2 ms·

> a chip with like 4 pins Power, Ground, Data In, Data Out does the perfect architecture need more?

• dragontamer 2y ago
  A lot of devices, such as RFID, are just Power (no ground, no data). AC Power delivered by Radio provides both high-and-low voltage, which is captured by the end device. The end device can then respond over that same frequency by pulsing. ----- There's also a variety of Power+Ground / 2-wire devices on the market if you are in DC (Data shared on the Power-line), which is kind of the idea behind 4-20 (draw between 4mA to 20mA depending on remote sensor information). There's a wide variety of techniques to multiplex data "into" the power-line. If you absolutely must have a minimum number of pins, the absolute minimum is Power+Data and Ground (where Data is say... current based like 4-20mA protocol). Power stays at 24V relative to ground, while the device changes its own current based on sensors to communicate. The power-line can measure the current. ------- I know I was looking at a pulsed power / changing current protocol recently. Basically the current "pulses" based on the information it wants to send back. So its different than 4-20mA but still a similar concept (pulse-current-modulation for communication over Power+Data line vs Ground line.)