c) Total output-referred noise voltage is shown by the

The MAX4100/MAX4101, with two high-impedance inputs,

have low 8nV

√Hz voltage noise and only 0.8pA√Hz current

noise.

An example of DC error calculations, using the

MAX4100/MAX4101 typical data and the typical operating

Calculating total output-referred noise in a similar man-

ner yields:

With a 200MHz system bandwidth, this calculates to

In both DC and noise calculations, errors are dominat-

ed by offset voltage and noise voltage (rather than by

input bias current or noise current).

Metal-film resistors with leads are manufactured using

a thin-film process, where resistive material is deposit-

ed in a spiral layer around a ceramic rod. Although the

materials used are noninductive, the spiral winding pre-

sents a small inductance (about 5nH) that may have an

adverse effect on high-frequency circuits.

e

enV

Hz

n OUT

n OUT

()

()

.

/

=+

×







 +×









=

−−

1 1

2 0 810

100

810

8

12

2

9

2

VI

R

V

R

R

V

VmV

OUT

OS S

OS

F

G

OUT

OUT

=+









=×

×

+ ×









+

()

=

−−

.

1

310

10

1 10

1 1

26

62

3

e

R

R

iR

e

n OUT

F

G

nS

N







+

()

12

22

500MHz, Low-Power Op Amps

10

______________________________________________________________________________________

Figure 4a. MAX4100 Bandwidth vs. Capacitive Load

10

8

4

0

-4

-8

-10

0.1M

1M

10M

100M

1G

-6

FREQUENCY (Hz)

-2

2

6

10

8

4

0

-4

-8

-10

0.1M

1M

10M

100M

1G

-6

FREQUENCY (Hz)

-2

2

6

Figure 4b. MAX4100 Bandwidth vs. Capacitive Load and

Isolation Resistor

MAX4100

MAX4101

MAX4100

MAX4101

Figure 3. Output Offset Voltage