Datasheet

LT1460
18
1460fc
Table 1. Maximum Output Capacitance for LT1460S3
VOLTAGE
OPTION I
OUT
= 100µA I
OUT
= 1mA I
OUT
= 10mA I
OUT
= 20mA
2.5V >10µF >10µF 2µF 0.68µF
3V >10µF >10µF 2µF 0.68µF
3.3V >10µF >10µF 1µF 0.68µF
5V >10µF >10µF 1µF 0.68µF
10V >10µF 1µF 0.15µF 0.1µF
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 LT1460S3 long-term
drift data was taken on over 100 parts that were soldered
into PC boards similar to a “real world” application. The
boards were then placed into a constant temperature oven
with T
A
= 30°C, their outputs were scanned regularly and
measured with an 8.5 digit DVM. Figure 16 shows typical
long-term drift of the LT1460S3s.
Hysteresis
Hysteresis data shown in Figure 17 and Figure 18 represents
the worst-case data taken on parts from 0°C to 70°C and
from –40°C to 85°C. The device is capable of dissipating
relatively high power, i.e., for the LT1460S3-2.5, PD = 17.5V
• 20mA = 350mW. The thermal resistance of the SOT-23
package is 325°C/W and this dissipation causes a 114°C
internal rise producing a junction temperature of T
J
= 25°C
+ 114°C = 139°C. This elevated temperature will cause
the output to shift due to thermal hysteresis. For highest
performance in precision applications, do not let the
LT1460S3’s junction temperature exceed 85°C.
Figure 16. Typical Long-Term Drift
Figure 17. 0°C to 70°C Hysteresis
Figure 18. –40°C to 85°C Hysteresis
HOURS
–150
ppm
–50
50
150
–100
0
100
200 400 600 800
1460 F16
10001000 300 500 700 900
HYSTERESIS (ppm)
–240 –160 –80 0
NUMBER OF UNITS
8
70°C TO 25°C 0°C TO 25°C
10
12
1460 F17
6
4
80
160
–200 –120 –40 40
120
200
2
0
18
16
14
240
WORST-CASE HYSTERESIS
ON 40 UNITS
HYSTERESIS (ppm)
–600 –400 –200 0
NUMBER OF UNITS
4
85°C TO 25°C –40°C TO 25°C
5
6
1460 F18
3
2
200
400
–500 –300 –100 100
300
500
1
0
9
8
7
600
WORST-CASE HYSTERESIS
ON 34 UNITS
applications inForMation