“Typical”—what does it mean in a data sheet specification?

RE: “Typical”—what does it mean in a data sheet specification?

Ken Dillinger — Thu, 18 Oct 2012 02:13:50 GMT

In all my years of reading op-amp datasheets I found that many, if not all, dynamic specifications (noise, GBWP, Gain/Phase margin, SR, THD+N anything vs. Frequency, etc.) are presented as typical values. On top of a typical value, it is usually only stated to be at room temperature - so what happens at cold and hot temperatures? Since the tail current drives most of these I presume a good rule of thumb would be /2 and x2 at cold and hot respectively. When you design ULTRA LOOOOWWW POOOWEEEERRR!!!! circuits, I tell ya, the customer wants every nA saved. Yikes!

This is a good write up since these gems lie buried in the minds of designers.

-Ken

RE: “Typical”—what does it mean in a data sheet specification?

Bruce Trump — Tue, 19 Jun 2012 17:16:39 GMT

John-- I'm a long distance literally and figuratively from the MSP430 product line so I can't comment with authority. The practice of offering various versions of a device with different tested limits and price points is very common in the IC business. Testing and assuring performance limits has real costs and we often provide more than one version to meet differing needs.

Thanks for your example and comment. Regards, Bruce.

RE: “Typical”—what does it mean in a data sheet specification?

John Davies — Tue, 19 Jun 2012 13:37:58 GMT

It's a quite different system, but the difference between the F2xx and G2xx series of MSP430 devices is an interesting example of typical values compared with limits. Some G2xx devices appear to offer identical features to F2xx devices but the price of the corresponidng G2xx is lower. Many of the parameters are given only as 'typical' values for the G2xx but have limits for F2xx. I assume that this lowers the testing costs for the G2xx because the limits do not need to be checked.