SBAS367F
–
JUNE 2007
–
REVISED FEBRUARY 2011
ELECTRICAL CHARACTERISTICS (continued)
All specifications at T
A
=
–
40
°
C to +105
°
C, AVDD = +5V, DVDD = +1.8V, IOVDD = +3.3V, f
CLK
= 27MHz, VREFP = 2.5V,
VREFN = 0V, and all channels active, unless otherwise noted.
ADS1274, ADS1278
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
AC PERFORMANCE
Crosstalk
f = 1kHz,
–
0.5dBFS
(5)
–
107
dB
High-Speed mode
101
106
dB
V
REF
= 2.5V
103
110
dB
High-Resolution mode
Signal-to-noise ratio (SNR)
(6)
V
REF
= 3V
111
dB
(unweighted)
Low-Power mode
101
106
dB
Low-Speed mode
101
107
dB
Total harmonic distortion (THD)
(7)
V
IN
= 1kHz,
–
0.5dBFS
–
108
–
96
dB
Spurious-free dynamic range
109
dB
Passband ripple
±
0.005
dB
Passband
0.453 f
DATA
Hz
–
3dB Bandwidth
0.49 f
DATA
Hz
High-Resolution mode
95
dB
Stop band attenuation
All other modes
100
High-Resolution mode
0.547 f
DATA
127.453 f
DATA
Hz
Stop band
All other modes
0.547 f
DATA
63.453 f
DATA
Hz
High-Resolution mode
39/f
DATA
s
Group delay
All other modes
38/f
DATA
s
High-Resolution mode
Complete settling
78/f
DATA
s
Settling time (latency)
All other modes
Complete settling
76/f
DATA
s
VOLTAGE REFERENCE INPUTS
Negative reference input (VREFN)
AGND
–
0.1
AGND + 0.1
V
0.1
≤
f
CLK
≤
27MHz
0.5
2.5
3.1
V
Reference input voltage (V
REF
)
(8)
27
<
f
CLK
≤
32.768MHz
0.5
2.5
2.6
V
(V
REF
= VREFP
–
VREFN)
32.768MHz
<
f
CLK
≤
37MHz
0.5
2.048
2.1
V
High-Speed mode
1.3
k
Ω
High-Resolution mode
1.3
k
Ω
ADS1274
Reference Input impedance
Low-Power mode
2.6
k
Ω
Low-Speed mode
13
k
Ω
High-Speed mode
0.65
k
Ω
High-Resolution mode
0.65
k
Ω
ADS1278
Reference Input impedance
Low-Power mode
1.3
k
Ω
Low-Speed mode
6.5
k
Ω
DIGITAL INPUT/OUTPUT (IOVDD = 1.8V to 3.6V)
V
IH
0.7 IOVDD
IOVDD
V
V
IL
DGND
0.3 IOVDD
V
V
OH
I
OH
= 4mA
0.8 IOVDD
IOVDD
V
V
OL
I
OL
= 4mA
DGND
0.2 IOVDD
V
Input leakage
0
<
V
IN DIGITAL
<
IOVDD
±
10
μ
A
High-Speed mode
(8)
0.1
37
MHz
Master clock rate (f
CLK
)
Other modes
0.1
27
MHz
(5)
Worst-case channel crosstalk between one or more channels.
(6)
Minimum SNR is ensured by the limit of the DC noise specification.
(7)
THD includes the first nine harmonics of the input signal; Low-Speed mode includes the first five harmonics.
(8)
f
CLK
= 37MHz max for High-Speed mode, and 27MHz max for all other modes. See
for V
REF
restrictions in High-Speed mode.
4
©
2007
–
2011, Texas Instruments Incorporated
Product Folder Link(s):