R Thread Starter rainaby Joined Nov 6, 2011 9 Nov 8, 2011 #1 Can anyone please explain why totempole outputs should not be connected together what is the solution
Can anyone please explain why totempole outputs should not be connected together what is the solution
SgtWookie Joined Jul 17, 2007 22,227 Nov 8, 2011 #2 If you tie two totem-pole outputs together, they will "fight to the death" if they are set to different logic levels. You can use diodes from each output with a pull-up or pull-down resistor, depending on the logic you want. You can tie open-collector outputs together and use a pull-up resistor to create a wired AND gate.
If you tie two totem-pole outputs together, they will "fight to the death" if they are set to different logic levels. You can use diodes from each output with a pull-up or pull-down resistor, depending on the logic you want. You can tie open-collector outputs together and use a pull-up resistor to create a wired AND gate.
SgtWookie Joined Jul 17, 2007 22,227 Nov 8, 2011 #4 A pull-down resistor has one end connected to the low voltage in the circuit; in the case of TTL and CMOS, that is usually ground or Vss. A pull-up resistor has one end connected to +V, Vcc or Vdd.
A pull-down resistor has one end connected to the low voltage in the circuit; in the case of TTL and CMOS, that is usually ground or Vss. A pull-up resistor has one end connected to +V, Vcc or Vdd.