LTC6652AHMS8-1.25-PBF LINER [Linear Technology], LTC6652AHMS8-1.25-PBF Datasheet - Page 13

• Manufacturer Part Number: LTC6652AHMS8-1.25-PBF
• Description: Precision Low Drift Low Noise Buffered Reference
• Manufacturer: LINER [Linear Technology]

applications inForMation
Long-Term Drift
Long-term drift cannot be extrapolated from accelerated
high temperature testing. This erroneous technique gives
drift numbers that are wildly optimistic. The only way
long-term drift can be determined is to measure it over
the time interval of interest. The LTC6652 long-term drift
data was collected on more than 100 parts that were sol-
dered into PC boards similar to a “real world” application.
The boards were then placed into a constant temperature
oven with T
and measured with an 8.5 digit DVM. Long-term drift is
shown below in Figure 12.
Figure 13a. MS8 Hysteresis Plot –40°C to 125°C
–20
–40
35
30
25
20
15
10
A
80
60
40
20
5
0
–250
0
= 35°C, their outputs were scanned regularly
0
Figure 12a. MS8 Long-Term Drift
LTC6652-2.5 MS8 PACKAGE
3 TYPICAL PARTS
T
A
= 35°C
125°C TO 25°C
–150
300
DISTRIBUTION (ppm)
600
–50
HOURS
900
50
–40°C TO 25°C
1200
150
6652 F13a
6652 F12a
1500
Hysteresis
The hysteresis data shown in Figure 13 represents the
worst-case data collected on parts from –40°C to 125°C.
The output is capable of dissipating relatively high power,
i.e., for the LT6652-2.5, P
The thermal resistance of the MS8 package is 200°C/W
and this dissipation causes a 11.8°C internal rise. This
could increase the junction temperature above 125°C and
may cause the output to shift due to thermal hysteresis.
Figure 13b. LS8 Hysteresis Plot –40°C to 125°C
–20
–40
18
16
14
12
10
80
60
40
20
8
6
4
2
0
–150 –110 –70 –30 0
0
0
LTC6652-2.5 LS8 PACKAGE
4 TYPICAL PARTS
T
Figure 12b. LS8 Long-Term Drift
A
= 30°C
200
DISTRIBUTION (ppm)
400
D
HOURS
= 10.7V • 5.5mA = 58.85mW.
600
30
70
800
110
6652 F13b
6652 F12b
LTC6652
1000
150
13
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