I want to control the FP6293 ICs enable pin with the Atmega 328p pin PD5 (configured as digital out). The EN pin (active high) on the IC is rated at max 6V with a minimum HIGH voltage of 0.96V. As the microcontrollers IO will be setup as an output, when the output is high current will flow to the FP6293 right?

Do I have to use some sort of series resistor between the IO and the EN pin?

Or is it ok to just connect the two pin together and have a pull-down resistor?

link to FP6293 datasheet: https://datasheet.lcsc.com/szlcsc/Feeling-Tech-FP6293XR-G1_C83576.pdf

  • \$\begingroup\$ There will be no high current since the EN is a high impedance input. You can simply connect both directly. Use Pull down to not let it float. \$\endgroup\$ – stowoda Jan 16 at 11:16
  • \$\begingroup\$ Ok. How did you find this out? The high impedance. \$\endgroup\$ – user3635319 Jan 16 at 11:36
  • \$\begingroup\$ On page 1 you have a typical application circuit. There, EN is directly tied to Vin (which is apparently a low impedance source). \$\endgroup\$ – stowoda Jan 16 at 11:40
  • \$\begingroup\$ Got it. Should have EN been tied to Vin with a resistor the it would've been a high impedance pin? \$\endgroup\$ – user3635319 Jan 16 at 11:45
  • \$\begingroup\$ Not necessarily. Being tied to Vin only shows that no significant amount of current will flow into that input. Besides, it is not unusual that this kind of input (control input) is high Z. You dont want to waste energy just for a control signal. Probably it goes directly to a MOSFET gate. \$\endgroup\$ – stowoda Jan 16 at 12:50

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