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Bandpass Filter Single Opamp - A band pass filter passes a range of frequencies while rejecting frequencies outside  upper and lower limits of  passband. The range of frequencies to be passed is called  passband and extends from a point below  center frequency to a point above  center frequency where  output voltage falls about 70% of  output voltage at  center frequency. (added 6/06)

Basic Op Amp Model - One of the challenges of simulating opamp circuits is modeling the op amp itself. How is that accomplished? There's a couple of ways. You can create a circuit of many transistors, resistors and caps that closely replicate the internals of an op amp...(spice design added 02/09)

Basic Op Amp Theory & Practice Apex-AN31 - Apex App Note (added 08/08/08)

Basic op-amp circuits - (electronic circuit added 1/07)

Bias Tee - (electronic added 6/07)

Biasing & Decoupling Op Amps in Single Supply Applications - AN-581 Analog Devices Application Notes  (app note added 6/06)

Biasing Op-Amps into Class A - (electronic circuit added 4/05)

Bootstrapped IC Substrate Lowers Distortion in JFET Op Amps - AN-232 Analog Devices Application Notes  (app note added 6/06)

Bootstrapping Allows Single Rail OpAmp to Provide 0V Output - 02/06/03 EDN-Design Ideas: Many single-supply-powered applications require amplifier-output swings within 1 mV—or even submillivolts—of ground. Amplifier-output-saturation limitations normally preclude such operation. Figure 1's power-supply bootstrapping scheme achieves  desired characteristics with minimal parts count....   Although you can obtain universal, resistor-programmable switched-capacitor filters that are configurable as notch filters, most cannot operate at bandwidths higher than 100 kHz. Furr,  typically 16to 20-pin packages do not include a continuous-time, antialiasing filter to prevent spurious signals from appearing at  output.....(design idea added 12/04)

Bridging Line Amplifier  - (diagram added 6/03)

Circuit Forms Industrial Grade Digital Potentiometer - 09/20/01 EDN-Design Ideas: Both ac and dc motors in modern industrial systems often receive their control from PLCs (programmable-logic controllers)in a control room safely away from the process. If an operator must manually set the motor speed while observing the process, the component of choice is usually an industrial-grade potentiometer.....(design idea added 1/05)

Circuit Provides Inverting/Noninverting Gain - 11/09/95 EDN-Design Ideas: (design idea added 4/02)

Circuit Provides Linear I To V Conversion - 01/18/96 EDN-Design Ideas: The circuit in Figure 1 provides a 4to 20-mA voltage-to-current conversion for noise-immune data transmission in industrial data-acquisition systems. The circuit supplies two voltages to the inverting input of the control amplifier IC1A. The first voltage, from the follower IC1B, introduces an offset in the transfer function of the circuit.....(design idea added 11/05)

Class A JFET Opamp Circuit - First Generation design... that means it is not our latest design.  (circuit design added 08/08/08)

CLC730013eb 8-Pin Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730024eb Quad Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730027eb 8-Pin Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730031eb Quad Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730036eb 8-Pin Dual Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730038eb 8-Pin Dual Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730068eb SOT23-5 Op Amp Eval.Board - National Semiconductor Application Note  (app note added 2/06)

CLC730074eb Triple Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730075eb Triple Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730077eb 8-Pin Op Amp Evaluation Boards - National Semiconductor Application Note  (app note added 2/06)

CLC730114eb 8-Pin Lead-Less-Package Dual Op Amp Evaluation Board - National Semiconductor Application Note  (app note added 2/06)

CLC730121eb: 8-Pin Thermally Enhanced SOIC Psop Dual Op Amp Evaluation Board - National Semiconductor Application Note  (app note added 2/06)

CLC730123eb: 8-Pin MSOP Dual Op Amp Evaluation Board - National Semiconductor Application Note  (app note added 2/06)

CLC730216 Single High Speed Op Amp Evaluation Boards    SOIC & SOT - National Semiconductor Application Note  (app note added 2/06)

CLC730227 Single High Speed Op Amp Evaluation Boards    SOIC & SOT - National Semiconductor Application Note  (app note added 2/06)

CLC730231 Quad High Speed SOIC Op Amp Evaluation Board - National Semiconductor Application Note  (app note added 2/06)

C-Load Tm Op Amps Conquer Instabilities - DN107)  Design Notes (Linear Technology) (app note added 1/06)

C-Load Tm Op Amps Tame Instabilities - DN83  Design Notes (Linear Technology) (app note added 1/06)

CMOS Multiplying DACs & Op Amps Combine to Build Programmable Gain Amplifier, AN-320B - AN-320B Analog Devices Application Notes  (app note added 6/06)

Common-Mode Rejection - While real op amps do a fantastic job of rejecting voltages common to both inputs, it's not perfect. A small output results from a change in input common-mode voltage. What causes this output? Due to mismatching in the transistors and resistors of the input stage, the common-mode voltage produces a small differential error voltage at the input terminals. Subsequently...(spice design added 02/09)

Constant Current Amplifier  - (diagram added 6/03)

Constant Current Power Amplifier  - (diagram added 6/03)

Controlled power supply increases OpAmps output voltage range - 03/15/07 EDN-Design Ideas: External transistors and op amps increase the outputvoltage range of a precision op amp.  (circuit.....(design idea added 6/07)

Current Feedback Amplifier Do's & Don'ts - DN46  Design Notes (Linear Technology) (app note added 1/06)

Current Feedback Amplifiers - National Semiconductor Application Note 05-Aug-1995 (app note added 4/02)

Current Source - Getting optimum performance in certain applications requires that some components, sensors, DC motors, transistors, be driven or biased by a constant current. We're mostly familiar with voltage regulators and their ability to maintain a constant voltage under varying current conditions. In this application, your challenge is to provide a constant ...(spice design added 02/09)

Current Source Enables OpAmp's Output to Go to Ground - 09/05/04 EDN-Design Ideas: The LM324 is a cost-effective choice for an op amp, especially when you need to apply ground-level inputs. Although its output purportedly includes ground, its poor current-sinking capability limits the applications. At output voltages lower than 0.5V, the op amp's sinking current ranges only from 2 to 100 µA.....(design idea added 1/05)