MCP6H94-ESLASHST datasheet(20/42 Pages) MICROCHIP

20 / 42 page

MCP6H91/2/4

DS25138B-page 20

 2012 Microchip Technology Inc.

4.7.2

ACTIVE FULL-WAVE RECTIFIER

The MCP6H91/2/4 family of amplifiers can be used in

applications such as an active full-wave rectifier, as

shown in Figure 4-9. The amplifier and feedback loops

in this active voltage rectifier circuit eliminate the diode

drop problem that exists in a passive voltage rectifier.

This circuit behaves as a voltage follower (the output

follows the input) as long as the input signal is more

positive than the reference voltage. If the input signal is

more negative than the reference voltage, however, the

circuit behaves as an inverting amplifier with a

Gain = -1V/V. Therefore, the output voltage will always

be above the reference voltage, regardless of the input

signal. The reference voltage (VREF) is supplied by a

low-impedance source. In single-supply applications,

VREF is typically VDD/2.

FIGURE 4-9:

Active Full-Wave Rectifier.

4.7.3

LOSSY NON-INVERTING

INTEGRATOR

The non-inverting integrator shown in Figure 4-10 is

easy to build. It saves one op amp over the typical

Miller integrator plus inverting amplifier configuration.

The phase accuracy of this integrator depends on the

matching of the input and feedback resistor-capacitor

time constants. RF makes this a lossy integrator (it has

finite gain at DC), and makes this integrator stable by

itself. To ensure proper operation, the op amp Common

mode input voltage must be kept within the allowed

range.

FIGURE 4-10:

Non-Inverting Integrator.

–

VIN

VOUT

VREF

R/2

Op Amp A

Op Amp B

VREF

time

Input

Output

1/2

MCP6H92

1/2

MCP6H92

VIN

VOUT

OUT

-------------

1C1



--------------------

R

1C1 1

------





-------------------------------------------







MCP6H91



1C1

2||RF

C

MCP6H94-E/ST Datasheet(PDF) 20 Page - Microchip Technology

MCP6H94-E/ST Datasheet(HTML) 20 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

Datasheet Download

Link URL