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THS1215

RS

VS+

VS−

RS

RSW

RSW

CI

CI

VCM

VCM

_

+

_

+

R

S t

1

2f

CLK

C

I

In(256)

–R

SW

VIN+

VIN−

R1

R2

−

+

R1

R2

−

+

C1

C1

C2

C2

THS1215

AIN+

AIN−

REFT

REFB

AVDD

2

THS1215

SLAS292A – MARCH 2001 – REVISED MARCH 2004

Figure 16. Simplified Equivalent Input Circuit

To maintain the frequency performance outlined in the specifications, the total source impedance should be

The analog input of the THS1215 is a differential input that can be configured in various ways depending on the

signal source and the required level of performance. A fully differential connection (see Figure 17) delivers the

best performance from the converter.

Figure 17. AC-Coupled Differential Input

The analog input can be dc-coupled (see Figure 18) as long as the inputs are within the analog input common

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