The electrical parameters of AMP1 are shown in the Electri-
cal Characteristics section.
17.0 Stand-Alone Amplifier
A stand-alone Amplifier, AMP1, is provided on Port B. It
supports rail-to-rail inputs and outputs, and operates over
the entire VCC and temperature range. This amplifier is in
addition to the programmable gain amplifier in the A/D Con-
verter. It is an alternate function on Port B.
17.1 BLOCK DIAGRAM
It is enabled/disabled by the ENAMP1 bit in the ADGAIN
register described in the A/D Converter section. The normal
port B3–B5 pins should be configured in their high Z state
when using AMP1. It is disabled after Reset. The circuit will
only draw current when it’s enabled. When disabled, the
current drawn is extremely low.
20006359
FIGURE 30. Amplifier1 Block Diagram
When using the HALT mode of the device, AMP1 will draw
current unless it is disabled by software. Therefore, for mini-
mal current in HALT mode, AMP1 should be disabled prior to
entering HALT.
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