AD7755AAN

Product Summary

The AD7755AAN is a high accuracy electrical energy measurement IC. The part specifications surpass the accuracy requirements as quoted in the IEC1036 standard. See Analog Devices’Application Note AN-559 for a description of an IEC1036 watt-hour meter reference design. The only analog circuitry used in the AD7755AAN is in the ADCs and reference circuit. All other signal processing (e.g., multiplication and filtering) is carried out in the digital domain. This approach provides superior stability and accuracy over extremes in environmental conditions and over time.

Parametrics

AD7755AAN absolute maximum ratings: (1)AVDD to AGND: –0.3 V to +7 V; (2)DVDD to DGND: –0.3 V to +7 V; (3)DVDD to AVDD: –0.3 V to +0.3 V; (4)Analog Input Voltage to AGND V1P, V1N, V2P and V2N: –6 V to +6 V; (5)Reference Input Voltage to AGND: –0.3 V to AVDD + 0.3 V; (6)Digital Input Voltage to DGND: –0.3 V to DVDD + 0.3 V; (7)Digital Output Voltage to DGND: –0.3 V to DVDD + 0.3 V; (8)Operating Temperature Range Industrial (A, B Versions): –40℃ to +85℃; (9)Storage Temperature Range: –65℃ to +150℃; (10)Junction Temperature: 150℃; (11)24-Lead Plastic DIP, Power Dissipation: 450 mW; (12)θJA Thermal Impedance: 105℃/W; (13)Lead Temperature, (Soldering 10 sec): 260℃; (14)24-Lead SSOP, Power Dissipation: 450 mW; (15)θJA Thermal Impedance: 112℃/W; (16)Lead Temperature, Soldering Vapor Phase (60 sec): 215℃; (17)Infrared (15 sec): 220℃.

Features

AD7755AAN features: (1)High Accuracy, Supports 50 Hz/60 Hz IEC 687/1036 Less than 0.1% Error Over a Dynamic Range of 500 to 1; (2)The AD7755 Supplies Average Real Power on the Frequency Outputs F1 and F2; (3)The High Frequency Output CF Is Intended for Calibration and Supplies Instantaneous Real Power; (4)The Logic Output REVP Can Be Used to Indicate a Potential Miswiring or Negative Power Direct Drive for Electromechanical Counters and Two Phase Stepper Motors (F1 and F2); (5)A PGA in the Current Channel Allows the Use of Small Values of Shunt and Burden Resistance; (6)Proprietary ADCs and DSP Provide High Accuracy over Large Variations in Environmental Conditions and Time; (7)On-Chip Power Supply Monitoring; (8)On-Chip Creep Protection (No Load Threshold); (9)On-Chip Reference 2.5 V 6 8% (30 ppm/8C Typical) with External Overdrive Capability; (10)Single 5 V Supply, Low Power (15 mW Typical); (11)Low Cost CMOS Process.

Diagrams