Datasheet

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1 Related Documentation from Texas Instruments
2 EVM Overview
2.1 Features
3 Introduction
4 Analog Interface
Related Documentation from Texas Instruments
To obtain a copy of any of the following TI documents, call the Texas Instruments Literature Response
Center at [phone] or the Product Information Center (PIC) at [phone]. When ordering,
identify this booklet by its title and literature number. Updated documents can also be obtained through
our website at www.ti.com.
Data Sheets: Literature Number:
ADS7881 SLAS400
ADS7891 SLAS410
ADS8411 SLAS369
THS4031 SLOS224
OPA132 SBOS054
REF1004-2.5 SBVS032
SN74AHC138 SCLS258
SN74AHC245 SCLS230
SN74AHC1G04 SCLS318
• Full-featured Evaluation Board for the high speed SAR type ADS7881(12-bit 4MSPS) or
ADS7891(14-bit 3MSPS) single channel, parallel interface Analog to Digital Converters.
• On board signal conditioning
• On board Reference
• Input and Output Digital Buffers
• On board decoding for stacking multiple EVMs.
The ADS7881EVM and ADS7891EVM showcase the 12-bit 4-MSPS and 14-bit 3MSPS A-to-D converter.
The ADS7881 and ADS7891 devices include a capacitor based SAR A/D converter with inherent sample
and hold. The two devices offer either a 12-bit or 14-bit parallel interface. Both offer byte mode operation
that enables easy interface with 8-bit processors. They also have a pseudo-differential input stage and a
2.5V internal reference.
This evaluation module serves as a reference design and a low cost method to test these converters in
the users' application. The following sections will describe the pin outs of the various analog, power and
digital connectors and power requirements.
The ADS7881 and ADS7891 analog-to-digital converter has both a positive and negative analog input pin.
The negative input pin, which has a range of -200mV up to 200mV is shorted on the board. A signal for
the positive input pin can be applied at connector P1 pin 2(shown in Table 1 ) or at center pin of SMA
connector J2.
2 SLAU150 – December 2004ADS7881/ADS7891EVM