Figure 8-1 shows an overview of the internal structure of the BUF802. The internal schematic
of the BUF802 can be divided into the following 3 parts:
- Input Stage, which
consists of a low noise JFET and its biasing circuitry. The Input Stage can be
configured in two modes, BF Mode and CL Mode. Choosing one of the
two modes affects the circuit operation of the Input Stage. The Clamp and Output
Stage operation are unaffected by the mode selection. Section 8.4 describes the two modes
in greater detail.
- Clamp Stage, which
provides the following functions:
- Protects the input of the
BUF802 against large input signal transients through diode clamps to
VS- and CLH respectively.
- Ensures the output
voltage of the BUF802 does not exceed the voltage at the CLH and
CLL.
- Output Stage, which tracks
the JFET source voltage and is optimized to drive a 50 Ω and 100 Ω load while
maintaining signal fidelity.