Biasing and Decoupling Op Amps in Single Supply Applications:  AN-581 - Analog Devices Application Notes  (added 2/06)

Capacitance Meter:  Auto ranged capacitance meter. It can measure up to several 100µF in minimum resolution of 0.1pF.  (added 10/05)

Capacitance Meter:  This is a simple capacitance meter which can measure capacitance value easy. There are some measurement methods for capacitance, at one time the capacitance was measured with a impedance bridge or a dip meter. Recently typical capacitance meters can measure capacitance and some additional characteristics from current vector by applying AC voltage to the Cx. Some simple capacitance meter use integration method that measuring transient response of the R-C network. There are some construction kits based on this method.  This project uses the integration method. There are some merits that the result can be got as digital data directly because it bases measurement of time, accurate analog circuit is not required and its calibration can be done easy by using a microcontroller. Therefore the integration method is suitable for hand built capacitance meter with high reliability....  (Schematic / circuit added 10/05)

Careful Design Tames High Speed Op Amps:  AN-257 - Analog Devices Application Notes  (added 2/06)

Designing With A New Family Of Instrumentation Amplifiers:  DN40 -  Design Notes (Linear Technology) (added 1/06)

Difference Amplifier Measures High Voltages:  04/28/05   EDN-Design Ideas / (added 5/05)

Difference Amplifier Uses Digital Potentiometers:  05/30/02 EDN Design Ideas  /  (added 12/04)  You sometimes need to measure a small signal in the presence of a large common-mode signal. Traditional instrumentation amplifiers that use two or three op amps in their internal structure find common use in these applications. The circuit in Figure 1 presents an alternative approach that is useful when low cost and low drift are important, but when you don't need high precision....

Differential Amp Drives High-Speed ADC:  06/21/01 EDN-Design Ideas / (added 5/03) The schematic in Figure 1 is the discrete-element version of an A/D-converter drive circuit. The circuit converts a single-ended input to a differential output. The ADC's reference voltage determines the common-mode range of the differential outputs. The circuit contains two AD9631 amplifiers—one connected in noninverting mode, and the other connected in inverting mode. The OP279 amplifiers buffer and scale the ADC's reference voltage to set the common-mode range of the two outputs. The circuit in Figure 1 requires many resistors. The two 15W resistors help prevent oscillation arising from the capacitive inputs of the ADC. The circuit has several disadvantages, such as poor gain accuracy, high distortion, and limited speed. The circuit in Figure 2 is an improved ADCdriver....

Differential Amp Needs No Power Source:  05/02/02 EDN Design Ideas  /  (added 12/04)  A true-differential, power-source-free, high-input-impedance amplifier with bipolar output would present distinct advantages in remote devices. Such an amplifier, with its bipolar output, would be a better choice than a unipolar, 4- to 20-mA device. It would also improve on common-mode performance. In Figure 1, a Maxim MAX319 analog switch, IC2, feeds the power from the coaxial signal cable to ......

Easy-To-Use Differential Amplifiers Simplify Balanced Signal Designs:  DN333 -  Design Notes (Linear Technology) (added 1/06)