AD7864 Analog Devices, AD7864 Datasheet - Page 19

• Manufacturer Part Number: AD7864
• Description: High Speed, Low Power, 4-channel Simultaneous Sampling, 12-Bit ADC
• Manufacturer: Analog Devices

Specifications of AD7864

• Resolution (bits): 12bit
• # Chan: 4
• Sample Rate: 520kSPS
• Interface: Par
• Analog Input Type: SE-Bip,SE-Uni
• Ain Range: Bip 10V,Bip 2.5V,Bip 5.0V,Uni 2.5V,Uni 5.0V
• Adc Architecture: SAR
• Pkg Type: QFP

When reading the output data registers after a conversion
sequence, that is, when BUSY goes low, the register pointer is
incremented on the rising edge of the RD signal, as shown in
Figure 14
the conversion sequence, the pointer is not incremented until a
valid conversion result is in the register to be addressed. In this
case, the pointer is incremented when the conversion has ended
and the result has been transferred to the output data register.
This happens immediately before
. However, when reading the conversion results during
EOC goes low, therefore EOC
*THE POINTER IS NOT INCREMENTED BY A RISING EDGE ON RD UNTIL
RD
CS
THE CONVERSION RESULT IS IN THE OUTPUT DATA REGISTER. THE POINTER
IS RESET WHEN THE LAST CONVERSION RESULT IS READ.
COUNTER
POINTER*
RESET
2-BIT
Figure 14. Output Data Registers
OUTPUT DATA REGISTERS
Rev. D | Page 19 of 28
OE NO. 1
OE NO. 2
OE NO. 3
OE NO. 4
AD7864
NOT VALID
(V
(V
(V
may be used to enable the register contents onto the data bus,
as described in the
Conversion Sequence
Conversion Sequence
to Register 1 on the rising edge of the
conversion result in the sequence is being read. In the example
shown, this means that the pointer is set to Register 1 when the
contents of Register 3 are read.
IN1
IN3
IN4
)
)
)
DRIVERS
OUTPUT
V
DRIVE
OE
DB0 TO DB11
FRSTDATA
Reading Between Each Conversion in the
subsection within the
section. The pointer is reset to point
RD signal when the last
Selecting a
AD7864