User manual

Active Filter Demo Board Kit User’s Guide

To implement dual supplies, it is also necessary to change the Active Filter Section

(see Figure 4-2) set-up:

• The boards’ bypass capacitors (C1 and C3) need to be removed and replaced

- Connect one set from –VS (board GND) to GND (board VDD/2)

- Connect the other set from +VS (board VDD) to GND (board VDD/2).

• If desired, R1 and C1 can be removed

• Connect the Oscilloscope as follows

- Oscilloscope signal probe to VOUT (TP1)

- Oscilloscope GND probe to VDD/2 (TP3)

FIGURE 4-2: Setting up Active Filter Section” or dual supplies.

Using dual supplies may not work well for high frequency designs. –V

will be

connected to the ground plane, instead of GND, causing greater radiation of supply

noise and more crosstalk.

4.2.2 Increased Power Supply Voltages

The total voltage across the power supplies should not exceed the op amp’s

specification (5.5V for the MCP6271). The large bypass capacitors on each board are

rated at 16V, which also limits the possible supply voltage.

If necessary, op amps with higher supply voltage can be accommodated. The boards’

bypass capacitors must be removed and replaced with other bypass capacitors with a

higher voltage rating.

Note: Do not connect the oscilloscope GND probe to board GND (TP2) when set

up for dual supplies; this may cause a ground conflict between lab

equipment.

Oscilloscope

GNDV

OUT

Do not connect

ground probe to GND

GND

OUT

GND