Does the field of the single chip and dc motors need to be isolated?
Your power supply is not public. If it is, it is best to isolate it with a big power. I want to know why the top nine people don't explain it.
You use a 5 v to 5 v isolation power supply, the output lead Angle in to add a light lotus root to isolate, but the isolation to drive the relay, do you want to come with triode amplifier in the current, or drive the relay, light lotus root you can use the P521 (or one of TLP521-2) to isolate, light lotus root 521 lead Angle is: 1, 2, Angle of internal are light-emitting diodes (leds), 1 Angle of the positive; 3, 4 is the C of the internal triode, the Angle of E.
If you're using the same power source, what's the difference? If you use more than 12V, you'd better be independent. Or you can use a stabilizer to power a single chip, and then you run out. If you are a direct drive motor, you'd better be able to find a way to make a connection. If it's about 24V, you're going to use the relay plus the MOS tube, and you'd better not be in total,
Optical coupler's main advantage is: to signal transmissions, the input and output electrical isolation was fully implemented, can not influence the output signal of the input, strong anti-interference ability, stable work, non-contact, service life is long, high transmission efficiency. Optical coupler is developed in the 70 s to produce new type of device, is now widely used in electrical insulation, level conversion, interstage coupling, drive circuit, switch, chopper, multivibrator circuit, signal isolation, interstage isolation, pulse amplification circuit, digital meters, remote signal transmission, pulse amplification, solid state relay (SSR), instruments and meters, communication equipment and microcomputer interface. In the monolithic switch power supply, linear optical coupler can constitute light coupling feedback circuit, by adjusting the control side to change the duty cycle, current to achieve precision voltage regulator.
Need to be isolated, normally use photoelectric segregation. The optical coupler consists of three parts: the emission of light, the reception of light and the amplification of the signal. Input signal drive light-emitting diodes (leds), to a certain wavelength of light, by the light detector and photocurrent generation, again after further amplification output. This completes the conversion of electricity - light - electricity, which ACTS as input, output, and isolation. It is separated by the input and output of optical couplers, and the transmission of electrical signals is unidirectional, so it has good electrical insulation ability and anti-interference ability. The input side of the optical coupler is a low resistance component of the current type of work, and therefore has a strong co-mode inhibition capability. Therefore, it can greatly enhance the signal-to-noise ratio as the terminal isolation element in the long-term transmission information. In computer digital communication and real-time control as the interface device for signal isolation, the reliability of computer work can be greatly increased.
