ffd

What i am making here is a USB lock with smartcard key. The idea is that a phonecard reader made with a PIC micro will be able to store a number of different phonecards into memory. Whenever one of these cards is inserted into the slot, it will activate a 4-ports USB On/Off switch. If the card is removed, the USB ports will be de-activated. [ ]

USB Battery Charger For Lithium Ion battery with the LM3622 is a series of lithium ion battery charger. This charger circuit operates using power from the USB source PC. Current consumption of a series of USB Battery Charger For Lithium Ion battery with 400mA LM3622 is limited by R1, so it does not exceed the current maximum limit that can be given by a USB computer. Brains from USB Battery Charger For Lithium Ion battery with IC LM3622 , it is a national of having special technical specification charger for lithium ion batteries. In a series of USB Battery Charger For Lithium Ion with LM3622 R1 0.25 Ohm value that serves to limit the charging current 400mA to the battery. Q2 and Q1 is the last part of the USB Battery Charger For Lithium Ion battery with the LM3622. In principle, USB Battery Charger For Lithium Ion with LM3622 identify the condition of the battery full charged battery voltage via pin 6 LM3622. USB Series Lithium Ion Battery Charger For LM3622 is equipped with a switch ...

This really a work that so cool if you like modif PC. So this is a USB interface for alphanumeric LCD display like 4 × 20 which can be controlled with LCD Smartie program. USB interface is implemented by using PIC18F2550 microcontroller, Using USB LCD modules. Below is a project of the USB LCD controller. Schematic circuit and PCB design source  | link

The objective of a remote control is to have the ability to operate a device from a certain distance. Nevertheless, remote controls usually are in places where we need to move around to find. This makes the remote totally useless as you may have used that time and energy to operate the device personally. If we take into account the limited reach that remote have, along with the fact that they are battery operated, we have an obsolete technology. All this can be fixed by developing a new remote control system. A lot of designs have been completed on systems that operate by clapping. But they have some disadvantages. Such as the fact that they work over only one sound or command. Another fact is that daily activities must be interrupted to give a command. A whistling command system has been developed to control domestic devices. It works by detecting the sound peaks that are uniquely produced by whistles. Sound from each whistle is processed to give the order to the device....

Procyon is a general purpose development board with special features for Ethernet, USB, and audio applications. It is based on Luminary Micro/Texas Instruments LM3S9x9x series of parts. The initial MCU is LM3S9B90. The board contains the following features: 80 MHz, 100 Pin Cortex M3 Processor 16 MB SDRAM accessed on a 50 MHz EPI bus USB Host/Device/OTG port microSD card slot (Attached to SSI1/SPI1) 10/100 Ethernet I2S header for DAC output interface Up to 24 GPIOs available 3 UART, 2 I2C, 1 CAN, 2 SPI/SSI (one shared with microSD card) 10-bit ADCs General purpose timers: four 32-bit or eight 16-bit FTDI/Basic UART debug/program interface, on 16 pin GPIO/configuration header Three 10 pin headers for daughter boards 20 Pin JTAG Header User LED and User switch [ ]

Modifying USB OTG Cable - Mini USB - micro This is a very simple way to change the standart USB to USB OTG. The Mini or Micro USB to USB does not work if you want to use it for OTG, because 4. pin micro USB plug is not plugged. Connect as shown above.

Green USB switch Circuit Diagram. According to the Energy Saving  Trust, if you add up all the current drawn in standby mode by items such as stereos, TVs, VCRs and DVDs over a year in the UK alone, it amounts to 3.1 million tonnes of CO2 released into the atmosphere.This is without factoring in the current drawn by all the PCs,laptops and their associated peripherals left in standby mode.  Green USB switch Circuit Diagram Green USB switch Circuit Diagram It  is  not  necessary  to  spend  a  great deal of money or time to  make a difference on a personal  level. The circuit described here  is designed for use by laptop or  notebook computers. It will automatically switch off all mains  powered peripheral equipment  including monitor, printer, scanner, TV tuner and USB hub etc  when it detects that the notebook  is switched off. The circuit is quite  straightforward; in addition to an  opto...

One tool that I’ve been missing at my lab at home is function generator. They tend to be a bit expensive, so I haven’t bought one. I thought this might be a good opportunity to try and make one myself. I found a pretty common DDS (direct digital synthesis) chip, called AD9833. Then just strap a USB-enabled AVR micro there and maybe some analog electronics. This board doesn’t do any of the special analog magic to allow for variable amplitude or offset for the signal. The output is fixed to 0-4v. I’m planning to make another completely analog board for adjusting amplitude and offset.

Create USB PowerInjector for GSM Modem Maximizing and stabilization USB voltage . Sometimes we need also to extend the USB cable connection. Usually cable so the store is no more or less than one meter. If the cable is good quality automatic reduction of voltage and current remain so flash media or a modem to function remained normal. Sometimes the two media are not readable because of a decline in flow due to cable resistance is very large, so that lost power wasted. USB injector circuit If this happens often flash or USB modem off often error-disconnected. To overcome this decrease in voltage performance. The principle is quite very simple. You simply "inject" is indeed voltage VCC 5VDC needed a modem or a flash. Finishing USB inject After using the USB power injector is expected regardless of the length of external cable fixed voltage maximum. The principle works is simple enough original 5VDC voltage of the CPU / your computer off and then injected...

This simple circuit can be used to program the PIC16F84 and similar "flash memory" type parts. It uses a cheap 555 timer IC to generate the programming voltage from a +5V rail, allowing the circuit to be powered from a computer’s USB port. The 555 timer (IC1) is configured as a free-running oscillator, with a frequency of about 6.5kHz. The output of the timer drives four 100nF capacitors and 1N4148 diodes wir-ed in a Cockroft-Walton voltage multiplier configuration. USB-Powered PIC Programmer Circuit Diagram The output of the multiplier is switched through to the MCLR/Vpp pin of the PIC during programming via a 4N28 optocoupler. Diodes ZD1 and D5 between the MCLR/Vpp pin and ground clamp the output of the multiplier to about 13.6V, ensuring that the maximum input voltage (Vihh) of the PIC is not exceeded. A 100kΩ resistor pulls the pin down to a valid logic low level (Vil) when the optocoupler is not conducting. The circuit is compatible with the popular "JDM" progr...

Creating a sound card is not more complex problems. If you use Great IC PCM2702 from Burr RED / Texas Instruments you can create a card USB sound fully functional. The sound card can be activated from the USB port and has one stereo output. You do not need to install drivers for Windows XP and Vista, because the driver is already in the system, XP and Vista. So this series is really plug and play. Block Diagram Description The core of this construction is a 16-Bit Stereo Digital-To-Analog Converter with PCM2702 USB interface. Schematic diagram USB soundcard PCM2702 only requires a few additional components to work. This scheme is not complex. The sound card can be activated directly from the USB port (jumper W1) or from an external power supply (jumper W3). PCM2702 requires two 3.3V power supply (3V-3.6V) and 5V (4.5V-5.5V). I use a fixed output voltage to 3.3V LDO TPS76733Q (IO2) and the output voltage is adjusted to 5V LDO TPS76701Q (IO3). LDO Both are produce...

Looking for a unique gift? Here’s an antique typewriter which has been modified to function as a USB Keyboard for PC, Mac, or even iPad. That’s very cool, isn’t it? In the world of obsolescence, this USB typewriter is a groundbreaking innovation. It does not change the outward appearance of the typewriter and is easy to install since there is no messy wiring. The 3 components of the USB typewriter are the Sensor board, the USB switches, and the Reed Switches. It works like a regular typewriter with all letters, numerals, and punctuation marks as well as shift, space, and return carriage. It’s a better addition to your home office.

The Pocket Voltage Supply is a USB powered variable voltage supply. It can be powered with any 5V USB hub and can supply up to 1.5A. 5V USB hubs can be found almost anywhere; desktop computers, laptops, cell phone chargers, even portable USB battery banks. Pairing the Pocket Voltage Supply with a portable USB battery bank allows the user to test circuits and prototypes outside of a lab setting and even bring testing to the field! [ ]

A common problem when an AC mains adapter is used to power a USB device is that the voltage does not match the nominal 5 V specified by the USB standard. The circuit shown here accepts an input voltage in the range of 4-9 V and converts it into a 6-V output voltage, which is then stabilized to a clean 5-V level by a series regulator. The combined boost/buck converter used here operates on the SEPIC principle. That principle is quite similar to the operating principle of the Cuk converter, but without the disadvantage of a negative output voltage. Circuit diagram : Stable USB Power Supply Circuit Diagram The circuit is built around a MAX668, which is intended to be used as a controller for boost converters. The difference between a SEPIC converter and a standard boost (step-up) converter is that the former type has an additional capacitor (in this case C2) and a second inductor (in this case, the secondary winding of transformer L1). If C2 is replaced by a wire bridge and the secondary...

According to the Energy Saving  Trust, if you add up all the current drawn in standby mode by items such as stereos, TVs, VCRs and DVDs over a year in the UK alone, it amounts to 3.1 million tonnes of CO2 released into the atmosphere.This is without factoring in the current drawn by all the PCs,laptops and their associated peripherals left in standby mode. Circuit diagram : Green USB switch Circuit Diagram It  is  not  necessary  to  spend  a  great deal of money or time to  make a difference on a personal  level. The circuit described here  is designed for use by laptop or  notebook computers. It will automatically switch off all mains  powered peripheral equipment  including monitor, printer, scanner, TV tuner and USB hub etc  when it detects that the notebook  is switched off. The circuit is quite  straightforward; in addition to an  optocoupler it requires a 12 V  double-pole  relay  with  mains  rated contacts and a small power  supply  for  the  optocoupler.  When the laptop...

The AVR Stick is a simple data logging device that instantiates itself as an HID keyboard and reports the voltages, along with a ‘timestamp,’ from two pins on an ATtiny85. The device uses open source firmware availabe from Objective Development (http://www.obdev.at/vusb/) called V-USB to implement the USB 1.1 standard. The code that runs the application was based on the EasyLogger example application from Objective development.

Most of the time, in a cartoon or in a movie, whenever the character experiences an “Eureka!” moment, a light bulb would just appear on the head. Well, just in case your boss thinks that you are the dimmest bulb in the office, prove him or her wrong by picking up the £10.99 Bright Idea USB Lightbulb.     Yes sir, I think you do know just which direction I am heading with this – it is the perfect desk accessory which lets the world around you know just how many brilliant thoughts you would have come up with throughout the eight hours at the desk! Located right at the end of a sturdy and flexible arm, lies the Bright Idea USB Lightbulb which happens to be a fuss-free lamp, sans switches, where it will also not come with a lampshade nor any legs. No sir, it is up to that creative mind of yours to concentrate and deliberate over grand ideas. ou will find it emit a soft and soothing blue light as long as it remains plugged into any USB port, where it will shine some reassuring illu...

Using this circuit we can convert 5V DC from the computer USB port to 12V DC and a circuit like this will find a lot of application in USB powered systems. The heart of this circuit is IC LT1618 which is a constant current, constant voltage boost converter. The IC has a wide input voltage range of 1.8 to 18V DC and output voltage can be up to 35V DC. In the circuit resistors R1, R2 sets the output voltage. Pin number 9 is the shutdown pin, less than 0.3V to this pin will shut down the IC. Pin number four is the current sense adjust pin. The current sense voltage can be reduced by applying a DC voltage to this pin. If this adjustment is not needed connect this pin to ground and you can omit components R3, R5 and Q1. Simple 12V From USB Port - 5V to 12V Converter Circuit Diagram Notes C2 and C3 must be rated at least 15V. Less than 0.3V at the shutdown pin will shutdown the IC. Output voltage is governed by the following equation R1 = R2 (  (Vout /1.263V) -1).