THS4303: Positive signal amplification

Hello Vlad,

The THS4303 may be used in single-supply or split-supply configurations.  The SPICE models typically showcase split supply, with the option to set the negative supply to GND.

Regarding your application, you are correct in reasoning you will need some DC offset to handle a 0V input signal on single-supply.  The Electrical Characteristics subsections denoted "Input Characteristics" and "Output Characteristics" describe the input/output voltage limitations based on supply configuration and temperature range.  For example, on a 5V single supply configured THS4303, the common mode input range over -40C to 85C range is 1.2V - 3.8V.  Similarly, the output range is 1.2V - 3.8V for the same supply and temperature conditions.

Knowing this, for your input signal values, you would need to bias the input to a DC value of 1.2V or greater.  The resulting waveform would operate between 1.2V and 3.2V, staying within the recommended operating range.  Exceeded either the minimum or maximum value (1.2V & 3.8V respectively) will cause distortion and unwanted behavior.

For the sake of margin and simplicity, a 1.5V DC bias would work as well, resulting in your original signal operating from 1.5V to 3.5V.  On a 3V single supply (the minimum recommended for the THS4303), your ranges are even smaller.  With your signal pk-pk voltage, I would recommend the expected 5V single supply.

If you absolutely must have 0V input without any bias circuitry, you would need to use an unbalanced split supply, such as Vs- = -1.5V & Vs+ = 3.5V.  Your range of operation would be from -0.3V to 2.3V, which allows your original 0V to 2V input signal.  

Best,

Alec