October 2011 – Electronic Circuit Diagram

Three Wire RS232 To RS485 Converter

October 28, 2011 Rust

The schematic diagram below show the circuit diagram of an RS232 to RS485 converter circuit. The EIA-485 standard, a.k.a TIA/EIA-485 or RS-485, is a physical layer standard defining the electrical properties of electronic drivers and receivers using balanced digital signal which is capable of handling multipoint systems. The ANSI Telecommunications Industry Association/Electronic Industries Alliance (TIA/EIA) is the organization who publish […]

Category: Data Communication Tags: Converter, RS-485

Analog Multiplier-Divider with 4136 Op-Amps

October 24, 2011 Rend

This unique circuit below can be used as divider and multiplier. This circuit is formed by all four sections of a 4136 . The Q1 through Q4 can be any PNP transistor, but that must matched transistors. The transistor matching determine the acurracy of the divider and multiplier circuit. Here is the schematic diagram of the circuit:

Category: Basic Function Circuits Tags: Signal Processing

30-Khz Bandwidth High Linearity Opto-Isolated Amplifier

October 13, 2011 Rend

Using optocoupler to directly transfer a linear (analog) voltage would produce a large unpredictable linearity error, which is also sensitive to temperature changes. By using frequency modulation, the total system’s linearity will depend only on the linearity of the V/F and F/V converter, which is fortunately cancel each other if we use similar devices with similar non-linearity error characteristic. A […]

Category: Data Communication Tags: Optoelectronics, Pre-Amplifier, Pulse Modulation

Sound-Activated Lamp (Relay/Switch)

October 1, 2011 Rend

This simple circuit shown int the schematic diagram actives the switch using sound. We can use this circuit for various applications, such as automatic (sound-controlled) disco light or car’s LED light show. The Q1 amplify the audio from mic. The R1 is used to adjust the peak of signal to greater than about 0.7 volts, act as sensitivity adjuster. A […]

Category: Control and Monitoring Tags: Relay, Sound Sensor

Month: October 2011

Three Wire RS232 To RS485 Converter

Analog Multiplier-Divider with 4136 Op-Amps

30-Khz Bandwidth High Linearity Opto-Isolated Amplifier

Sound-Activated Lamp (Relay/Switch)