Why is isolation need?
Isolators transfer data without a direct electrical connection. Isolation reduces noise, eliminates ground loops, and improves safety.
What are the advantages of IsoLoop Isolators?
The advantages of IsoLoop spintronic GMR isolators are summarized with
the five Bs: Boxes (small packages including MSOPs); Bits (up to
5 channels per device); Baud (up to 150 Mbps and 100 ps jitter); Batteries
(1.5 mA/channel quiescent); and Bullet-proof (up to 6 kVrms isolation;
125°C; unlimited life). This video
What is GMR?
Giant magnetoresistors, where resistance changes
due to conduction electrons scattering at interfaces. The technology is faster, lower power, and more reliable than conventional semiconductors. In awarding the 2007 Nobel Prize in Physics for GMR, the Nobel Committee said,
GMR can be considered one of the first real applications of the promising
field of nanotechnology.
This video has illustrative animations.
What are isolators used for?
Popular applications include RS-485,
Controller Area Network (CAN Bus), isolated
Serial Peripheral Interface (SPI), isolated
A/D converters, isolated
audio, and isolated
Why do folks hate optos?
Optocouplers are big, slow, and unreliable. One of the biggest problems is that LEDs degrade over time. Every photon depletes the LED, so the output decreases and eventually it will fail. IsoLoop isolators use magnetics and spintronics rather than optics. Nothing is depleted.
What types of IsoLoop Isolators are available?
Product lines include
the industry-standard IL700
/ IL200-Series, the IL4-
/ IL3-Series single-chip isolated RS-485/RS-422/PROFIBUS/CAN
cost-effective IL500-Series, and IL600-Series Passive-Input Isolators.
What packages are available?
IsoLoop Isolators are available in MSOP,
0.15" SOIC-16, 0.3"
SOIC-16 and QSOP packages.
What channel configurations are available?
A wide range of channel configurations are available, including one, two, three, four, five, as well as RS-422, RS-485, PROFIBUS, and CAN.
How long is the isolation barrier life?
Other isolators have barriers that degrade over time, but IsoLoop Isolators have a line in the sand barriera patented glass-polymer composite structure that doesnt degrade. Compared to conventional semiconductors, its like indestructible fiberglass versus rusting sheet metal. Reliability data shows failures-in-time of 2.6 per billion hours at 100°C, for an MTBF of 44,000 years. This video explains.
What is the MTBF of NVE isolators?
A remarkable 44,000 years at 100°C. A detailed reliability report is available
What voltage can isolators stand indefinitely?
The maximum voltage indefinitely between the inputs and outputs of an isolator
is called endurance voltage. For most isolators its not specified, but for
NVE isolators, endurance voltage is 1000 Vrms, or 1500 Vpeak or DC.
This video has details.
Whats the difference between baud and hertz?
Two bits of data are transmitted each cycle, so the maximum data rate (baud) is twice the maximum frequency (hertz).
What does useable baud rate mean?
Speed is worthless if its garbled.
Some isolators specify high baud rates but have propagation delays too long to use that baud rate. Others have unrealistic pulse width specifications. NVEs speed specifications support practical use at high speeds, including propagation delay, jitter, and channel-to-channel skew.
What are passive input isolators?
NVE offers both digital-input and passive-input isolators. Passive input isolators have current-mode input coils for flexibility similar to LED-input optocouplers. There is no need for an input-side power supply. Also, NVE passive input isolators are available with either CMOS or open-drain outputs for drop-in optocoupler replacement. Watch this video for specifics.
How much input current do I need to drive a passive
Worst-case is 8 mA, which is for single-ended operation with a 3 V supply.
In differential mode, where the input current reverses, the logic low threshold
current is 5 mA for the range of supplies. A boost capacitor
in parallel with the current-limiting resistor creates current reversals at edge
transitions, reducing the input logic low threshold current to the differential
level of 5 mA.
Can unused inputs be left unconnected?
Some can, but some cant. Inputs with pull-down resistors are noted on the datasheet. Otherwise, unused inputs should be connected to Vdd or GND.
Can power supply decoupling capacitors be larger than recommended?
Yes. NVE recommends 47 nF minimum decoupling capacitors, and many customers use 0.1 µF or larger. The important thing is to use low-ESR ceramic capacitors. A parallel 10 µF tantalum capacitor is also recommended on Vdd2 for bus transceivers.
Are optocouplers good for anything?
Maybe you could use them for geek chic jewelry. Of course, if anyone notices theyre optocouplers, they wont be considered very chic.
How can I try NVE isolators?
Its easy to try its isolators. Distributors such as Digi-Key stock a wide variety. The NVE Online Store has no minimum order and $9.95 flat-rate shipping to North America, and Isolator Evaluation Boards are available to try out a variety of parts.