MCP6476T datasheet(15/46 Pages) MICROCHIP

15 / 46 page

 2020-2021 Microchip Technology Inc.

DS20006419B-page 15

MCP6476/6R/6U/7/9

4.0

APPLICATION INFORMATION

The MCP6476/6R/6U/7/9 operational amplifier is unity

gain stable and suitable for a wide range of general

purpose applications.

4.1

Rail-to-Rail Input

4.1.1

PHASE REVERSAL

The MCP6476/6R/6U/7/9 op amp is designed to

prevent phase reversal when the input pins exceed the

supply voltages. Figure 2-37 shows the input voltage

exceeding the supply voltage with no phase reversal.

4.1.2

INPUT VOLTAGE LIMITS

In order to prevent damage and/or improper operation

of the amplifier, the circuit must limit the voltages at the

input pins (see Section 1.1 “Absolute Maximum

Ratings†”).

The Electrostatic Discharge (ESD) protection on the

inputs can be depicted as shown in Figure 4-1. This

structure was chosen to protect the input transistors

against many, but not all, overvoltage conditions, and

to minimize the Input Bias (IB) current.

FIGURE 4-1:

Simplified Analog Input ESD

Structures.

The input ESD diodes clamp the inputs when they try

to go more than one diode drop below VSS. They also

clamp any voltages that go well above VDD; their

breakdown voltage is high enough to allow normal

operation. At 0.5V above VDD or below VSS, the input

currents are typically less than 5 mA. Very fast ESD

events that meet the specification are limited so that

damage does not occur.

4.1.3

INPUT CURRENT LIMITS

In order to prevent damage and/or improper operation

of the amplifier, the circuit must limit the currents into

the input pins (see Section 1.1 “Absolute Maximum

Ratings†”).

Figure 4-2 shows one approach to protecting these

inputs. The resistors, R1 and R2, limit the possible

currents in or out of the input pins through the ESD

diodes to either VDD or VSS.

FIGURE 4-2:

Protecting the Analog Inputs.

-IN

+IN

VSS

VDD

OUT

VDD

VSS

–

VDD

min(R1,R2)>

VSS –min(V1, V2)

5mA

MCP6476

VOUT

min(R1,R2)>

max(V1,V2)–VDD

5mA

MCP6476T Scheda tecnica(PDF) 15 Page - Microchip Technology

MCP6476T Scheda tecnica(HTML) 15 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 43 44 45 46

Scheda tecnica Scarica

Link URL