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The HCPL-7800(A) isolation amplifier family was designed for current sensing in electronic motor drives. In a typical
implementation, motor currents flow through an external resistor and the resulting analog voltage drop is sensed by the HCPL-7800(A). A differential output voltage iscreated on the other side of the HCPL-7800(A) optical is olation barrier. This differential output voltage is proportional to the motor current and can be converted to a single-ended signal by using an op-amp as shown in
the recommended application circuit. Since commonmode voltage swings of several hundred volts in tens of nanoseconds are common in modern switching inverter motor drives, the HCPL-7800(A) was designed to ignore very high common-mode transient slew rates (of at least10 kV/μs).The high CMR capability of the HCPL-7800(A) isolation amplifier provides the precision and
stability needed to accurately monitor motor current in high noise motor control environ-ments, providing for smoother control
(less "torque ripple") in various types of motor control applications.The product can also be used for general analog signal isolation applications requiring high accuracy, stability,and linearity under similarly severe noise con-ditions. For general applications, we recommend the HCPL-7800(gain tolerance of ±3%). For precision applications Avago Technologies offers the HCPL-7800A with part-to-part gain tolerance of ±1%. The HCPL-7800(A) utilizes sigma delta (Σ?△) analog-to-digital converter technology,chopper stabilized amplifiers, and a fully differential circuit topology.Together, these features deliver unequaled isolationmode noise rejection, as well as excellent offset and gain accuracy and stability over time and temperature.This performance is delivered in a compact, auto-insertable,industry standard 8-pin DIP package that meets worldwide regulatory safety standards. (A gull-wing
surface mount option #300 is also available).

? Motor Phase and Rail Current Sensing
? Inverter Current Sensing
? Switched Mode Power Supply Signal Isolation
? General Purpose Current Sensing and Monitoring
? General Purpose Analog Signal Isolation

? 15 kV/μs Common-Mode Rejection at VCM = 1000 V
? Compact, Auto-Insertable Standard 8-pin DIP Package
? 0.00025 V/V/°C Gain Drift vs. Temperature
? 0.3 mV Input Offset Voltage
? 100 kHz Bandwidth
? 0.004% Nonlinearity
? Worldwide Safety Approval: UL 1577 (3750 Vrms/1 min.)
and CSA, IEC/EN/DIN EN 60747-5-2
? Advanced Sigma-Delta (Σ?) A/D Converter Technology
? Fully Differential Circuit Topology