Free Circuit Diagram

RJ45 is used to connect Ethernet port on your computer. There are two configuration: straight and cross. Straight RJ45 cables should be used to connect between computer and device such as switch or hub, and cross RJ45 cables should be used in computer-to-computer connection.  Some hub or switch has the capability to detect the cable [...]

This pin diagram will be  useful when viewing these connectors. Sometimes you hold a soldering iron to the back of the connector, and you don’t remember the numbering of the pin. Here is the pin diagram for your reference: The number of each pins are actually  stamped on both sides of any D-type [...]

The configuration in the circuit diagram below can be used when a slow rise time of the output voltage is required. We can find the rise time with following formula: ton= CVoR 0.45 Capacitor C is discharged when the switch position is ON and this will maintain the voltage [...]

Bubba oscillator is another example of phase shift oscillator. The Bubba oscillator takes the advantage of quad op-amp package to get 45 degree phase shift for each section. The result is excellent d(phase)/d(t) to get very low frequency drift. Here is the schematic diagram of the circuit: Each RC section give 45 degree [...]

RS485 interface gives some more benefits compared to RS232: simplicity and the robustness for long distance transfer. RS485 is simpler because it uses only two wire (or a single pair) to carry out the data in bidirectional manner, using RS232, we need 3 wires at minimum to carry the data bidirectionally. RS485 cable length can [...]

Many new computers now only has USB port, and this serial to USB adapter might be the only help for old devices that provides only RS232/COM Port. This serial adapter uses FT232 USB-RS232  converter IC from FTDI (Future Technology Devices International).  The main features of this USB serial adapter chip are: 384 [...]