TLE2027, TLE2037, TLE2027A, TLE2037A, TLE2027Y, TLE2037Y

EXCALIBUR LOW-NOISE HIGH-SPEED

PRECISION OPERATIONAL AMPLIFIERS

SLOS192 – FEBRUARY 1997

6–15

POST OFFICE BOX 655303

typical values

Typical values presented in this data sheet represent the median (50% point) of device parametric performance.

initial estimates of parameter distributions

In the ongoing program of improving data sheets and supplying more information to our customers, Texas

Instruments has added an estimate of not only the typical values but also the spread around these values. These

are in the form of distribution bars that show the 95% (upper) points and the 5% (lower) points from the

characterization of the initial wafer lots of this new device type (see Figure 5). The distribution bars are shown

at the points where data was actually collected. The 95% and 5% points are used instead of

± 3 sigma since

some of the distributions are not true Gaussian distributions.

The number of units tested and the number of different wafer lots used are on all of the graphs where distribution

bars are shown. As noted in Figure 5, there were a total of 835 units from two wafer lots. In this case, there is

a good estimate for the within-lot variability and a possibly poor estimate of the lot-to-lot variability. This is always

the case on newly released products since there can only be data available from a few wafer lots.

The distribution bars are not intended to replace the minimum and maximum limits in the electrical tables. Each

distribution bar represents 90% of the total units tested at a specific temperature. While 10% of the units tested

fell outside any given distribution bar, this should not be interpreted to mean that the same individual devices

fell outside every distribution bar.

4.5

5

4

3.5

3

2.5

150

125

100

75

50

25

0

–25

–50

–75

(5% of the devices fell below this point.)

5% point on the distribution bar

and lower points on the distribution bar.

90% of the devices were within the upper

(5% of the devices fell above this point.)

95% point on the distribution bar

SUPPLY CURRENT

vs

FREE-AIR TEMPERATURE

VCC

VO = 0

No Load

Sample Size = 835 Units

From 2 Water Lots

Figure 5. Sample Graph With Distribution Bars