Digital is not everything: in real life, one sometimes needs a comparator. Texas Instruments recently-introduced TLV70x1 series provide a cheap and space-conscious solution for this problem.

The traditional knee-jerk reaction to a problem requiring a comparator is a great indicator of your age: some will grab an LM324, others will go for an LM741. Both of these are opamps, which require quite a bit of external “diddling” before they can act as a reliable comparator.

This not only increases BOM size and cost, but also wastes space on the board.

Go dedicated

TI’s TLV70x1 family is a set of four ICs, each of which contain but ONE comparator. The most outstanding attribute is the small size: the Extra Small Outline No-Lead (aka X2SON) package, described here, is but 0.8×0.8mm small.

For prototyping, a classic SOT23 case is also available, which can be soldered by hand with some practice.

BOM changes

Generally, the parts are optimized to limit BOM changes.

First of all, a supply voltage range of 1.6V to 5.5V means that the chip is very likely to “blend into” your environment.

Benefit number two is an internal hysteresis to the – temperature dependent – tune of 4mV, thereby eliminating the need for a feedback resistor.

One ambivalent aspect of the TLV70xx family is their capability to drive and sink insane amounts of current. Short-circuit values are in the range of 50mA, which means that most LEDs and even longer PCB traces can be driven directly.

Of course, this also means that a bypass capacitor is recommended – the knife cuts both ways.

Greetings from the family

Traditionally, small part number deviations meant a change in the amount of chips in the case. This is not the case for the TLV family: the TLV7011 and 7031 have push-pull outputs, while the other ones use the open-drain principle.

Furthermore, TLV7011 and 7021 use 5 Microamps of current and offer a propagation delay of 260ns, while the 7031 and 7041 need 335 Nanoamps at 3 Microseconds of propagation.

Be aware that the TLV70xx series, being quite young, shows a tremendous price spread: as of this writing, quantity one prices range from 17 to more than 50 cents. Furthermore, finding datasheets can be difficult. But, as always, OEMsecrets to the rescue – simply follow the links below for more comparator goodness!

Part:
TLV7011

Datasheet:
http://www.ti.com/product/tlv7011?HQS=corp-tistore-null-storeinv-invf-store-oemsecrets-wwe

OEMSecrets link:
https://www.oemsecrets.com/search.php?partNo=TLV7011DPWR

Ing. Tam Hanna…has worked in the embedded space since the time when the PIC 16F84A was hot. After a few years of mobile computing, his consulting company Tamoggemon Holding k.s. has refocused on hardware design.

OEMsecrets is a leading price comparison search site for electronic parts, listing over 32 million products from 120 distributors. The website is free to use for all engineers and buyers, allowing users to quickly and easily compare distributor prices and availability.