REF102

®

7

FIGURE 4. REF102 Optional Output Voltage Fine Adjust.

Higher resolution, reduced range (typically

±25mV).

APPLICATIONS INFORMATION

High accuracy, extremely low drift, outstanding stability,

and low cost make the REF102 an ideal choice for all

instrumentation and system reference applications. Figures 6

through 14 show a variety of useful application circuits.

FIGURE 6. –10V Reference Using a) Resistor or b) OPA27.

See AB-004 for more detail

1.4mA < (5V –I

R

S

OPTIONAL NOISE REDUCTION

The high-frequency noise of the REF102 is dominated by

the zener diode noise. This noise can be greatly reduced by

connecting a capacitor between the Noise Reduction pin and

to the figure on the first page of the data sheet) and attenu-

ates the high-frequency noise generated by the zener. Figure

5 shows the effect of a 1

µF noise reduction capacitor on the

the filter has a –3dB frequency of about 22Hz. The result is

a reduction in noise from about 800

µVp-p to under 200µ

Vp-p. If further noise reduction is required, use the circuit in

Figure 14.

FIGURE 5. Effect of 1

µF Noise Reduction Capacitor on

6

b) Precision –10V Reference.

a) Resister Biased –10V Reference

R

S

I

L

4

REF102

2

–10V Out

V+ (1.4V to 26V)

2

6

4

10V

OPA27

R

1

2k

Ω

C

1000pF

1

–10V Out

–15V

REF102

V+ (1.4V to 26V)

REF102

V+

2

4

20k

Output

Voltage

Adjust

Ω

+10V

5

V

TRIM

6

V

OUT

R

S

1M

Ω

1µF

Tantalum

+