
120 Analog Circuits Cookbook
Stage 1 involves bootstrapping the BClOffs collector (Figure 4.22), which
is seen to be very effective indeed in shortening the input time-constant,
though there is still a shortfall in low frequency gain. The all-important
point to note is that the bootstrapping of the collector only works because
there is a separate stage following the emitter follower, providing current
gain. The collector cannot be bootstrapped from the input emitter follower's
own emitter even though such an arrangement was seriously proposed in
Wireless World by a well-known writer on electronics, whose name shall
remain unstated to spare