AD7985 Analog Devices, AD7985 Datasheet - Page 5

• Manufacturer Part Number: AD7985
• Description: 16-Bit, 2.5 MSPS PulSAR 11 mW ADC in QFN
• Manufacturer: Analog Devices

Specifications of AD7985

• Resolution (bits): 16bit
• # Chan: 1
• Sample Rate: 2.5MSPS
• Interface: Ser,SPI
• Analog Input Type: SE-Uni
• Ain Range: (Vref) p-p,Uni (Vref)
• Adc Architecture: SAR
• Pkg Type: CSP

TIMING SPECIFICATIONS
AVDD = DVDD = 2.5 V, BVDD = 5 V, VIO = 1.8 V to 2.7 V, V
Table 4.
Parameter
Conversion Time: CNV Rising Edge
Acquisition Time
Time Between Conversions
CNV Pulse Width
Data Read During Conversion
Quiet Time During Acquisition from Last SCK
SCK Period
SCK Low Time
SCK High Time
SCK Falling Edge to Data Remains Valid
SCK Falling Edge to Data Valid Delay
CNV or SDI Low to SDO D15 MSB Valid
CNV or SDI High or Last SCK Falling Edge
SDI Valid Setup Time from CNV Rising Edge
SDI Valid Hold Time from CNV Rising Edge
SCK Valid Setup Time from CNV Rising Edge
SCK Valid Hold Time from CNV Rising Edge
SDI Valid Setup Time from SCK Falling Edge
SDI Valid Hold Time from SCK Falling Edge
SDI High to SDO High
1
See Figure 2 and Figure 3 for load conditions.
to Data Available
Falling Edge to CNV Rising Edge
to SDO High Impedance
Figure 2. Load Circuit for Digital Interface Timing
TO SDO
20pF
C
L
500µA
500µA
I
I
OL
OH
1.4V
Symbol
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
t
CONV
ACQ
CYC
CNVH
DATA
QUIET
SCK
SCK
SCKL
SCKH
HSDO
DSDO
EN
DIS
SSDICNV
HSDICNV
HSDICNV
SSCKCNV
HSCKCNV
SSDISCK
HSDISCK
DSDOSDI
Rev. A | Page 5 of 28
Test Conditions/Comments
Turbo mode/normal mode
Turbo mode/normal mode
CS mode
Turbo mode/normal mode
CS mode
Chain mode
CS mode
CS mode
Chain mode
Chain mode
Chain mode
Chain mode
Chain mode
Chain mode with busy indicator
REF
= 4.096 V, T
A
1
= −40°C to +85°C, unless otherwise noted.
MINIMUM V
SPECIFICATIONS IN TABLE 3.
90% VIO
t
DELAY
IH
AND MAXIMUM V
Figure 3. Voltage Levels for Timing
Min
80
400/500
10
20
9
11
3.5
3.5
2
4
0
0
5
5
2
3
V
V
IH
IL
1
1
IL
USED. SEE DIGITAL INPUTS
Typ
10% VIO
t
Max
320/420
190/290
4
5
8
15
DELAY
V
V
IH
IL
1
1
1
AD7985
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns