ꢀ ꢁ ꢂꢃ ꢄ ꢃꢃ ꢅ ꢀ ꢁꢂ ꢃ ꢄ ꢃ ꢄ
ꢀ ꢁ ꢂꢃ ꢄ ꢃ ꢆꢅ ꢀ ꢁꢂ ꢃꢄ ꢃ ꢇ
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SBAS323D − JUNE 2004 − REVISED SEPTEMBER 2005
ELECTRICAL CHARACTERISTICS: AVDD = 3V (continued)
3
All specifications from T
to T
, DV
= +2.7V to 5.25V, AV
= +3V, f
= 15.625kHz, PGA = 1, filter = Sinc , Buffer ON, f
= 10Hz, Bipolar, f
= 8MHz,
= 200pF, unless otherwise noted.
MIN
MAX
DD
DD
MOD
DATA
CLK
and V
REF
≡ (REF IN+) − (REF IN−) = +1.25V, unless otherwise noted. For V
, V
= AV , R
DD LOAD
= 10kΩ, and C
LOAD
DAC REF
MSC1211/12/13/14
TYP
PARAMETER
CONDITIONS
MIN
MAX
UNITS
ADC Offset DAC
Offset DAC Range
Bipolar Mode
V
/(2•PGA)
V
REF
Offset DAC Monotonicity
Offset DAC Gain Error
Offset DAC Gain Error Drift
8
Bits
1.5
1
% of Range
ppm/°C
System Performance
Resolution
24
24
Bits
Bits
ENOB
22
Output Noise
See Typical Characteristics
3
No Missing Codes
Integral Nonlinearity
Offset Error
Sinc Filter
Bits
%FSR
ppm of FS
ppm of FS/°C
%
End Point Fit, Bipolar Mode
After Calibration
3
0.0015
3.5
(2)
Offset Drift
Before Calibration
After Calibration
0.001
−0.002
1.0
(3)
Gain Error
(2)
Gain Error Drift
Before Calibration
ppm/°C
% of FS
% of FS
dB
System Gain Calibration Range
System Offset Calibration Range
80
120
50
−50
At DC
115
130
120
120
100
100
92
f
f
f
f
f
= 60Hz, f
= 50Hz, f
= 60Hz, f
= 10Hz
= 50Hz
= 60Hz
= 50Hz
= 60Hz
dB
CM
CM
CM
SIG
SIG
DATA
DATA
DATA
Common-Mode Rejection
dB
dB
= 50Hz, f
= 60Hz, f
dB
DATA
Normal Mode Rejection
dB
DATA
(4)
Power-Supply Rejection
Voltage Reference Inputs
Reference Input Range
At DC, dB = −20log(∆VOUT/∆V
)
dB
DD
(3)
DD
REF IN+, REF IN−
AGND
0.1
AV
V
V
V
V
≡ (REF IN+) − (REF IN−)
1.25
110
3
AV
DD
V
REF
REF
At DC
Common-Mode Rejection
(5)
dB
µA
kΩ
REF
Input Current
V
= 1.25V, ADC Only
REF
DAC Reference Input Resistance
For Each DAC, PGA = 1
20
On-Chip Voltage Reference
Output Voltage
VREFH = 0 at +25°C, REFCLK = 250kHz
1.245
1.25
1.255
V
Power-Supply Rejection Ratio
Short-Circuit Current Source
Short-Circuit Current Sink
Short-Circuit Duration
Drift
65
dB
mA
µA
2.6
50
Sink or Source
Indefinite
5
3
ppm/°C
Ω
Output Impedance
Sourcing 100µA
CREFOUT = 0.1µF
Buffer ON, T = +25°C
Buffer ON
Startup Time from Power ON
Temperature Sensor Voltage
Temperature Sensor Coefficient
8
ms
115
375
mV
µV/°C
(1)
The input impedance for PGA = 128 is the same as that for PGA = 64 (that is, 7MΩ/64).
(2)
(3)
(4)
(5)
(6)
(7)
(8)
Calibration can minimize these errors.
The gain calibration cannot have a REF IN+ of more than AV
−1.5V with Buffer ON. To calibrate gain, turn Buffer OFF.
DD
∆V
OUT
is change in digital result.
9pF switched capacitor at f
clock frequency (see Figure 14).
SAMP
Linearity calculated using a reduced code range of 512 to 65024; output unloaded.
Ensured by design and characterization; not production tested.
Analog Brownout Detect OFF (HCR1.3 = 1), Analog LVD OFF (LVDCON.7 = 1).
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