AN-356: User's Guide to Applying and Measuring Operational Amplifier Specifications:    AN-356 Analog Devices Application Notes  (app note added 6/06)

AN-589: Ways to Optimize the Performance of a Difference Amplifier:    AN-589 Analog Devices Application Notes  (app note added 6/06) This Application Note presents several ways to build and optimize  performance of a discrete difference amplifier. It also recommends amplifiers that will make  overall solution cost/performance competitive with monolithic instrument amplifiers.

AN867: Temperature Sensing with a Programmable Gain Amplifier:    Microchip Application Note Published 26-Jun-03   (app note added 2/06)

Analog Input Circuit Serves Any Microcontroller:    12/20/01 EDN Design Ideas / (added 10/03)  The simple ADC in Figure 1 is perfect for getting analog signals into a purely digital microcontroller. Using just five surface-mount parts, you can assemble it for less than 50 cents (1000), which is approximately half  cost of a single-chip- ADC approach in  same volume. Moreover, this design takes only one pin from  microcontroller to operate. .

Circuit Performs High Speed Voltage to Current Current to Current Conversion:    07)/25/02 EDN Design Ideas  /  (added 12/04)  The circuit in Figure 1performs active voltage-to-current conversion or acts as a variable-gain current mirror with high precision and bandwidth. A typical application is testing high-speed ICs or other devices that have inputs designed to be driven from current-steering DACs to enable a modulated voltage source to control the devices....

LED Driver Delivers Constant Luminosity:    06/12/03 EDN Design Ideas  /  (added 12/04)  The circuit in Figure 1 is similar in principle to that of a previous Design Idea (Reference 1) but offers improved, more reproducible performance. The output current is almost constant over an input-voltage range of 1.2 to 1.5V and is insensitive to variations of transistor gain. Transistors Q1 and Q2 form an astable flip-flop....

LX5506M High Gain, High Efficiency Power Amplifier Also see LX5506 and LX5506B-AN-36:    Application Note 36 from Microsem  (app note added 6/06)

Network Imitates Thermocouples:    11/08/01 EDN Design Ideas  /  (added 12/04)  Thermocouples find widespread use for temperature measurement in systems. During system design or testing, you must observe the system's response at different temperatures. However, it's inconvenient to heat a thermocouple every time you need to check a system's performance. You can use the simple trick of touching the thermocouple with a hot soldering iron, but this method provides only ... ...

Positive Feedback Yields Fast Amplifier with Precision DC Offset:    04/01/04 EDN Design Ideas  /  (added 1/05)  Some signal-processing applications require a high-speed, low-noise, dc-coupled amplifier that incorporates a precision dc-offset adjustment. Examples include oscilloscopes, in which the offset adjustment typically acts as a "position" control), ADC-input gain blocks, and scanning-ion-beam-microscopy deflection circuitry....

Precise Gain Without External Resistors:    DN348  Design Notes (Linear Technology)  (app note added 1/06)

Programmable Gain Amplifier is Low Cost:    01/18/01 EDN Design Ideas / (added 09/05)  Numerous programmable-gain amplifiers are available, but a simple solution provides the option of using 256 gain steps with an 8-bit DAC and higher steps with higher bit DACs (Figure 1). According to the inverting-amplifier configuration of an op amp, the output voltage is VOUT=VIN(RF/RIN), where RF is the feedback resistance, RIN is the input resistance, and VIN is the input voltage of the amplifier circuit. Generally, by changing the feedback resistance, you can get the desired gain.

Sensing Light with a Programmable Gain Amplifier:    Microchip Application Note Published 28-Mar-03   (app note added 6/06)

Simple 0 to 24 dB Gain Amplifier and Balanced Line Driver:    AS022 Jenson Transformer Application Note  (app note 6/07)

Temperature Sensing with a Programmable Gain Amplifier:    Microchip Application Note Published 26-Jun-03   (app note added 2/06)

Transmitter Accurately Transfers Voltage Input:    05/15/03 EDN Design Ideas  /  (added 12/04)  When you connect remote sensors to a central process controller, a simple, robust, and commonly used interface is the 4to 20-mA loop. The advantages of this current loop include the simplicity of just two twisted wires that share both power and signal, the loop's high noise immunity in harsh environments, and the de facto loop standard within the process-control industry....

User's Guide to Applying and Measuring Operational Amplifier Specifications:    AN-356 Analog Devices Application Notes  (app note added 6/06)

Voltage to Current Converter Drives White LEDs:    06/27/02 EDN Design Ideas  /  (added 12/04)  You sometimes need to drive a white LED from one 1.5V battery. Unfortunately, the forward voltage of a white LED is 3 to 4V. So, you would need a dc/dc converter to drive the LED from one battery. Using the simple circuit in Figure 1, you can drive one white LED or two series-connected green LEDs, using only a few components....

Voltage to Current Converter Makes a Flexible Current Reference:    09/18/03 EDN Design Ideas  /  (added 12/04)  The voltage-to-current converter in Figure 1 can both source and sink current. The circuit is more flexible than some traditional current references that require different topologies for current sourcing and sinking. Also, you can easily adjust the value of the current reference by simply adjusting the circuit's input voltage....

Ways to Optimize the Performance of a Difference Amplifier:    AN-589 Analog Devices Application Notes  (app note added 6/06) This Application Note presents several ways to build and optimize the performance of a discrete difference amplifier. It also recommends amplifiers that will make the overall solution cost/performance competitive with monolithic instrument amplifiers.