Analog Devices ADE7913/ADE7912
Isolated, Sigma Delta ADCs with SPI
Analog Devices ADE7913/ADE7912 are fully isolated analog-to-digital
converters (ADCs) designed for a variety of applications such as
shunt-based polyphase meters, power quality monitoring, solar inverters,
process monitoring and protective devices. The devices incorporate
Analog Devices' patented iCoupler® and isoPower® technologies to
implement isolated signal transfer and DC-to-DC power conversion across a
5kV-rated insulation barrier. This integration enables the use of
shunt resistor sensing elements instead of current transformers (CTs),
thereby providing immunity to magnetic field interference and tampering.
The use of shunts instead of CTs also reduces system cost and size.
ADE7912 features two 24-bit ADCs, and the ADE7913 features three ADCs.
The current ADC provides a 67dB signal-to-noise ratio over a 3kHz
signal bandwidth, whereas the voltage ADCs provide a SNR of 72dB over
the same bandwidth. One channel is dedicated to measuring the voltage
across a shunt when the shunt is used for current sensing. Up to two
additional channels are dedicated to measuring voltages, which are
usually sensed using resistor dividers. One voltage channel can be used
to measure the temperature of the die via an internal sensor. The
ADE7913 includes three channels: one current and two voltage channels.
The ADE7912 has one voltage channel but is otherwise identical to the