IL715/IL716/IL717
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NVE Corporation 11409 Valley View Road, Eden Prairie, MN 55344-3617 Phone: (952) 829-9217 Fax: (952) 829-9189 www.IsoLoop.com ©NVE Corporation
Application Information
Electrostatic Discharge Sensitivity
This product has been tested for electrostatic sensitivity to the
limits stated in the specifications. However, NVE recommends that
all integrated circuits be handled with appropriate care to avoid
damage. Damage caused by inappropriate handling or storage could
range from performance degradation to complete failure.
Electromagnetic Compatibility
IsoLoop Isolators have the lowest EMC footprint of any isolation
technology. IsoLoop Isolators’ Wheatstone bridge configuration
and differential magnetic field signaling ensure excellent EMC
performance against all relevant standards.
These isolators are fully compliant with generic EMC standards
EN50081, EN50082-1 and the umbrella line-voltage standard for
Information Technology Equipment (ITE) EN61000. NVE has
completed compliance tests in the categories below:
EN50081-1
Residential, Commercial & Light Industrial
Methods EN55022, EN55014
EN50082-2: Industrial Environment
Methods EN61000-4-2 (ESD), EN61000-4-3 (Electromagnetic
Field Immunity), EN61000-4-4 (Electrical Transient Immunity),
EN61000-4-6 (RFI Immunity), EN61000-4-8 (Power Frequency
Magnetic Field Immunity), EN61000-4-9 (Pulsed Magnetic
Field), EN61000-4-10 (Damped Oscillatory Magnetic Field)
ENV50204
Radiated Field from Digital Telephones (Immunity Test)
Immunity to external magnetic fields is even higher if the field
direction is “end-to-end” rather than to “pin-to-pin” as shown in the
diagram below:
Cross-axis Field Direction
Dynamic Power Consumption
IsoLoop Isolators achieve their low power consumption from the
way they transmit data across the isolation barrier. By detecting the
edge transitions of the input logic signal and converting these to
narrow current pulses, a magnetic field is created around the GMR
Wheatstone bridge. Depending on the direction of the magnetic
field, the bridge causes the output comparator to switch following
the input logic signal. Since the current pulses are narrow, about
2.5 ns, the power consumption is independent of mark-to-space
ratio and solely dependent on frequency. This has obvious
advantages over optocouplers, which have power consumption
heavily dependent on mark-to-space ratio.
Thermal Management
IsoLoop Isolators are designed for low power dissipation and
thermal performance, providing unmatched channel density for
high-performance isolators. Nevertheless, package temperature rise
should be considered when running multiple channels at high
speed. Power consumption is higher at 5 volt operation than at
3.3 volts, and dynamic supply current is higher on the input side of
the isolators than the output side, so thermal management is more
important with five-volt input-side power supplies.
Based on the specifications contained in this datasheet, the derating
curve at typical operating conditions is as follows:
Standard-grade parts have a maximum junction temperature of 110°C.
T-Series parts have a maximum operating junction temperature of
125°C for additional margin at extreme operating conditions.
Power Supply Decoupling
Both power supplies to these devices should be decoupled with low
ESR 47 nF ceramic capacitors. Ground planes for both GND1 and
GND2 are highly recommended for data rates above 10 Mbps.
Capacitors must be located as close as possible to the VDD pins.
Maintaining Creepage
Creepage distances are often critical in isolated circuits. In addition
to meeting JEDEC standards, NVE isolator packages have unique
creepage specifications. Standard pad libraries often extend under
the package, compromising creepage and clearance. Similarly,
ground planes, if used, should be spaced to avoid compromising
clearance. Package drawings and recommended pad layouts are
included in this datasheet.
Signal Status on Start-up and Shut Down
To minimize power dissipation, input signals are differentiated and
then latched on the output side of the isolation barrier to reconstruct
the signal. This could result in an ambiguous output state
depending on power up, shutdown and power loss sequencing.
Therefore, the designer should consider including an initialization
signal in the start-up circuit. Initialization consists of toggling the
input either high then low, or low then high.