A wideband current feedback operational amplifier, the AD811 is optimized for broadcast-quality video systems. The -3 dB bandwidth of 120 MHz at a gain of +2 and differential gain and phase of 0.01% and 0.01° (RL = 150 W) make the AD811 an excellent choice for all video systems. The AD811 is designed to meet a stringent 0.1 dB gain flatness specification to a bandwidth of 35 MHz (G = +2) in addition to the low differential gain and phase errors. This performance is achieved whether driving one or two back terminated 75 W  cables, with a low power supply current of 16.5 mA. Furthermore, the AD811 is specified over a power supply range of ±4.5 V to ±18 V.The AD811 is also excellent for pulsed applications where transient response is crititcal. It can achieve a maximum slew rate of greater than 2500 V/µs with a settling time of less than 25 ns to 0.1% on a 2 V step and 65 ns to 0.01% on a 10 V step.The AD811 is ideal as an ADC or DAC buffer in data acquisition systems due to its low distortion up to 10 MHz and its wide unity gain bandwidth. Because the AD811 is a current feedback amplifier, this bandwidth can be maintained over a wide range of gains. The AD811 also offers low voltage and current noise of 1.9nV/√Hz and 20 pA/√Hz, respectively, and excellent dc accuracy for wide dynamic range applications.

A wideband current feedback operational amplifier, the AD811 is optimized for broadcast-quality video systems. The -3 dB bandwidth of 120 MHz at a gain of +2 and differential gain and phase of 0.01% and 0.01° (RL = 150 W) make the AD811 an excellent choice for all video systems. The AD811 is designed to meet a stringent 0.1 dB gain flatness specification to a bandwidth of 35 MHz (G = +2) in addition to the low differential gain and phase errors. This performance is achieved whether driving one or two back terminated 75 W  cables, with a low power supply current of 16.5 mA. Furthermore, the AD811 is specified over a power supply range of ±4.5 V to ±18 V.The AD811 is also excellent for pulsed applications where transient response is crititcal. It can achieve a maximum slew rate of greater than 2500 V/µs with a settling time of less than 25 ns to 0.1% on a 2 V step and 65 ns to 0.01% on a 10 V step.The AD811 is ideal as an ADC or DAC buffer in data acquisition systems due to its low distortion up to 10 MHz and its wide unity gain bandwidth. Because the AD811 is a current feedback amplifier, this bandwidth can be maintained over a wide range of gains. The AD811 also offers low voltage and current noise of 1.9nV/√Hz and 20 pA/√Hz, respectively, and excellent dc accuracy for wide dynamic range applications.

The AD8205 is a single-supply difference amplifier for amplify-ing small differential voltages in the presence of large common-mode voltages. The operating input common-mode voltage range extends from −2 V to +65 V. The typical single-supply voltage is 5 V.The AD8205 is offered in an 8-lead SOIC package and rated for operation from −40°C to +125°C for the Y and W grade models. The H grade version of the AD8205 is rated from −40°C to +150°C.Excellent dc performance over temperature keeps errors in the measurement loop to a minimum. Offset drift is typically less than 15 μV/°C, and gain drift is typically below 30 ppm/°C.The output offset can be adjusted from 0.05 V to 4.8 V with a 5 V supply by using the VREF1 and VREF2 pins. With VREF1 attached to the V+ pin, and VREF2 attached to the GND pin, the output is set at half scale. Attaching both pins to GND causes the output to be unipolar, starting near ground. Attaching both pins to V+ causes the output to be unipolar starting near V+. Other offsets can be obtained by applying an external voltage to the VREF1 and VREF2 pins.ApplicationsHigh-side current sensing in: Motor controls Transmission controls Diesel injection controls Engine management Suspension controls Vehicle dynamic controls DC-to-dc converters

The AD8206 is a single-supply difference amplifier for amplifying small differential voltages in the presence of large common-mode voltages. The operating input common-mode voltage range extends from -2 V to +65 V. The typical single-supply voltage is 5 V.The AD8206 is offered in an 8-lead SOIC package and it is rated throughout the automotive temperature range of −40°C to +125°C.Excellent DC performance over temperature keeps errors in the measurement loop to a minimum. Offset drift is typically less than 15 µV/°C, and gain drift is typically below 30 ppm/°C.The output offset can be adjusted from 0.08 V to 4.7 V witha 5 V supply by using the VREF1 and VREF2 pins. With VREF1 attached to the V+ pin, and VREF2 attached to the GND pin,the output is set at half scale. Attaching both pins to GND causes the output to be unipolar, starting near ground. Attaching both pins to V+ causes the output to be unipolar starting near V+. Other offsets can be obtained by applying an external voltage to the VREF1 and VREF2 pins.

The AD827 is a dual version of Analog Device's industry-standard AD847 op amp. Like the AD847, it provides high speed, low power performance at low cost. The AD827 achieves a 300 V/µs slew rate and 50 MHz unity-gain bandwidth while consuming only 100 mW when operating from ±5 volt power supplies. Performance is specified for operation using ±5 V to ±15 V power supplies.The AD827 offers an open-loop gain of 3,500 V/V into 500 Ohm loads. It also features a low input voltage noise of 15 nV/(root)Hz, and a low input offset voltage of 2 mV maximum. Common-mode rejection ratio is a minimum of 80 dB. Power supply rejection ratio is maintained at better than 20 dB with input frequencies as high as 1 MHz, thus minimizing noise feedthrough from switching power supplies.The AD827 is also ideal for use in demanding video applications, driving coaxial cables with less than 0.04% differential gain and 0.19° differential phase errors for 643 mV p-p into a 75 Ohm reverse terminated cable.The AD827 is also useful in multichannel, high speed data conversion systems where its fast (120 ns to 0.1%) settling time is of importance. In such applications, the AD827 serves as an input buffer for 8-bit to 10-bit A/D converters and as an output amplifier for high speed D/A converters.

The AD829 is a low noise (1.7 nV/√Hz), high speed op amp with custom compensation that provides the user with gains of 1 to 20 while maintaining a bandwidth >50 MHz. Its 0.04° differential phase and 0.02% differential gain performance at 3.58 MHz and 4.43 MHz, driving reverse-terminated 50 Ω or 75 Ω cables, makes it ideally suited for professional video applications. The AD829 achieves its 230 V/μs uncompensated slew rate and 750 MHz gain bandwidth while requiring only 5 mA of current from power supplies.The external compensation pin of the AD829 gives it exceptional versatility. For example, compensation can be selected to optimize the bandwidth for a given load and power supply voltage. As a gain-of-2 line driver, the −3 dB bandwidth can be increased to 95 MHz at the expense of 1 dB of peaking. Its output can also be clamped at its external compensation pin.The AD829 exhibits excellent dc performance. It offers a minimum open-loop gain of 30 V/mV into loads as low as 500 Ω, a low input voltage noise of 1.7 nV/√Hz, and a low input offset voltage of 1 mV maximum. Common-mode rejection and power supply rejection ratios are both 120 dB.This op amp is also useful in multichannel, high speed data conversion where its fast (90 ns to 0.1%) settling time is important. In such applications, the AD829 serves as an input buffer for 8-bit to 10-bit ADCs and as an output I/V converter for high speed DACs.Operating as a traditional voltage feedback amplifier, the AD829 provides many of the advantages that a transimpedance amplifier offer. A bandwidth >50 MHz can be maintained for a range of gains through the replacement of the external compensation capacitor. The AD829 and the transimpedance amplifier are both unity-gain stable and provide similar voltage noise performance (1.7 nV/√Hz); however, the current noise of the AD829 (1.5 pA/√Hz) is less than 10% of the noise of transimpedance amplifiers. The inputs of the AD829 are symmetrical.

The AD829 is a low noise (1.7 nV/√Hz), high speed op amp with custom compensation that provides the user with gains of 1 to 20 while maintaining a bandwidth >50 MHz. Its 0.04° differential phase and 0.02% differential gain performance at 3.58 MHz and 4.43 MHz, driving reverse-terminated 50 Ω or 75 Ω cables, makes it ideally suited for professional video applications. The AD829 achieves its 230 V/μs uncompensated slew rate and 750 MHz gain bandwidth while requiring only 5 mA of current from power supplies.The external compensation pin of the AD829 gives it exceptional versatility. For example, compensation can be selected to optimize the bandwidth for a given load and power supply voltage. As a gain-of-2 line driver, the −3 dB bandwidth can be increased to 95 MHz at the expense of 1 dB of peaking. Its output can also be clamped at its external compensation pin.The AD829 exhibits excellent dc performance. It offers a minimum open-loop gain of 30 V/mV into loads as low as 500 Ω, a low input voltage noise of 1.7 nV/√Hz, and a low input offset voltage of 1 mV maximum. Common-mode rejection and power supply rejection ratios are both 120 dB.This op amp is also useful in multichannel, high speed data conversion where its fast (90 ns to 0.1%) settling time is important. In such applications, the AD829 serves as an input buffer for 8-bit to 10-bit ADCs and as an output I/V converter for high speed DACs.Operating as a traditional voltage feedback amplifier, the AD829 provides many of the advantages that a transimpedance amplifier offer. A bandwidth >50 MHz can be maintained for a range of gains through the replacement of the external compensation capacitor. The AD829 and the transimpedance amplifier are both unity-gain stable and provide similar voltage noise performance (1.7 nV/√Hz); however, the current noise of the AD829 (1.5 pA/√Hz) is less than 10% of the noise of transimpedance amplifiers. The inputs of the AD829 are symmetrical.

The AD8305 is an inexpensive microminiature logarithmic converter optimized for determining optical power in fiber optic systems. It uses an advanced implementation of a classic translinear (junction based) technique to provide a large dynamic range in a versatile and easily used form. A single-supply voltage of between 3 V and 12 V is adequate; dual supplies may optionally be used. The low quiescent current (typically 5 mA) permits use in battery-operated applications.The input current, IPD, of 10 nA to 1 mA applied to the INPT pin is the collector current of an optimally scaled NPN transistor, which converts this current to a voltage (VBE) with a precise logarithmic relationship. A second such converter is used to handle the reference current (IREF) applied to pin IREF. These input nodes are biased slightly above ground (0.5 V). This is generally acceptable for photodiode applications where the anode does not need to be grounded. Similarly, this bias voltage is easily accounted for in generating IREF. The output of the logarithmic front end is available at Pin VLOG.The basic logarithmic slope at this output is nominally 200 mV/decade (10 mV/dB). Thus, a 100 dB range corresponds to an output change of 1 V. When this voltage (or the buffer output) is applied to an ADC that permits an external reference voltage to be employed, the AD8305 voltage reference output of 2.5 V at Pin VREF can be used to improve the scaling accuracy. Suitable ADCs include the AD7810 (serial 10-bit), AD7823 (serial 8-bit), and AD7813 (parallel, 8-bit or 10-bit). Other values of the logarithmic slope can be provided using a simple external resistor network.The logarithmic intercept (also known as the reference current) is nominally positioned at 1 nA by the use of the externally generated current, IREF, of 10 μA, provided by a 200 kΩ resistor connected between VREF, at 2.5 V, and the reference input, IREF, at 0.5 V. The intercept can be adjusted over a wide range by varying this resistor. The AD8305 can also operate in a log ratio mode, with the numerator current applied to INPT and the denominator current applied to IREF.A buffer amplifier is provided for driving a substantial load, for use in raising the basic slope of 10 mV/dB to higher values, as a precision comparator (threshold detector), or in implementing low-pass filters. Its rail-to-rail output stage can swing to within 100 mV of the positive and negative supply rails, and its peak current sourcing capacity is 25 mA.It is a fundamental aspect of translinear logarithmic converters that the small signal bandwidth falls as the current level diminishes, and the low frequency noise-spectral density increases. At the 10 nA level, the bandwidth of the AD8305 is about 50 kHz and increases in proportion to IPD up to a maximum value of about 15 MHz. Using the buffer amplifier, the increase in noise level at low currents can be addressed by using it to realize lowpass filters of up to three poles.The AD8305 is available in a 16-lead LFCSP package and is specified for operation from −40°C to +85°C.Applications  Optical power measurement Wide range baseband logarithmic compression Measurement of current and voltage ratios Optical absorbance measurement

The AD8312 is a complete, low cost subsystem for the measurement of RF signals in the frequency range of 50 MHz to 3.5 GHz. It has a typical dynamic range of 45 dB and is intended for use in a wide variety of cellular handsets and other wireless devices. It provides a wider dynamic range and better accuracy than possible using discrete diode detectors. In particular, its temperature stability is excellent over the full operating range of −40°C to +85°C.Its high sensitivity allows measurement at low power levels, thus reducing the amount of power that needs to be coupled to the detector. It is essentially a voltage-responding device, with a typical signal range of 1.25 mV to 224 mV rms or −45 dBm to 0 dBm, referencing 50 Ω.For convenience, the signal is internally ac-coupled, using a 5 pF capacitor to a load of 3 kΩ in shunt with 1.3 pF. This high-pass coupling, with a corner at approximately 16 MHz, determines the lowest operating frequency. Therefore, the source may be dc grounded.The AD8312 output, VOUT, increases from close to ground to about 1.2 V because the input signal level increases from 1.25 mV to 224 mV. A capacitor may be connected between the VOUT and CFLT pins when it is desirable to increase the time interval over which averaging of the input waveform occurs.The AD8312 is available in a 6-ball, 1.0 mm × 1.5 mm, wafer-level chip scale package and consumes 4.2 mA from a 2.7 V to 5.5 V supply.Applications Cellular handsets (GSM, CDMA, WCDMA) RSSI and TSSI for wireless terminal devices Transmitter power measurement

The AD8335 is a quad variable gain amplifier (VGA) with low noise preamplifier intended for cost and power sensitive applications. Each channel features a gain range of 48 dB, fully differential signal paths, active input preamplifier matching, and user-selectable maximum gains of 46 dB and 38 dB. Individual gain controls are provided for each channel.The preamplifier (PrA) has a single-ended to differential gain of ×8 (18.06 dB) and accepts input signals 625 mV p-p. PrA noise is 1.2 nV/√Hz and the combined input referred voltage noise of the PrA and VGA is 1.3 nV/√Hz at maximum gain.Assuming a 20 MHz noise bandwidth (NBW), the Nyquist frequency for a 40 MHz ADC, the input SNR is 92 dB. The HLxx pin optimizes the output SNR for 10-bit and 12-bit ADCs with 1 V p-p or 2 V p-p full-scale (FS) inputs.Channel 1 and Channel 2 are enabled through the EN12 pin and Channel 3 and Channel 4 are enabled through the EN34 pin. For VGA only applications, the PrAs can be powered down, significantly reducing power consumption.The AD8335 is available in a 64-lead lead frame chip scale package (9 mm × 9 mm) for the industrial temperature range of −40°C to +85°C.ApplicationsMedical imaging (ultrasound, gamma cameras)SonarTest and measurementPrecise, stable wideband gain controlData Sheet, Rev A, 08/2008