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LOG102

12

SBOS211A

(10)

(11)

(12)

(13)

(14)

(15)

≈+

+

1 003

10

10

0 004

0 003

6

7

.

log

.

.

–

–

= 1.003 (1) + 0.004 + 0.0003

= 1.0073V

Since the ideal output is 1.000V, the error as a percent of

reading is

%

.

%.

%

error

=•

=

0 0073

1

100

0 73

For the case of voltage inputs, the actual transfer function is

VV

K

V

R

I

E

R

V

R

I

E

R

Nn

V

OUT

B

OS

B

OS

OS OUT

=

(

)

±

±

±±

11

2

1

1

1

1

1

2

2

2

2

2

∆ log

–

–

Where

E

R

and

E

R

OS

OS

1

1

2

2

are considered to be zero for large

values of resistance from external input current sources.