AD7656-1 Analog Devices, AD7656-1 Datasheet - Page 26

• Manufacturer Part Number: AD7656-1
• Description: 250 kSPS, 6-Channel, Simultaneous Sampling, Bipolar 16-Bit ADC
• Manufacturer: Analog Devices

Specifications of AD7656-1

• Resolution (bits): 16bit
• # Chan: 6
• Sample Rate: 250kSPS
• Interface: Par,Ser,SPI
• Analog Input Type: SE-Bip
• Ain Range: 10V p-p,20 V p-p,Bip 10V,Bip 5.0V
• Adc Architecture: SAR
• Pkg Type: QFP

AD7656-1/AD7657-1/AD7658-1
The first bit of the conversion result is valid on the first SCLK
falling edge after the CS falling edge. The subsequent 15 data
bits are clocked out on the rising edge of the SCLK signal. Data
is valid on the SCLK falling edge. To access each conversion result,
CONVST A,
CONVST B,
CONVST C
DOUT A,
DOUT B,
DOUT C
BUSY
CS
SCLK
ACQUISITION
CONVST A,
CONVST B,
CONVST C
DOUT A
DOUT B
DOUT C
DOUT A
DOUT B
BUSY
SCLK
CS
SCLK
CS
t
1
CONVERSION
t
CONV
t
CONV
t
2
t
16
DB15
Figure 32. Serial Interface with Three DOUT Lines
Figure 33. Serial Interface with Two DOUT Lines
t
17
Figure 34. Serial Read Operation
V1
V3
DB14
V1
V3
V5
Rev. C | Page 26 of 32
t
19
DB13
16
t
18
V2
V4
16 clock pulses must be provided to the AD7656-1/AD7657-1/
AD7658-1.
access the conversion results.
ACQUISITION
t
ACQ
t
ACQ
Figure 34
V2
V4
V6
V5
V6
DB1
shows how a 16-SCLK read is used to
t
20
32
48
DB0
t
QUIET
t
21
t
QUIET
t
10