DDC118_16 Datasheet, PDF (3/36 Pages) Texas Instruments – Octal Current Input, 20-Bit Analog-To-Digital Converter

DDC118
www.ti.com
SBAS325B − JUNE 2004 − REVISED APRIL 2009
ELECTRICAL CHARACTERISTICS
At TA = +25°C, AVDD = +5V, DVDD = 3V, VREF = +4.096V, Range 5 (250pC), and continuous mode operation, unless otherwise noted.
Low-Power Mode: TINT = 400µs and CLK = 4MHz; High-Speed Mode: TINT = 320µs and CLK = 4.8MHz.
Low-Power Mode
High-Speed Mode
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
MIN TYP MAX
UNITS
ANALOG INPUT RANGE
Range 0
Range 1
Range 2
Range 3
Range 4
Range 5
Range 6
Range 7
Negative Full-Scale Range
Input Current⁽²⁾
10.2
12
13.8
∗⁽¹⁾ ∗
∗
pC
47.5
50
52.5
∗∗∗
pC
95
100
105
∗∗∗
pC
142.5
150
157.5
∗∗∗
pC
190
200
210
∗∗∗
pC
237.5
250
262.5
∗∗∗
pC
285
300
315
∗∗∗
pC
332.5
350
367.5
∗∗∗
pC
−0.4% of Positive Full-Scale Range
∗
pC
750
∗
µA
DYNAMIC CHARACTERISTICS
Data Rate
Integration Time, T_INT
System Clock Input (CLK)
CLK_4X = 0
CLK_4X = 1
Data Clock (DCLK)
Continuous Mode
400
Non-continuous Mode, Range 1 to 7
50
2.5
1,000,000 320
∗
4
16
16
3.125
∗
4.8
19.2
∗
kSPS
µS
µS
MHz
MHz
MHz
ACCURACY
Noise, Low-Level Input⁽³⁾
Integral Linearity Error⁽⁶⁾
Resolution
Input Bias Current
Range Error Match⁽⁷⁾
Range Sensitivity to VREF
Offset Error
Offset Error Match⁽⁷⁾
DC Bias Voltage⁽⁹⁾
Power-Supply Rejection Ratio
Internal Test Signal
Internal Test Accuracy
C_SENSOR(4) = 50pF, Range 5 (250pC)
FORMAT = 1
FORMAT = 0
All Ranges
V_REF = 4.096 ± 0.1V
Range 5 (250pC)
Low-Level Input (< 1% FSR)
at dc
5.2
6.5
±0.01% Reading ± 0.5ppm FSR, typ
±0.025% Reading ± 1.0ppm FSR, max
20
16
0.1
10
0.1
0.5
1:1
±400
±1000
±100
±0.05
±2
±25
±200
11
±10
5.5
7
ppm of
FSR⁽⁵⁾, rms
∗
∗
∗
Bits
∗
Bits
∗∗
pA
∗
∗
% of FSR
∗
∗
∗
ppm of FSR
∗
ppm of FSR
∗∗
mV
∗
∗ ppm of FSR/V
∗
pC
∗
%
PERFORMANCE OVER TEMPERATURE
Offset Drift
Offset Drift Stability
DC Bias Voltage Drift⁽⁹⁾
Input Bias Current Drift
Range Drift⁽¹⁰⁾
T_A = +25°C to +45°C
±0.5
±0.2
3
0.01
25
±3⁽⁸⁾
±1⁽⁸⁾
1⁽⁸⁾
∗∗
ppm of
FSR/°C
∗
∗
ppm of FSR/
minute
∗
µV/°C
∗∗
pA/°C
∗
ppm/°C
REFERENCE
Voltage
Input Current⁽¹¹⁾
Average Value
4.000
4.096
4.200
∗∗∗
V
150
190
µA
(1) _{∗ indicates that specification is the same as Low-Power Mode.}
(2) _{Exceeding maximum input current specification may damage device.}
(3) _{Input is less than 1% of full scale.}
(4) _{CSENSOR is the capacitance seen at the DDC118 inputs from wiring, photodiode, etc.}
(5) _{FSR is Full-Scale Range.}
(6) _{A best-fit line is used in measuring nonlinearity.}
(7) _{Matching between side A and side B of the same input.}
(8) _{Ensured by design, not production tested.}
(9) _{Voltage produced by the DDC118 at its input which is applied to the sensor.}
(10)Range _{drift does not include external reference drift.}
(11)Input _{reference current decreases with increasing TINT (see the Voltage Reference section, page 11).}
(12)Data _{format is Straight Binary with a small offset. The number of bits in the output word is controlled by the FORMAT pin (see text).}
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