REF50 datasheet(28/52 Pages) TI2

28 / 52 page

9 Applications and Implementation

Note

Information in the following applications sections is not part of the TI component specification,

and TI does not warrant its accuracy or completeness. TI’s customers are responsible for

determining suitability of components for their purposes, as well as validating and testing their design

implementation to confirm system functionality.

9.1 Application Information

Data acquisition systems often require stable voltage references to maintain accuracy. The REF50xx family

features low noise, very low drift, and high initial accuracy for high-performance data converters. Figure 9-1

shows the REF5040 in a basic data acquisition system.

9.2 Typical Applications

9.2.1 16-bit, 250KSPS Data Acquisition System

ADS8326

REF5040

OPA365

ESR

47µF

10µF

REFIN

CLK

SDO

1nF

0-4V

124Ÿ

Figure 9-1. Complete Data Acquisition System Using the REF50xx

9.2.1.1 Design Requirements

When using the REF50xx in the design, select a proper output capacitor that does not create gain peaking,

thereby increasing total system noise. At the same time, select a capacitor that provides the required filtering

performance for the system. Add input bypass capacitor and noise reduction capacitors for peak performances.

During the design of the data acquisition system, give equal consideration to the buffering analog input signal

and the reference voltage. Having a properly designed input buffer with an associated RC filter is a necessary

requirement for good performance of the data acquisition system.

9.2.1.2 Detailed Design Procedure

The OPA365 is used to drive the 16-bit analog-to-digital converter (ADS8326). The RC filter at the output of the

OPA365 is used to reduce the charge kick-back created by the opening and closing of the sampling switch inside

the ADC. Design the RC filter such that the voltage at the sampling capacitor settles to 16-bit accuracy within

the acquisition time of the ADC. Verify that the bandwidth of the driving amplifier is at least be four times the

bandwidth of the RC filter.

The REF5040 is used to drive the REF pin of the ADS8326. Proper selection of voltage reference output

capacitor is very important for this design. Very low equivalent series resistance (ESR) creates gain-peaking,

REF50, REF50E

SBOS410O – JUNE 2007 – REVISED OCTOBER 2025

www.ti.com

Submit Document Feedback

Product Folder Links: REF50 REF50E

REF50 数据表(PDF) 28 Page - Texas Instruments

REF50 数据表(HTML) 28 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

数据表下载