Operational Amplifiers – With a few Op-Amps and a regulated Power supply, many Instrumentation and Process control equipment can be designed. The Human Brain understands Numbers, Quantity and it regulation very well ! On the right you can see a analog controller based on opamps and discrete devices. A Heater, Fan and Motor is regulated, controlled and timed for a process.
Analog is about numbers, the circuits can be understood and designed mathematically or empirically. Designing and Building a True RMS Rectifier with Op-Amps, will help a designer digest many Op-Amp capabilities.
Things you ought to know about Op-Amps –
OpAmp part numbers from various semiconductor companies are designed for both General purpose and special applications. Some have to be cost-effective for consumer low-cost equipment, while others may be advanced in specs, closing in on an ideal Op-Amp.
- Square and Triangle Op-Amp Oscillator
- Inverting Amplifier – Op-Amp Circuits
- Non-Inverting Amplifier – Op-Amp Circuits
- Differential Amplifier – Op-Amp Circuits
- 3 Op-Amp Differential Instrumentation Amp
- Buffer or Unity Gain Op-Amp
- Two Op-Amp Differential Amplifier
Instrumentation opamps are used for accurate and low drift applications. These Op-Amps have stringent specifications and are used in the fields like Aerospace or Medical Electronics. A pre-amplifier for an FM Radio may need to be low-priced. Test Measurement needs Op-Amps which have near ideal specs in the area of measurement or application. CMOS low-power devices are used when designs are made for portable gadgets.
- Outputs cannot be Loaded beyond the drive capacities, Note Resistors and Output Load.
- Inputs draw a small bias current and will load the signal sources, compensate design.
- Op-Ams AF-RF or Switching performance study with Slew rate and Bandwidth.
- Power consumption of some Op-Amps are more and some very less, choose wisely.
- Look for Standard Pin-Outs, Price, Popularity and study Abs. Max, AC and DC Specs.
- Use Packages with multiple Op-Amps like LM324 to save board space and assembly time.
- Op-Amps and its 1% MFR resistors should have a separate supply and far from hot parts.
- Ultra Low Offset Voltage is required, when you wish to amplify a DC level of say 500uV.
- Guard rings to be used for High impedance inputs and EMI-RFI Shielding for AF Amplifiers.
- Glass epoxy PCB, clean surface, Pins and Tracks protected from Moisture and Chemicals.
- Avoid Ground Loops, Have regulated Low ripple Power supplies. Dynamic Isolation.