I am building the circuit on page 5 of this appnote:
http://focus.ti.com/lit/ug/sluu023b/sluu023b.pdf
I have not included resistors R16, R15, or R17 in my circuit because they are not necessary for my application.
Looking at the schematic I can only see one path for current to take when all of the transistors and are off and that would be from:
+VDC-->D6B-->R21-->R14-->R12-->R20-->Ground
I add those up and I get a resistance 331K but when I check the resistance of my circuit across VDC+ and VDC- I get a resistance of only 500 ohms. I'm scared to plug this thing in until I know for sure what the resistance should be. Would the PNP transistors and P-Channel FET be conducting when measuring resistance with an ohm meter?
http://focus.ti.com/lit/ug/sluu023b/sluu023b.pdf
I have not included resistors R16, R15, or R17 in my circuit because they are not necessary for my application.
Looking at the schematic I can only see one path for current to take when all of the transistors and are off and that would be from:
+VDC-->D6B-->R21-->R14-->R12-->R20-->Ground
I add those up and I get a resistance 331K but when I check the resistance of my circuit across VDC+ and VDC- I get a resistance of only 500 ohms. I'm scared to plug this thing in until I know for sure what the resistance should be. Would the PNP transistors and P-Channel FET be conducting when measuring resistance with an ohm meter?