Texas Instruments THS4012 - Manual (Page 11)

THS4012 EVM Noninverting Operation
1-5 General
Any of the resistors on the EVM board can be replaced with a resistor of a
different value; however, care must be taken because the surface-mount
solder pads on the board are somewhat fragile and will not survive many
desoldering/soldering operations.
External factors can significantly affect the effective gain of the EVM. For
example, connecting test equipment with 50-
Ω
input impedance to the EVM
output will divide the output signal level by a factor of 2 (assuming the output
isolation resistor on the EVM board remains 50
Ω
). Similar effects can occur
at the input, depending upon how the input signal sources are configured. The
gain equations given above assume no signal loss in either the input or the
output.
Frequency compensation capacitors C3 and C6 may need to be installed to
improve stability at lower gains. The appropriate value depends on the
particular application.
The EVM circuit board is an excellent example of proper board layout for
high-speed amplifier designs and can be used as a guide for user application
board layouts.