Proceed with this design using the techniques
described in the Design for Wideband Differential Transimpedance DAC
Output:
- Generate the bipolar balanced supplies using the LM27662.
- Set the THS4552 output common-mode voltage at midsupply by grounding the VOCM pin.
- Control the input pin operating voltage by sinking the center current out of
the DAC to the –2.5 V supply with precision 402 Ω resistors.
- Set the gain for the complementary current output signal from the DAC by
selecting the feedback resistor to be 750 Ω. Set this resistor to keep the
resulting output swing to be less than the available 9 VPP
differential swing.
- Control the bandwidth in this differential transimpedance stage to 88 kHz using
the 2.4 nF feedback capacitor on each side.
- Increase the high-frequency noise gain to 17.7 V/V by adding a differential input capacitor of 20 nF.
- Isolate these feedback capacitors with a series 4.4 Ω resistor in series with
the feedback capacitors.