Spehro's solution can get you where you want to go. Note you will need an
opamp that can swing as high as 10 volts out so it's supply must be
considered.  And it needs to swing down to .3 volts so if you are working
with a single supply setup, this too needs to be considered.

And finally, if you wanted to, you could ground the positive input and add
a summing resistor from a negative voltage to the negative input to produce
the requisite offset voltage. But this would need a negative supply where
Spehro's solution can be done with only a single supply.

You asked how to approach the design.  y = mx + b is the answer. m is the
slope.  The slope is your output span divided by your input span. Here it
equals -1.94 so that's what set's the ratio of the resistors in Spehro's
circuit.

To get 'b' from the formula, you need to remember the gain is different for
the non-inverting input.

The offset as shown is applied to the positive input and the formula for
gain for the positive input is the ratio of the feedback resistor to the
input resistor plus 1.  So here the gain of the offset channel is 2.94.
With zero volts in and you want 10 volts out, and your gain is 2.94, then
you need a voltage that = 10/2.94 = 3.402 volts.

Hope this helps.
Tom

At 04:34 PM 1/22/04 -0500, Spehro wrote:
>At 12:58 PM 1/22/2004 -0800, you wrote:
>>I need to convert a 0V to +5V DC signal to a +0.3V to +10V signal.
>>
>>Here comes the tricky part, When the signal is +5V the output needs to be
>>+0.3V. When the signal is 0V I need the output to be +10V. I am not sure
>>how to approach this type of circuit, any ideas would be greatly
appreciated.
>
>Just use an op-amp as follows:
>
>                                   1.94 * R
>                                     ___
>                                 +--|___|---+
>                                 |          |
>                   0~5V   R      |          |
>                           ___   |  |\|     |     10~0.3V out
>                    o-----|___|--+--|-\     |
>                                    |  >----+----------o
>                              +-----|+/
>                              |     |/|
>                              |
>                              |
>                              |
>                              |
>                              |
>
>                           3.402V reference

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