LT1027LS8

8

1027ls8f

For more information www.linear.com/LT1027LS8

applicaTions inForMaTion

The circuits in Figure 2 and Figure 3 illustrate proper con-

nections to minimize errors due to ground loops and line

losses. Losses in the output lead can be further reduced

by adding a PNP boost transistor if load current is 5mA

or higher. R2 can be added to further reduce current in

the output sense load.

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 LT1027LS8 long-term drift data was collected on 80

parts that were soldered into printed circuit boards similar

to a real world application. The boards were then placed

outputs were scanned regularly and measured with an 8.5

digit DVM. Typical long-term drift is illustrated in Figure 4.

HOURS

0

20

80

100

1500

1027LS8 F04

–20

–80

0

40

60

–40

–60

–100

500

1000

2500

2000

3000

Figure 2. Standard Connection

Figure 3. Driving Higher Load Currents

IN

OUT

GND

+

GROUND

RETURN

KEEP THIS LINE RESISTANCE LOW

1027LS8 F02

INPUT

LT1027LS8

LOAD

IN

OUT

GND

LT1027LS8

GROUND

RETURN

INPUT

R1

91

R2*

2.4k

LOAD

1027LS8 F03

*OPTIONAL–REDUCES CURRENT IN OUTPUT SENSE LEAD

4.7µF

+

2N4403

Figure 4. Long-Term Drift