555 EFI: Voltage level conversion

[Ludis Langens]

Don Holtz <daholtz at axionet.com> wrote:
> Since the span of the voltage range that you want to move is smaller (and
> not inverted), you can do the conversion WITHOUT using any kind of active
> stage.  However, it may be necessary to use some buffering at the input or
> output depending on the proceeding section of circuit.

Yes, that's quite right!  Why didn't someone point this out earlier?

> Try this: use a simple resistive voltage divider to reduce the span of the
> 0-5V signal to  a 0-1.666 signal.  Then use a diode level shifter with high
> impedance biasing to shift the range from 0-1.66V up to 3.333-5V.

No level shifter is required.  Use a voltage divider to 5V, instead of
GND like normal.  For example, connect a 2K resistor between the 0-5V
signal and the output node.  Then connect a 1K resistor between the
output node and 5V.  The output of this divider will be 3+1/3 to 5V.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/