REF102

6

SBVS022B

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INSTALLATION AND

OPERATING INSTRUCTIONS

BASIC CIRCUIT CONNECTION

Figure 2 shows the proper connection of the REF102. To

achieve the specified performance, pay careful attention to

layout. A low resistance star configuration will reduce voltage

errors, noise pickup, and noise coupled from the power

supply. Commons should be connected as indicated, being

sure to minimize interconnection resistances.

OPTIONAL OUTPUT VOLTAGE ADJUSTMENT

Optional output voltage adjustment circuits are shown in

Figures 3 and 4. Trimming the output voltage will change the

voltage drift by approximately 0.008ppm/

°C per mV of trimmed

voltage. In the circuit in Figure 3, any mismatch in TCR

between the two sections of the potentiometer will also affect

drift, but the effect of the

∆TCR is reduced by a factor of five

by the internal resistor divider. A high quality potentiometer,

with good mechanical stability, such as a cermet, should be

REF102

1

µF

Tantalum

+

R

L 1

R

L 2

R

L 3

V+

(1)

2

(2)

(2)

(1)

4

6

NOTES: (1) Lead resistances here of up to a few ohms have

negligible effect on performance. (2) A resistance of 0.1

Ω in

series with these leads will cause a 1mV error when the load

current is at its maximum of 10mA. This results in a 0.01%

error of 10V.

FIGURE 2. REF102 Installation.

REF102

1

µF

Tantalum

+

V+

2

4

20k

Output

Voltage

Adjust

Minimum range (

±300mV) and minimal

degradation of drift.

Ω

+10V

5

V

TRIM

6

V

OUT

FIGURE 3. REF102 Optional Output Voltage Adjust.

REF102

V+

2

4

20k

Output

Voltage

Adjust

Higher resolution, reduced range (typically

±25mV).

Ω

+10V

5

V

TRIM

6

V

OUT

R

S

1M

Ω

1

µF

Tantalum

+

FIGURE 4. REF102 Optional Output Voltage, Fine Adjust.

used. The circuit in Figure 3 has a minimum trim range of

±300mV. The circuit in Figure 4 has less range but provides

higher resolution. The mismatch in TCR between RS and the

internal resistors can introduce some slight drift. This effect

is minimized if RS is kept significantly larger than the 50kΩ

internal resistor. A TCR of 100ppm/

°C is normally sufficient.