Using the THS4281 for high side current sensing


I'm using a THS4281 to make a general purpose High-Side current
sensor. I'm just building this on a small PCB so I can use it for
measurements. I've already successfully tested this circuit (see link
below) to measure capacitor charging pulses in a current source. The
resistor values aren't the actual values used, they will change based
on the circuit I'm using it in to measure.

http://i33.tinypic.com/6puk4l.png

Here is a schematic EDN on what I'm doing.

http://i37.tinypic.com/29ndu9s.png

My question is they show one opamp input biased at ½ Vcc in the
THS4281. See this from the THS4281 data ***.

http://i38.tinypic.com/s30cxy.png

Is this necessary the opamp is a RR in and out?

This is the layout not routed yet.

http://i37.tinypic.com/2rgyvza.png

J2 to J7 will have wires soldered so I can just plug it into a
breadboard or circuit for measuring.

Data ***

http://focus.ti.com/lit/ds/symlink/ths4281.pdf

Thanks
.

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