描述The ADS7891 is a 14-bit 3-MSPS A-to-D converter with 2.5-V internal reference. The device includes acapacitor based SAR A/D converter with inherent sample and hold. The device offers a 14-bit parallel interfacewith an additional byte mode that provides easy interface with 8-bit processors. The device has apseudo-differential input stage. The ?IN swing of ±200 mV is useful to compensate for ground voltage mismatch between the ADC and sensorand also to cancel common-mode noise. With nap mode enabled, the device operates at lower power whenused at lower conversion rates. The device is available in a 48-pin TQFP package.特性3 MHz Sample Rate, 14-Bit Resolution Zero Latency Unipolar, Pseudo Differential Input, Range: 0 V to 2.5 V High Speed Parallel Interface 78 dB SNR and 88.5 dB THD at 3 MSPS Power Dissipation 85 mW at 3 MSPS Nap Mode (10 mW Power Dissipation) Power Down (10 μW) Internal Reference Internal Reference Buffer 8-/14-Bit Bus Transfer 48-Pin TQFP Package APPLICATIONS Optical Networking (DWDM, MEMS Based Switching) Spectrum Analyzers High Speed Data Acquisition Systems High Speed Close-Loop Systems Telecommunication Ultra-Sound Detection