MCP6271 datasheet(16/34 Pages) MICROCHIP

16 / 34 page

MCP6271/2/3/4/5

DS21810D-page 16

 2004 Microchip Technology Inc.

4.8.3.6

Second-Order Sallen-Key with an

Extra Pole-Zero Pair

Figure 4-14 is a second-order Sallen-Key low-pass

filter with Chip Select. Use the Filterlab® software from

Microchip to determine the R and C values for

op amp A’s second-order filter. Op amp B can be used

to add a pole-zero pair using C3, R5 and R6.

FIGURE 4-14:

Second-Order Sallen-Key

Low-Pass Filter with an Extra Pole-Zero Pair and

Chip Select.

4.8.3.7

Capacitorless Second-Order

Low-Pass filter with Chip Select

The low-pass filter shown in Figure 4-15 does not

require external capacitors and uses only three exter-

nal resistors; the op amp’s GBWP sets the corner fre-

quency. R1 and R2 are used to set the circuit gain. R3

is used to set the Q. To avoid gain-peaking in the

frequency response, Q needs to be low (lower values

need to be selected for R3). Note that the amplifier

bandwidth

varies

greatly

over

temperature

and

process. This configuration, however, provides a low-

cost solution for applications with high bandwidth

requirements.

FIGURE 4-15:

Capacitorless Second-Order

Low-Pass Filter with Chip Select.

VIN

VOUT

MCP6275

VREF

VIN

VOUT

MCP6275

MCP6271 Datasheet(PDF) 16 Page - Microchip Technology

MCP6271 Datasheet(HTML) 16 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

Datasheet Download

Link URL