I'm working with 0 to 5 volts. I was wondering if there was any way, preferably with transistors, less preferably with ICs, to "flip flop" the 5 voltage magnitude across a single wire. For example, current would first move from left to right, then 10ms later from right to left, then 10 ms later from left to right, etc.

I would prefer to keep the voltage at 5 volts in this case. I'm wondering if this would require me to add a negative supply (-5V min). If this is necessary, can you please explain how i would go about flipping the current in this later case?

I have two possible applications involving a grounded and ungrounded load of approximately 100 kOhm.

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    \$\begingroup\$ Adding a circuit diagram (no matter how rough) would help. \$\endgroup\$
    – Hari
    Mar 9, 2017 at 1:48
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    \$\begingroup\$ You cannot, by definition, "keep the current at 5 volts". And is there anything else attached to the wire, or are you only diriving the wire? Please fill us in on exactly what you are trying to do. \$\endgroup\$ Mar 9, 2017 at 4:46
  • \$\begingroup\$ Technically i have two possible applications. One is an ungrounded load the other is a grounded load. Both are 100 kOhm resistors, equivalently... This resistance may drop in a future development but currently it's skin resistance. (I mispoke there about current being at 5 Volts). When I try to make an H bridge using NPNs, the base current runs backwards into the IC that generated it. Currently looking into MOSFETs. Would adding an impedance from the IC to the base solve my problem? I tried some resistors but maybe they were too large. \$\endgroup\$ Mar 9, 2017 at 5:03
  • \$\begingroup\$ FYI there's a schematic tool for the site which is much preferred over hand-drawn schematics. Hit Ctrl-M while editing to open it. \$\endgroup\$
    – Null
    Mar 9, 2017 at 17:33
  • \$\begingroup\$ Thanks. I actually was able to test this circuit just now. So I'm going to accept Tony's answer. \$\endgroup\$ Mar 9, 2017 at 17:40

1 Answer 1


Dual drivers configured to make a full bridge. Avail in MOSFET IC's or discrete designs and depends on current.

This is for 2 wires to ungrounded load .

But if you only have a single wire then you need a bipolar supply.

Pls. Define load.


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