AD7864 High Speed, Low Power, 4-channel Simultaneous Sampling, 12-Bit ADC

The AD7864 is a high speed, low power, 4-channel, simulta-neous sampling 12-bit analog-to-digital converter (ADC) that operates from a single 5 V supply. The part contains a 1.65 μs successive approximation ADC, four track-and-hold amplifiers, a 2.5 V reference, an on-chip clock oscillator, signal conditioning circuitry, and a high speed parallel interface. The input signals on four channels sample simultaneously preserving the relative phase information of the signals on the four analog inputs. The part accepts analog input ranges of ±10 V, ±5 V (AD7864-1), 0 V to +2.5 V, 0 V to +5 V (AD7864-2), and ±2.5 V (AD7864-3).

Any subset of the four channels can be converted to maximize the throughput rate on the selected sequence. Select the channels to convert via hardware (channel select input pins) or software (programming the channel select register).

A single conversion start signal (CONVST) simultaneously places all the track-and-holds into hold and initiates a conversion sequence for the selected channels. The EOC signal indicates the end of each individual conversion in the selected conversion sequence. The BUSY signal indicates the end of the conversion sequence.

Data is read from the part by a 12-bit parallel data bus using the standard CS and RD signals. Maximum throughput for a single channel is 500 kSPS. For all four channels, the maximum throughput is 130 kSPS for the read-during-conversion sequence operation. The throughput rate for the read-after-conversion sequence operation depends on the read cycle time of the processor. See the Timing and Control section. The AD7864 is available in a small (0.3 square inch area) 44-lead MQFP.

Features and Benefits
  • High speed (1.65 μs) 12-bit ADC
  • 4 simultaneously sampled inputs
  • 4 track-and-hold amplifiers
    0.35 μs track-and-hold acquisition time
    1.65 μs conversion time per channel
  • HW/SW select of channel sequence for conversion
  • Single-supply operation
  • Selection of input ranges
    ±10 V, ±5 V for AD7864-1
    ±2.5 V for AD7864-3 0 V to 2.5 V, 0 V to 5 V for AD7864-2
  • High speed parallel interface that allows
    Interfacing to 3 V processors
  • See data sheet for additional features
  • Analog to Digital Converters
    IBIS Models
    Data Sheets
    Documentnote
    AD7864: 4-Channel, Simultaneous Sampling, High Speed, 12-Bit ADC Data Sheet (Rev. D)PDF 413 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    AD7864ASZ-1 Production44 ld MQFP (13.90mm wide)OTH 96-40 to 85C17.8115.19Y
    AD7864ASZ-1REEL Production44 ld MQFP (13.90mm wide)REEL 800-40 to 85C015.19Y
    AD7864ASZ-2 Production44 ld MQFP (13.90mm wide)OTH 96-40 to 85C17.8115.19Y
    AD7864ASZ-2REEL Last Time Buy44 ld MQFP (13.90mm wide)REEL 800-40 to 85C015.19Y
    AD7864ASZ-3 Production44 ld MQFP (13.90mm wide)OTH 96-40 to 85C17.8115.19Y
    AD7864BSZ-1 Production44 ld MQFP (13.90mm wide)OTH 96-40 to 85C23.1619.65Y
    AD7864BSZ-1REEL Production44 ld MQFP (13.90mm wide)REEL 800-40 to 85C019.65Y
    Reference Materials
    AD7864: 4-Channel, Simultaneous Sampling, High Speed, 12-Bit ADC Data Sheet (Rev. D) ad7864
    AD7864 IBIS Model ad7864
    MS-2210:高速ADC的电源设计 ad9861