and Q8 are SS8550 and Q3 and Q9 are SS8050, other Qs are 2N2222A


  The following CD4017 circuits have not been tested and is presented here as a possibility only. If you experiment with this circuit, please send me any problems found so that the circuit can be updated.

  The following circuits are designed to change the duration of each positive output pulse from the astable timer. The circuits use a CD4017 Decade Counter / Decoder to provide nine or ten steps in the cycle.

  The first circuit operates with a repeating ten step cycle. Each output pulse is longer than the previous until a count of ten is reached at which time the cycle will repeat.

  The second circuit has a nine step cycle that stops at the end of the cycle. The cycle is restarted or reset when the RESET input is briefly made high.

  The CD4017 can be configured to give count lengths between 1 and 10. Refer to the timing diagram in the CD4017 data sheet for a better understanding of the IC’s operation.

fixed-point digital, signal processor, LQFP-144, -0.3 V to 4.0 V Supply voltage, -0.3 V to 4.5 V Output voltage TMS320VC5402PGE100 absolute maximum ratings: (1)Supply voltage I/O range, DVDD: -0.3 V to 4.0 V; (2)Supply voltage core range, CVDD: -0.3 V to 2.4 V; (3)Input voltage range, VI: -0.3 V to 4.5 V; (4)Output voltage range, VO: -0.3 V to 4.5 V; (5)Operating case temperature range, TC: -40℃ to 100℃; (6)Storage temperature range, Tstg: -55℃ to 150℃.
TMS320VC5402PGE100 features: (1)Advanced Multibus Architecture With Three Separate 16-Bit Data Memory Buses and One Program Memory Bus; (2)4K x 16-Bit On-Chip ROM; (3)16K x 16-Bit Dual-Access On-Chip RAM; (4)Single-Instruction-Repeat and Block-Repeat Operations for Program Code; (5)Block-Memory-Move Instructions for Efficient Program and Data Management; (6)Instructions With a 32-Bit Long Word Operand; (7)Instructions With Two- or Three-Operand Reads; (8)Arithmetic Instructions With Parallel Store and Parallel Load; (9)Conditional Store Instructions; (10)Fast Return From Interrupt; (11)CLKOUT Off Control to Disable CLKOUT.

The TMS320VC5402PGE100 fixed-point, digital signal processor (DSP) (hereafter referred to as the 5402 unless otherwise specified) is based on an advanced modified Harvard architecture that has one program memory bus and three data memory buses. This processor provides an arithmetic logic unit (ALU) with a high degree of parallelism, application-specific hardware logic, on-chip memory, and additional on-chip peripherals. The basis of the operational flexibility and speed of this DSP is a highly specialized instruction set.

This is Logic Digital Tester Circuit. It uses the level input about 5V and use the integrated circuit LM324. Be Main Part electronics perform Drive All LED. Then use Current very low about 10mA by have potentiometer be formed fine the value threshold give just right with the level logic digital both of 3 the level that use by LED1(Green) be the level high and LED2(Red) Be the level LOW and The LED3(Yellow) be the level High IMR . The detail is other please see in the circuit please .


The MAX705CSA is a microprocessor (μP) supervisory circuit which reduces the complexity and number of components required to monitor power-supply and battery functions in μP systems. The device significantly improves system reliability and accuracy compared to separate ICs or discrete components. The applications of the MAX705CSA include Computers, Controllers, Intelligent Instruments, Automotive Systems, Critical μP Power Monitoring.
MAX705CSA absolute maximum ratings: (1)VCC: -0.3V to 6.0V; (2)All Other Inputs: -0.3V to (VCC + 0.3V); (3)Input Current, VCC: 20mA; GND: 20mA; (4)Output Current (all outputs): 20mA; (5)Continuous Power Dissipation, Plastic DIP (derate 9.09mW/℃ above +70℃): 727mW.
MAX705CSA features: (1)μMAX Package: Smallest 8-Pin SO; (2)Guaranteed RESET Valid at VCC = 1V; (3)Precision Supply-Voltage Monitor, 4.65V in MAX705/MAX707/MAX813L; 4.40V in MAX706/MAX708; (4)200ms Reset Pulse Width; (5)Debounced TTL/CMOS-Compatible Manual-Reset Input; (6)Independent Watchdog Timer—1.6sec Timeout (MAX705/MAX706); (7)Active-High Reset Output (MAX707/MAX708/MAX813L); (8)Voltage Monitor for Power-Fail or Low-Battery Warning.


We used a Microchip PIC24FJ64GA002 28pin SOIC microcontroller (IC1) in this project. The power pins have 0.1uF bypass capacitors to ground (C1,2). The 2.5volt internal regulator requires a 10uF tantalum capacitor (C20). The chip is programmed through a five pin header (ICSP). A 2K pull-up resistor (R1) is required for the MCLR function on pin 1. Read more about this chip in our PIC24F introduction.

An inexpensive MAX3232CSE RS232 transceiver (IC2) interfaces the PIC to a PC serial port. This chip replaces the expensive through-hole MAX3223EEPP+ used in the previous version of the Bus Pirate. The serial interface will work with a USB->serial adapter.

I know how to build a big digit but how the heck did you control that much current with such few ICs and such few control lines? Ahh, I’m glad you asked. Here are some fun pointers about how to control large numbers of seven segments LEDs.

Now if you’re not a hardware person, get ready for some technical jargon.

A PIC 16F877A has quite a few I/O pins (around 32). But if you start doing the math, you see just how limited we are.

6 digits * 7 segments = 42 channels

Sure, we could find a microcontroller that has 42 available I/O pins, but there’s got to be a better way! This is actually an age-old problem. Turns out there are chips out there! The 74HC4511 is the magical chip that takes a Binary-Coded-Decimal (BCD) input and outputs the correct pins to create that binary number on a seven-segment display.

Okay, so we go from seven lines down to four, big deal? There is a latch on the 74HC4511. This latch allows us to share the 4-bit bus with all the channels, and then just toggle the latch pin on the digit we need to talk to. Maybe a schematic will help:


You can see four Control lines. This is the BCD bus. There is also six Driver lines. These Driver lines activate the latch on each ‘channel’.

U6 is the 74HC4511. U7 is a ULN2003A. JP1 is the RJ45 jack. Just stick with me a bit longer!

The ULN2003A is a high-current Darlington array. Darling what? This IC has seven channels. Each channel can control up to 500mA. When 1B goes high, current is allowed from the ’1C’ input to ground.

So when the Num1_f pin goes high, current flows from RAW, through the LED Light Bars in the big digit, into 1C, and then out through GND. This may seem a little bit odd at first. Maybe this will help:

Okay so now for the chain of events.

The PIC parses out the GPS time from NMEA sentences coming out of the Lassen iQ receiver at 4800bps.
The PIC decides that the time is 6:45:33, so a ’3′ needs to be displayed on channel 1.
A binary three (0b.0011) is put onto the bus.
Driver1 is pulled low, then driven high. Because all other driver lines are kept high, the other drivers ignore this bus data.
The 74HC4511 for channel 1 sees this binary number, notices that it’s been latched, and then outputs the correct segments to light up a three. Segments A, B, C, D, and G go high.
The ULN2003A detects these lines (Num1_a, b, c, d and g), goes high and allows current to sink through 3C, 4C, 5C, 6C, and 2C.
The LED Light Bars inside the digit (located farthest to the right) light up the correct bars to display a three.

It’s really pretty slick. The system is completely scalable. To add another seven-segment display requires only one additional I/O pin for another DriverX line. The PIC 16F877A could control as many as 28 digits. Have you ever seen 28 digits next to each other? How about 18″ wide and on a wall? That’s really huge.

That’s it! Sorry the tutorial ended up being so long. This project took about two weeks of cutting and figuring out how to best create the digits. The firmware took about an hour and hardware layout took about three (we’ve used most of the basic components before). Let us know what you think.


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