News

‘ET’ IS BACK!!

We’re happy to announce that the forced retirement of the ‘ET’ prefix in the marking of many of our products, like the ET7272, is ended! The ‘ET’ will, thanks to laser marking’s smaller character fonts, begin to appear again on all ETIC standard product. When we began to offer lead-free product, the identifying ‘LF’ that was added to the marking caused us to take off the ‘ET’ due to space constraints. But with the laser marking, those constraints are no more, and the ‘ET’ will take its place at the head of the part numbers once again.

ET7273C IS COMING…

The ET7273B device will continue to be available for some time, but there is a new rev ‘C’ version coming soon. The only change to the device is to correct a deficiency in the ‘ENABLE’ function. All input and output circuitry, short circuit protection, over-temp protection, and wafer fab processing are unchanged. The schematic change made addresses the rarely used function to ‘disable’ the device.

CUSTOM ENCODER SENSORS…

ETIC continues to provide customers with integrated approaches to satisfy optical encoder configurations for A/B data, index, and commutation tracks. This includes the on-chip interpolation of data for up to 8X (cycles). Base resolutions, without interpolation, of 5000PPR can be achieved in ASICs compatible with a 2 inch diameter encoder. Single or dual track index, and pseudo-differential commutation configurations are common elements of this type of ASIC.

For those preferring to use external interpolation modules, analog (sine/cosine) outputs may be requested in addition to the digitized quadrature outputs normally provided.

Soldering -

Molded (plastic) IC packages are sensitive to rapid changes in ambient temperature, including the thermal shock of reflow soldering. The greatest problem is with the evaporation (and expansion) of moisture in the package cavity, which may cause the body of the device to crack open. This is normally referred to as the popcorn effect.

Particularly sensitive are the thinner packages, such as the TSSOP types. Of course, the degree of thermal shock is a significant factor in controlling the popcorn effect. The higher the temperature, the greater the probability of this phenomenon. Since the lead-free directive also addresses the solder used to mount devices to a PCB, the standard Sn/Pb eutectic solder is being phased out. Replacing it will be a variety of alloys, all of which are likely to require slightly higher reflow temperatures. This will increase the probability of the popcorn effect. To combat this, new mold compounds are formulated to provide greater moisture resistance, and therefore offset the affects of higher reflow temperatures. ETIC has converted to new mold compounds which satisfy both the environmental concerns, (green initiative), and the need for lower sensitivity to moisture.

Devices delivered in the traditional manner, without any form of “dry packaging” to protect against moisture, might require baking immediately prior to soldering. This will eliminate any trapped moisture and prevent damage via the popcorn effect. ETIC can ship devices in a dry pack configuration as an option, at an additional cost.

In all cases, the user is responsible for the effects of subsequent processing on the device. The need for conditioning processes, in order to prevent damage during soldering, should be evaluated by the user. ETIC’s workmanship and construction guarantee will not cover damage which may occur during soldering.