ADE7913:  3-Channel, Isolated, Sigma Delta ADC with SPI

The ADE7913/ADE7912 are isolated three-input channel, analog to digital converter (ADC) for polyphase energy metering applications using shunt current sensors. They feature three 24-bit analog to digital converters, each of which provides 70dB signal to noise ratio over a 3 kHz signal bandwidth. One channel is dedicated to measuring the voltage across a shunt when the shunt is used for current sensing. Two additional channels are dedicated to measuring voltages, which are usually sensed using resistor dividers. One of these channels may be used to measure the temperature measurement of the die, using an internal sensor. The ADE7913 includes all the current, voltage and temperature measurements. The ADE7912 is the same as the ADE7913 but it does not include the second voltage measurement.

The ADE7913/ADE7912 include isoPower®, an integrated, isolated dc-to-dc converter. Based on the Analog Devices, Inc., iCoupler® technology, the dc-to-dc converter provides the regulated power required by the first stage of the ADCs at 3.3V input supply. This device eliminates the need for an external dc-to-dc isolation block. The iCoupler chip scale transformer technology is also used to isolate the logic signals between the first and second stages of the ADC. The result is a small form factor, total isolation solution.

The ADE7913/ADE7912 contain a bidirectional SPI serial port interface. It provides access to the ADC outputs, configuration and status registers for easy interfacing with microcontrollers.

The ADE7913/ADE7912 can be clocked from a crystal or an external clock signal. To minimize the system’s bill of materials, the master ADE7913/ADE7912 can drive clocks of up to three additional ADE7913/ADE7912s.

Multiple ADE7913/ADE7912s may be synchronized to sample in the same moment and provide coherent outputs.

The ADE7913/ADE7912 is available in the 20-lead wide body SOIC Pb-free package with increased creepage.

• Shunt based polyphase meters
• Power quality monitoring
• Solar inverters
• Process monitoring
• Protective devices