Amplifier and comparator chips are board-level components for amplifying voltage, current, or power. There are several basic types of amplifier and comparator chips.

Differential amplifier chips are designed to amplify a small difference between two signal levels and ignore any common level shared between them.

Instrumentation amplifier chips are precision amplifier circuits with both high-impedance differential inputs and high common-mode rejection. The differential gain can be adjusted by changing the value of a single resistor.

Logarithmic amplifier chips (log amp chips) produce an output voltage that is directly proportional to the logarithm of the input voltage. Operational amplifier chips (op amp chips) are general-purpose, closed loop devices used to implement linear functions. They compare two incoming signals and release a third that is an amplified measure of the difference between the two.

Power operational amplifier (POA) chips are used to increase the power of low-level signals in applications that drive low impedances or reactive loads. Pulse width modulated (PWM) amplifier chips generate a current that switches between high and low output levels.

Sample-and-hold amplifier chips freeze analog voltage instantly. During this process the HOLD command is issued and analog voltage is available for an extended period. Specialized amplifier and comparator chips are also available.

Performance Specifications

Amplifier and comparator chips differ in terms of performance specifications and available features.

Video Credit: American Microsemiconductor, Inc. / CC BY-SA 4.0

Specifications for differential amplifier chips include:

• Bandwidth

• Gain, minimum gain

• Supply voltage

• Supply current

• Offset voltage

• Slew rate

• Harmonic distortion (second and third harmonics)

Specifications for instrumentation amplifier chips include:

• Input common-mode voltage range to negative rail

• Rail to rail (input or output)

• Gain, minimum stable closed loop gain

• Maximum supply current

• Maximum voltage offset

• Typical common mode rejection ratio

• Typical power supply rejection ratio

• Maximum input bias current

• Typical unity gain bandwidth

• Typical slew rate

• Input voltage noise

• Input current noise

Specifications for power operational amplifier chips include:

• Supply voltage range

• Internal power dissipation

• Quiescent current

• Power bandwidth

Available Features

Features for differential amplifier chips include:

• Number of leads

• Package type

• Power-down options

Features for power operational amplifier and comparator chips include:

• On-chip electrostatic discharge (ESD) protection

• Rail-to-rail outputs

• Embedded current limits

Parameters for PWM amplifier chips include output current, input offset voltage, supply voltage range, internal power dissipation, and quiescent current. Specialized amplifier and comparator chips also differ in terms of specifications and features.

Standards

SMD 5962-90955 - Microcircuit, linear, wideband logarithmic amplifier, monolithic silicone.

SMD 5962-92234 - Microcircuit, digital, fast cmos, 8-bit identity comparator with chip enable, ttl compatible inputs and limited output voltage swing, monolithic silicon.
SMD 5962-08214 - Microcircuit, linear, dual low offset, matched, operational amplifier, multi-chip silicon.
SMD 5962-93003 - Microcircuit, linear, dual operational amplifier with dual comparators and voltage reference, monolithic silicon.
DESC-DWG-85089 - Microcircuits, linear, wideband power operational amplifier, thickfilm hybrid.
MIL-M-38510/119 - Microcircuits, linear, low power, low noise, bi-fet operational amplifiers, monolithic silicon.

Image Credits:

Texas Instruments High-Performance Analog | ROHM Semiconductor USA, LLC | MAZeT GmbH