Analog Devices

The AD623 is an integrated, single- or dual-supply instrumentation amplifier that delivers rail-to-rail output swing using supply voltages from 2.7 V to 12 V. The AD623 offers user flexibility by allowing single gain set resistor programming and by conforming to the 8-lead industry standard pinout configuration. With no external resistor, the AD623 is configured for unity gain (G = 1), and with an external resistor, the AD623 can be programmed for gains of up to 1000.The accuracy of the AD623 is the result of increasing ac common-mode rejection ratio (CMRR) coincident with increasing gain. Line noise harmonics are rejected due to constant CMRR up to 200 Hz. The AD623 has a wide input common-mode range and amplifies signals with common-mode voltages as low as 150 mV below ground. The AD623 maintains optimal performance with dual and single polarity power supplies.ApplicationsLow power medical instrumentationTransducer interfacesThermocouple amplifiersIndustrial process controlsDifference amplifiersLow power data acquisition

The AD624 is a high precision, low noise, instrumentation amplifier designed primarily for use with low level transducers, including load cells, strain gauges and pressure transducers. An combination of low noise, high gain accuracy, low gain temperature coefficient and high linearity make the AD624 ideal for use in high resolution data acquisition systems.The AD624C has an input offset voltage drift of less than 0.25 µV/°C, output offset voltage drift of less than 10 µV/°C, CMRR above 80 dB at unity gain (130 dB at G = 500) and a maximum nonlinearity of 0.001% at G = 1. In addition to these outstanding dc specifications, the AD624 exhibits superior ac performance as well. A 25 MHz gain bandwidth product, 5 V/µs slew rate and 15 µs settling time permit the use of the AD624 in high speed data acquisition applications.The AD624 does not need any external components for trimmed gains of 1, 100, 200, 500 and 1000. Additional gains such as 250 and 333 can be programmed within one percent accuracy with external jumpers. A single external resistor can also be used to set the 624's gain to any value in the range of 1 to 10,000.

The AD625 is a precision instrumentation amplifier specifically designed to fulfill two major areas of application: 1) Circuits requiring nonstandard gains (i.e., gains not easily achievable with devices such as the AD524 and AD624). 2) Circuits requiring a low cost, precision software programmable gain amplifier.For low noise, high CMRR, and low drift the AD625JN is the most cost effective instrumentation amplifier solution available. An additional three resistors allow the user to set any gain from 1 to 10,000. The error contribution of the AD625JN is less than 0.05% gain error and under 5 ppm/°C gain TC; performance limitations are primarily determined by the external resistors. Common-mode rejection is independent of the feedback resistor matching.A software programmable gain amplifier (SPGA) can be configured with the addition of a CMOS multiplexer (or other switch network), and a suitable resistor network. Because the ON resistance of the switches is removed from the signal path, an AD625 based SPGA will deliver 12-bit precision, and can be programmed for any set of gains between 1 and 10,000, with completely user selected gain steps.For the highest precision the AD625C offers an input offset voltage drift of less than 0.25 µV/°C, output offset drift below 15 µV/°C, and a maximum nonlinearity of 0.001% at G = 1. All grades exhibit excellent ac performance; a 25 MHz gain bandwidth product, 5 V/µs slew rate and 15 µs settling time.The AD625 is available in three accuracy grades (A, B, C) for industrial (-40°C to +85°C) temperature range, two grades (J, K) for commercial (0°C to +70°C) temperature range, and one (S) grade rated over the extended (-55°C to +125°C) temperature range.

The AD627 is an integrated, micropower instrumentation amplifier that delivers rail-to-rail output swing on single and dual (+2.2 V to ±18 V) supplies. The AD627 provides excellent ac and dc specifications while operating at only 85 μA maximum.The AD627 offers superior flexibility by allowing the user to set the gain of the device with a single external resistor while con-forming to the 8-lead industry-standard pinout configuration. With no external resistor, the AD627 is configured for a gain of 5. With an external resistor, it can be set to a gain of up to 1000.A wide supply voltage range (+2.2 V to ±18 V) and micropower current consumption make the AD627 a perfect fit for a wide range of applications. Single-supply operation, low power consumption, and rail-to-rail output swing make the AD627 ideal for battery-powered applications. Its rail-to-rail output stage maximizes dynamic range when operating from low supply voltages. Dual-supply operation (±15 V) and low power consumption make the AD627 ideal for industrial applications, including 4 to 20 mA loop-powered systems.The AD627 does not compromise performance, unlike other micropower instrumentation amplifiers. Low voltage offset, offset drift, gain error, and gain drift minimize errors in the system. The AD627 also minimizes errors over frequency by providing excellent CMRR over frequency. Because the CMRR remains high up to 200 Hz, line noise and line harmonics are rejected.The AD627 provides superior performance, uses less circuit board area, and costs less than micropower discrete designs.Applications4 mA to 20 mA loop-powered applicationsLow power medical instrumentation—ECG, EEGTransducer interfacingThermocouple amplifiersIndustrial process controlsLow power data acquisitionPortable battery-powered instruments

The AD628 is a precision difference amplifier that combines excellent dc performance with high common-mode rejection over a wide range of frequencies. When used to scale high voltages, it allows simple conversion of standard control voltages or currents for use with single-supply ADCs. A wideband feedback loop minimizes distortion effects due to capacitor charging of Σ-Δ ADCs.A reference pin (VREF) provides a dc offset for converting bipolar to single-sided signals. The AD628 converts +5 V, +10 V, ±5 V, ±10 V, and 4 to 20 mA input signals to a single-ended output within the input range of single-supply ADCs.The AD628 has an input common mode and differential mode operating range of ±120 V. The high common mode, input impedance makes the device well suited for high voltage measurements across a shunt resistor. The inverting input of the buffer amplifier is available for making a remote Kelvin connection.A precision 10 kΩ resistor connected to an external pin is provided for either a low-pass filter or to attenuate large differential input signals. A single capacitor implements a low-pass filter. The AD628 operates from single and dual supplies and is available in an 8-lead SOIC_N or an 8-lead MSOP. It operates over the standard industrial temperature range of −40°C to +85°C.ApplicationsHigh voltage current shunt sensingProgrammable logic controllersAnalog input front end signal conditioning+5 V, +10 V, ±5 V, ±10 V, and 4 to 20 mAIsolation Sensor signal conditioningPower supply monitoringElectrohydraulic controlsMotor controls

The AD629 is a difference amplifier with a very high input, common-mode voltage range. It is a precision device that allows the user to accurately measure differential signals in the presence of high common-mode voltages up to ±270 V.The AD629 can replace costly isolation amplifiers in applications that do not require galvanic isolation. The device operates over a ±270 V common-mode voltage range and has inputs that are protected from common-mode or differential mode transients up to ±500 V.The AD629 has low offset, low offset drift, low gain error drift, low common-mode rejection drift, and excellent CMRR over a wide frequency range.The AD629 is available in low cost, 8-lead PDIP and 8-lead SOIC packages. For all packages (including die) and grades, performance is guaranteed over the industrial temperature range of −40°C to +85°C.ApplicationsHigh voltage current sensingBattery cell voltage monitorsPower supply current monitorsMotor controlsIsolation

The AD632 is an internally trimmed monolithic four-quadrant multiplier/divider. The AD632B has a maximum multiplying error of ±0.5% without external trims.Excellent supply rejection, low temperature coefficients and long term stability of the on-chip thin film resistors and buried zener reference preserve accuracy even under adverse conditions. The simplicity and flexibility of use provide an attractive alternative approach to the solution of complex control functions.The AD632 is pin-for-pin compatible with the industry standard AD532 with improved specifications and a fully differential high impedance Z-input. The AD632 is capable of providing gains of up to X10, frequently eliminating the need for separate instrumentation amplifiers to precondition the inputs. The AD632 can be effectively employed as a variable gain differential input amplifier with high common-mode rejection. The effectiveness of the variable gain capability is enhanced by the inherent low noise of the AD632: 90 µV rms.APPLICATIONSHigh quality analog signal processingDifferential ratio and percentage computationsAlgebraic and trigonometric function synthesisAccurate voltage controlled oscillators and filtersPRODUCT HIGHLIGHTSGuaranteed performance over temperature.The AD632A and AD632B are specified for maximum multiplying errors of ±1.0% and ±0.5% of full scale, respectively, at +25°C and are rated for operation from −25°C to +85°C.Maximum multiplying errors of ±2.0% (AD632S) and ±1.0% (AD632T) are guaranteed over the extended temperature range of −55°C to +125°C.High reliability.The AD632S and AD632T series are available with MIL-STD-883 Level B screening.All devices are available in either the hermetically sealed TO-100 metal can or ceramic DIP package.

The AD633 is a functionally complete, four-quadrant, analog multiplier. It includes high impedance, differential X and Y inputs, and a high impedance summing input (Z). The low impedance output voltage is a nominal 10 V full scale provided by a buried Zener. The AD633 is the first product to offer these features in modestly priced 8-lead PDIP and SOIC packages.The AD633 is laser calibrated to a guaranteed total accuracy of 2% of full scale. Nonlinearity for the Y input is typically less than 0.1% and noise referred to the output is typically less than 100 μV rms in a 10 Hz to 10 kHz bandwidth. A 1 MHz bandwidth, 20 V/μs slew rate, and the ability to drive capacitive loads make the AD633 useful in a wide variety of applications where simplicity and cost are key concerns.The versatility of the AD633 is not compromised by its simplicity. The Z input provides access to the output buffer amplifier, enabling the user to sum the outputs of two or more multipliers, increase the multiplier gain, convert the output voltage to a current, and configure a variety of applications.The AD633 is available in 8-lead PDIP and SOIC packages. It is specified to operate over the 0°C to 70°C commercial temperature range (J Grade) or the −40°C to +85°C industrial temperature range (A Grade).Product HighlightsThe AD633 is a complete four-quadrant multiplier offered in low cost 8-lead SOIC and PDIP packages. The result is a product that is cost effective and easy to apply.No external components or expensive user calibration are required to apply the AD633.Monolithic construction and laser calibration make the device stable and reliable.High (10 MΩ) input resistances make signal source loading negligible.Power supply voltages can range from ±8 V to ±18 V. The internal scaling voltage is generated by a stable Zener diode; multiplier accuracy is essentially supply insensitive.ApplicationsMultiplication, division, squaringModulation/demodulation, phase detectionVoltage-controlled amplifiers/attenuators/filters

The AD636 is a low power monolithic IC that performs true rms-to-dc conversion on low level signals. It offers performance that is comparable or superior to that of hybrid and modular converters costing much more. The AD636 is specified for a signal range of 0 mV to 200 mV rms. Crest factors up to 6 can be accommodated with less than 0.5% additional error, allowing accurate measurement of complex input waveforms.The low power supply current requirement of the AD636, typically 800 μA, is ideal for battery-powered portable instruments. It operates from a wide range of dual and single power supplies, from ±2.5 V to ±16.5 V or from +5 V to +24 V. The input and output terminals are fully protected; the input signal can exceed the power supply with no damage to the device (allowing the presence of input signals in the absence of supply voltage), and the output buffer amplifier is short-circuit protected.The AD636 includes an auxiliary dB output derived from an internal circuit point that represents the logarithm of the rms output. The 0 dB reference level is set by an externally supplied current and can be selected to correspond to any input level from 0 dBm (774.6 mV) to −20 dBm (77.46 mV). Frequency response ranges from 1.2 MHz at 0 dBm to greater than 10 kHz at −50 dBm.The AD636 is easy to use. The device is factory-trimmed at the wafer level for input and output offset, positive and negative waveform symmetry (dc reversal error), and full-scale accuracy at 200 mV rms. Therefore, no external trims are required to achieve full-rated accuracy.The AD636 is available in two accuracy grades. The total error of the J-version is typically less than ±0.5 mV ± 1.0% of reading, while the total error of the AD636K is less than ±0.2 mV to ±0.5% of reading. Both versions are temperature rated for operation between 0°C and 70°C and available in 14-lead SBDIP and 10-lead TO-100 metal can.The AD636 computes the true root-mean-square of a complex ac (or ac plus dc) input signal and gives an equivalent dc output level. The true rms value of a waveform is a more useful quantity than the average rectified value because it is a measure of the power in the signal. The rms value of an ac-coupled signal is also its standard deviation.The 200 mV full-scale range of the AD636 is compatible with many popular display-oriented ADCs. The low power supply current requirement permits use in battery-powered hand-held instruments. An averaging capacitor is the only external component required to perform measurements to the fully specified accuracy is. Its value optimizes the trade-off between low frequency accuracy, ripple, and settling time.An optional on-chip amplifier acts as a buffer for the input or the output signals. Used in the input, it provides accurate performance from standard 10 MΩ input attenuators. As an output buffer, it sources up to 5 mA.