Optically isolated anti-jamming technology

In the actual electronic circuit system, inevitably there are various interfering signals, anti-interference ability is poor if the circuit will cause the measurement, control accuracy decreased, resulting in malfunction, resulting in devastating consequences. Therefore, if the hardware using some design techniques,lcd module destroy the interference signal into the control system approach, which can effectively improve anti-jamming capability. Facts have proved that the use of isolation technology is a simple and effective method. Isolation technology is the destruction of the "land" means interference immunity method commonly used in optical coupling device hardware electrically → light → electrical isolation, he can effectively destroy the source of interference to enter, to achieve reliable signal isolation, and easy to form the kind of functional status.
Optical coupling devices are the light-emitting device (such as light emitting diode) and a photosensitive device (such as a phototransistor) assembled together to form electrically coupled achieved through light - light and light - electricity conversion device. Figure 1 shows the common optocoupler transistor schematic.
When an electrical signal fed to the optocoupler input, light-emitting diodes by the current and light, lcm module after light generated by the photosensitive element current, CE conduction; when no signal is input, the LED is not lit, phototransistor deadline, CE unreasonable. For digital, when the input is low level "0", the photosensitive transistor off, the output is high level "1"; when the input is high level "1", the phototransistor saturated conduction, the output is low "0." If a lead base may meet the temperature compensation, detecting modulation requirements. This optocoupler performance is better, cheaper, and thus widely used.