Archive for the ‘USB Circuits’ Category

12Volt from USB port

12 volt DC Power Supply from USB port The circuit given below infact is a 5 volt to 12 volt converter. It uses the 5 Volts from USB port and converts it to 12 volts DC with the help of IC LT1618. Description : 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…

Read More

USB sound card

Description. Designing and building a USB sound card is no longer a head ache because we have got the PCM 2702 integrated circuit from Texas Instruments. The PCM2702 is an integrated 16 bit digital to analog converter that has two digital to analog output channels. The integrated interface controller of PCM2702 is compliant to the USB 1.0 standards. The IC can handle sampling rates of 48 KHz, 44.1 KHz and 32 KHz. The IC also has a number of useful features like on-chip clock generator, digital attenuator, play back flag, suspend flag, zero flag, mute function etc. The most interesting…

Read More

USB LED Lamp circuit.

USB Lamp Circuit Description. Here is a simple USB powered lamp that can be used to light your desktop during power failures. The circuit operates from the 5 Volt available from the USB port.The 5V from the USB port is passed through current limiting resistor R2 and transistor Q1. The base of transistor Q1 is grounded via R1 which provides a constant bias voltage for Q1 together with D2.The diode D1 prevents the reverse flow of current from battery.C1 is used as a noise filter.Two white LED’s are used here for the lamp, you can also use a 2 V…

Read More