Kj. Delangen et al., A 1-GHZ BIPOLAR CLASS-AB OPERATIONAL-AMPLIFIER WITH MULTIPATH NESTED MILLER COMPENSATION FOR 76-DB GAIN, IEEE journal of solid-state circuits, 32(4), 1997, pp. 488-498
A 1-GHz operational amplifier with a gain of 76 dB while driving a 50-
Omega load is presented. The equivalent input noise voltage is as low
as 1.2 nV/root Hz. This combination of extremely high bandwidth, high
gain, and low noise is the result of a three-stage all-n-p-n topology
combined with a multipath nested Miller compensation, Using 10-GHz f(T
) n-p-n transistors, the realizable bandwidth could be of the order of
2-3 GHz. However, bond-wire inductances restrict the useful bandwidth
to 1 GHz. The amplifier occupies an active area of 0.26 mm(2) and has
been realized in the bipolar part of a 1-mu m BiCMOS process.