AD7825

a 3 V/5 V, 2 MSPS, 8-Bit, 1-, 4-, 8-Channel Sampling ADCs AD7822/AD7825/AD7829 FUNCTIONAL BLOCK DIAGRAM CONVST EOC A0* A1* A2* PD* VDD FEATURES 8-Bit Half-Flash ADC with 420 ns Conversion Time 1, 4 and 8 Single-Ended Analog Input Channels Available with Input Offset Adjust On-Chip Track-and-Hold SNR Performance Given for Input Frequencies Up to 10 MHz On-Chip Reference (2.5 V) Automatic Power-Down at the End of Conversion Wide Operating Supply Range 3 V ؎ 10% and 5 V ؎ 10% Input Ranges 0 V to 2 V p-p, VDD = 3 V ؎ 10% 0 V to 2.5 V p-p, V DD = 5 V ؎ 10% Flexible Parallel Interface with EOC Pulse to Allow Stand-Alone Operation APPLICATIONS Data Acquisition Systems, DSP Front Ends Disk Drives Mobile Communication Systems, Subsampling Applications GENERAL DESCRIPTION CONTROL LOGIC COMP 2.5V REF VIN1 VIN2* VIN3* VIN4* VIN5* VIN6* VIN7* VIN8* BUF VREFIN/REFOUT INPUT MUX T/H 8-BIT HALF FLASH ADC DB7 PARALLEL PORT DB0 VMID *A0, A1 *A2 *PD *VIN2 TO VIN4 *VIN4 TO VIN8 AGND DGND CS RD AD7825/AD7829 AD7829 AD7822/AD7825 AD7825/AD7829 AD7829 The AD7822, AD7825, and AD7829 are high speed, 1-, 4-, and 8-channel, microprocessor-compatible, 8-bit analog-to-digital converters with a maximum throughput of 2 MSPS. The AD7822, AD7825, and AD7829 contain an on-chip reference of 2.5 V (2% tolerance), a track/hold amplifier, a 420 ns 8-bit half-flash ADC and a high speed parallel interface. The converters can operate from a single 3 V ± 10% and 5 V ± 10% supply. The AD7822, AD7825, ...