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Im looking to control a PT2264 RF transmitter module from an arduino so that I can transmit to different receivers. To do this I need to supply either +12v or 0v to the various address pins of the PT2264 IC depending on which receiver I am addressing. The code will be done in a way so that both mosfets are not saturated at the same time (ie avoid a dead short). I believe the current draw from the PT2262 to be minimal. My proposed solution is this:

circuit diagram

PT2262 datasheet: (http://pdf1.alldatasheet.com/datasheet-pdf/view/35122/PTC/PT2262.html)

Would this work in its current form?

Could both mosfets be switched by a single arduino pin?

Many thanks for any feedback.

Joe

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  • \$\begingroup\$ Your image is terrible, you really think we can decipher a 150x100 pixel blob? \$\endgroup\$
    – KyranF
    Aug 17, 2015 at 23:19
  • \$\begingroup\$ For such a simple circuit you can use this site's integrated circuit drawing program, look for the little schematic/circuit symbol while editing/writing your question \$\endgroup\$
    – KyranF
    Aug 17, 2015 at 23:21
  • \$\begingroup\$ That circuit puts 12V against the output, which 1) you don't want, and 2) won't work. \$\endgroup\$ Aug 17, 2015 at 23:27
  • \$\begingroup\$ Better quality photo now uploaded - it shows up for me as full quality. I do not have access to a computer at presented so doing the best I can on a phone therefore I cant use the circuit drawing program. \$\endgroup\$
    – joeka101
    Aug 17, 2015 at 23:27
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    \$\begingroup\$ Don't use two FETs. Just use the N-channel to pull low and a simple pull-up resistor to pull high. Probably 10K. \$\endgroup\$
    – DoxyLover
    Aug 17, 2015 at 23:30

2 Answers 2

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A push pull set up like you show is excessive, and could result in a near short if both outputs are active at the same time. A single npn or n channel mosfet, with a pull up to 12V would work. Essentially replacing the p channel mosfet with a 10k resistor is all you need.

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Loose the P channel and associated resistor. Replace it with a 10k pullup. Good to go! Just remember that it is inverting.

schematic

simulate this circuit – Schematic created using CircuitLab

Transistor selection constraints (leave some room):

  • Vgs,on < 3.3V
  • Vds,max > 12V
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  • \$\begingroup\$ Hmm... (checks time stamp) jinx! \$\endgroup\$
    – Passerby
    Aug 17, 2015 at 23:50
  • \$\begingroup\$ Also your missing the node below the 10k above the source that goes to the IC. \$\endgroup\$
    – Passerby
    Aug 17, 2015 at 23:51
  • \$\begingroup\$ @Passerby I noticed that too! I thought it was funny that we even picked the same value. I'll clarify that thank you. \$\endgroup\$ Aug 17, 2015 at 23:52
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    \$\begingroup\$ @HoustonFortney can you add to your answer saying that the gate drive voltage for this device needs to work with only 3.3V (From the ATMEGA Mega), meaning whatever N-channel FET is chosen, the Vgs_th should be definitely < 2.5V to ensure a decent on/off at 3.3V \$\endgroup\$
    – KyranF
    Aug 18, 2015 at 0:23
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    \$\begingroup\$ The Arduino Mega runs at 5V. \$\endgroup\$ Aug 18, 2015 at 0:30

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