A comparative analysis of implementations of an optical front–end with variable transimpedance in two different BiCMOS technologies is given. The variable-gain current amplifier within the optical front–end is designed by using a modified balanced type of the bipolar junction transistors translinear loop. The useful measured transimpedance dynamic range of the proposed optical front–end is 17.5 times larger in the 0.6-µm BiCMOS silicon technology than that in the 0.35-µm BiCMOS silicon-germanium technology because of the much better stability of the silicon implementation.