Application information

RHF1201

12/18

7.3

Reference connection

7.3.1

Internal reference

In the standard configuration, the ADC is biased with the internal reference voltage. The

frequency noise. Refer to Figure 6: Internal reference setting for the schematics.

Figure 6.

Internal reference setting

7.3.2

External reference

It is possible to use an external reference voltage instead of the internal one for specific

applications requiring even better linearity or enhanced temperature behavior. In this case,

the amplitude of the external voltage must be at least equal to the internal one (1.0 V). You

can use an external voltage reference with the configuration shown in Figure 7: External

reference setting to obtain optimum performance.

Figure 7.

External reference setting

This can be very helpful in multichannel applications for example to maintain a good

matching along the sampling frequency range.

RHF1201

VIN

VINB

VREFM

~1V

VREFP

330pF

470nF

10nF

1k

Ω

RHF1201

VIN

VINB

VREFM

VREFP

external

reference

VCCA

330pF

470nF

10nF