Page 90 - The Art and Science of Analog Circuit Design

Steve Roach

Cain is 0.91
Bandwidth is 1.1 GHz

Parasitic resonances

0 • 1
10KHz 1.0MHz 100MHz lOCHz

Frequency

1.0

Trise = 360ps

I —I--.
Os 1.0ns 2.0ns 3.0ns
Time

Figure 7-6,
proximate linear model of the BF996S is shown in Figure 7-11. The The magnitude and
BF996S comes in a SOT-143 surface-mount package, with parasitics, as step responses of
shown in Figure 7-6. the simple source
Figure 7-12 shows the frequency and step responses of the boot- follower.
strapped source follower. The bootstrapping network is AC coupled, so
Buffer

~XJ
Drain
v ~f- Figure 7-9,
v » . — -
shift
10 The bootstrapped
Gate | £.
out P re-amp source follower.
Source I Driving the drain
V 7
with the source
2pF ||10KO
f voltage increases
IN f ) bias and stabilizes
the gain.

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