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ADS1216
S1
216
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
8-Channel, 24-Bit
ANALOG-TO-DIGITAL CONVERTER
FEATURES
•
•
•
•
•
•
•
•
•
•
•
•
24 BITS, NO MISSING CODES
0.0015% INL
22 BITS EFFECTIVE RESOLUTION
(PGA = 1), 19 BITS (PGA = 128)
PGA FROM 1 TO 128
SINGLE-CYCLE SETTLING MODE
PROGRAMMABLE DATA OUTPUT RATES:
up to 1kHz
ON-CHIP 1.25V/2.5V REFERENCE
EXTERNAL DIFFERENTIAL REFERENCE:
0.1V to 2.5V
ON-CHIP CALIBRATION
SPI™-COMPATIBLE
2.7V TO 5.25V
< 1mW POWER CONSUMPTION
APPLICATIONS
•
•
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INDUSTRIAL PROCESS CONTROL
LIQUID/GAS CHROMATOGRAPHY
BLOOD ANALYSIS
SMART TRANSMITTERS
PORTABLE INSTRUMENTATION
WEIGHT SCALES
PRESSURE TRANSDUCERS
DESCRIPTION
The ADS1216 is a precision, wide dynamic range,
delta-sigma, Analog-to-Digital (A/D) converter with
24-bit resolution operating from 2.7V to 5.25V
supplies. The delta-sigma A/D converter provides up
to 24 bits of no-missing-code performance and an
effective resolution of 22 bits.
The eight input channels are multiplexed. Internal
buffering can be selected to provide a very high input
impedance for direct connection to transducers or
low-level voltage signals. Burnout current sources
are provided that allow for the detection of an open
or shorted sensor. An 8-bit Digital-to-Analog
Converter (DAC) provides an offset correction with a
range of 50% of the FSR (Full-Scale Range).
The PGA (Programmable Gain Amplifier) provides
selectable gains of 1 to 128 with an effective
resolution of 19 bits at a gain of 128. The A/D
conversion is accomplished with a second-order
delta-sigma modulator and programmable sinc filter.
The reference input is differential and can be used
for ratiometric cancellation. The onboard current
DACs operate independently with the maximum
current set by an external resistor.
The serial interface is SPI-compatible. Eight bits of
digital I/O are also provided that can be used for
input or output. The ADS1216 is designed for
high-resolution measurement applications in smart
transmitters, industrial process control, weight
scales,
chromatography,
and
portable
instrumentation.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SPI is a trademark of Motorola.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2000–2006, Texas Instruments Incorporated
ADS1216
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be
more susceptible to damage because very small parametric changes could cause the device not to meet its published
specifications.
ORDERING INFORMATION
For the most current package and ordering information see the Package Option Addendum at the end of this
document, or see the TI web site at www.ti.com.
ABSOLUTE MAXIMUM RATINGS (1)
AVDD to AGND
DVDD to DGND
Input Current
Input Current
AIN
UNIT
V
–0.3 to +6
V
100, Momentary
mA
10, Continuous
mA
GND – 0.5 to AVDD + 0.5
V
AVDD to DVDD
–6 to +6
V
–0.3 to +0.3
V
Digital Input Voltage to GND
–0.3 to DVDD + 0.3
V
Digital Output Voltage to GND
–0.3 to DVDD + 0.3
V
+150
°C
Operating Temperature Range
–40 to +85
°C
Storage Temperature Range
–60 to +100
°C
AGND to DGND
Maximum Junction Temperature
(1)
2
ADS1216
–0.3 to +6
Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may
degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond
those specified is not implied.
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
ELECTRICAL CHARACTERISTICS: AVDD = +5V
All specifications at TMIN to TMAX, AVDD = +5V, DVDD = +2.7V to +5.25V, fMOD = 19.2kHz, PGA = 1, Buffer ON, RDAC = 150kΩ,
fDATA = 10Hz, and VREF = +2.5V, unless otherwise specified.
ADS1216
PARAMETER
CONDITIONS
MIN
TYP
Buffer OFF
AGND – 0.1
Buffer ON
AGND + 0.05
MAX
UNIT
AVDD + 0.1
V
AVDD – 1.5
V
±VREF/PGA
V
ANALOG INPUT (AIN0 – AIN7, AINCOM)
Analog input range
Full-scale input voltage range
(In+) – (In–); see Functional Block
Diagram
Differential input impedance
Buffer OFF
5/PGA
MΩ
Input current
Buffer ON
0.5
nA
Fast-settling filter
–3dB
0.469 × fDATA
Hz
Sinc2 filter
–3dB
0.318 × fDATA
Hz
Sinc3 filter
–3dB
0.262 × fDATA
Bandwidth
Programmable gain amplifier
User-selectable gain ranges
1
Input capacitance
Input leakage current
Modulator OFF, TA = +25°C
Burnout current sources
Hz
128
9
pF
5
pA
2
µA
OFFSET DAC
±VREF /(2 × PGA)
Offset DAC range
Offset DAC monotonicity
V
8
Offset DAC gain error
Offset DAC gain error drift
Bits
±10
%
1
ppm/°C
SYSTEM PERFORMANCE
Resolution
24
No missing codes
Integral nonlinearity
Bits
Sinc3 filter
24
Bits
End-point fit
±0.0015
% of FS
Offset error (1)
7.5
ppm of FS
Offset drift (1)
0.02
ppm of FS/°C
Gain error (1)
0.005
%
0.5
ppm/°C
Gain error drift (1)
Common-mode rejection
Normal-mode rejection
At DC
100
130
dB
fCM = 50Hz, fDATA = 50Hz
120
dB
fCM = 60Hz, fDATA = 60Hz
120
dB
fSIG = 50Hz, fDATA = 50Hz
100
dB
fSIG = 60Hz, fDATA = 60Hz
100
dB
Output noise
Power-supply rejection
dB
fCM = 60Hz, fDATA = 10Hz
See Typical Characteristics
At DC, dB = –20 log(∆VOUT/∆VDD) (2)
80
REF IN+, REF IN–
AGND
VREF ≡ (REF IN+) – (REF IN–)
0.1
95
dB
VOLTAGE REFERENCE INPUT
Reference input range
VREF
AVDD
2.5
2.6
V
V
Common-mode rejection
at DC
120
dB
Common-mode rejection
fVREFCM = 60Hz, fDATA = 60Hz
120
dB
VREF = 2.5V
1.3
µA
Bias current (3)
(1)
(2)
(3)
Calibration can minimize these errors.
∆ VOUT is change in digital result.
12pF switched capacitor at fSAMP clock frequency.
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
ELECTRICAL CHARACTERISTICS: AVDD = +5V (continued)
All specifications at TMIN to TMAX, AVDD = +5V, DVDD = +2.7V to +5.25V, fMOD = 19.2kHz, PGA = 1, Buffer ON, RDAC = 150kΩ,
fDATA = 10Hz, and VREF = +2.5V, unless otherwise specified.
ADS1216
PARAMETER
CONDITIONS
MIN
REF HI = 1
2.4
TYP
MAX
UNIT
2.5
2.6
V
ON-CHIP VOLTAGE REFERENCE
Output voltage
REF HI = 0
Short-circuit current source
Short-circuit current sink
Short-circuit duration
Sink or source
Output impedance
V
8
mA
50
µA
Indefinite
Drift
Noise
1.25
15
ppm/°C
VRCAP = 0.1µF, BW = 0.1Hz to 100Hz
10
µVPP
Sourcing 100µA
3
Ω
50
µs
RDAC = 150kΩ, range = 1
0.5
mA
RDAC = 150kΩ, range = 2
1
mA
RDAC = 150kΩ, range = 3
2
mA
mA
Startup time
IDAC
Full-scale output current
RDAC = 15kΩ, range = 3
20
Maximum short-circuit current duration
RDAC = 10kΩ
Indefinite
Monotonicity
RDAC = 150kΩ
RDAC = 0kΩ
10
8
Compliance voltage
Bits
0
Output impedance
Minute
AVDD – 1
V
See Typical Characteristics
Power-supply rejection ratio
VOUT = AVDD/2
400
Absolute error
Individual IDAC
5
ppm/V
%
Absolute drift
Individual IDAC
75
ppm/°C
Mismatch error
Between IDACs, same range and code
0.25
%
Mismatch drift
Between IDACs, same range and code
15
ppm/°C
POWER-SUPPLY REQUIREMENTS
Power-supply voltage
Analog current (IADC + IVREF + IDAC)
ADC current (IADC)
AVDD
4.75
1
Digital current
Power dissipation
V
nA
PGA = 1, buffer OFF
140
225
µA
PGA = 128, buffer OFF
430
650
µA
PGA = 1, buffer ON
180
275
µA
PGA = 128, buffer ON
800
1250
µA
250
375
µA
Excludes load current
480
675
µA
Normal mode, DVDD = 5V
180
275
µA
SLEEP mode, DVDD = 5V
150
µA
Read data continuous mode, DVDD = 5V
230
µA
PDWN
1
nA
PGA = 1, buffer OFF, REFEN = 0,
IDACS OFF, DVDD = 5V
1.6
VREF current (IVREF)
IDAC current (IDAC)
5.25
PDWN = 0 or SLEEP
2.5
mW
TEMPERATURE RANGE
4
Operating
–40
+85
°C
Storage
–60
+100
°C
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
ELECTRICAL CHARACTERISTICS: AVDD = +3V
All specifications at TMIN to TMAX, AVDD = +3V, DVDD = +2.7V to +5.25V, fMOD = 19.2kHz, PGA = 1, Buffer ON, RDAC = 75kΩ,
fDATA = 10Hz, and VREF = +1.25V, unless otherwise specified.
ADS1216
PARAMETER
CONDITIONS
MIN
TYP
Buffer OFF
AGND – 0.1
Buffer ON
AGND + 0.05
MAX
UNIT
AVDD + 0.1
V
AVDD – 1.5
V
±VREF/PGA
V
ANALOG INPUT (AIN0 – AIN7, AINCOM)
Analog input range
Full-scale input voltage range
(In+) – (In–); see Functional Block
Diagram
Input impedance
Buffer OFF
5/PGA
MΩ
Input current
Buffer ON
0.5
nA
Fast-settling filter
–3dB
0.469 × fDATA
Hz
Sinc2 filter
–3dB
0.318 × fDATA
Hz
Sinc3 filter
–3dB
0.262 × fDATA
Bandwidth
Programmable gain amplifier
User-selectable gain ranges
1
Input capacitance
Input leakage current
Modulator OFF, TA = +25°C
Burnout current sources
Hz
128
9
pF
5
pA
2
µA
OFFSET DAC
±VREF /(2 × PGA)
Offset DAC range
Offset DAC monotonicity
V
8
Offset DAC gain error
Offset DAC gain error drift
Bits
±10
%
2
ppm/°C
SYSTEM PERFORMANCE
Resolution
24
No missing codes
Integral nonlinearity
Bits
Sinc3 filter
24
Bits
End-point fit
±0.0015
% of FS
Offset error (1)
15
ppm of FS
Offset drift (1)
0.04
ppm of FS/°C
Gain error (1)
0.010
%
1.0
ppm/°C
Gain error drift (1)
Common-mode rejection
Normal-mode rejection
At DC
100
130
dB
fCM = 50Hz, fDATA = 50Hz
120
dB
fCM = 60Hz, fDATA = 60Hz
120
dB
fSIG = 50Hz, fDATA = 50Hz
100
dB
fSIG = 60Hz, fDATA = 60Hz
100
dB
Output noise
Power-supply rejection
dB
fCM = 60Hz, fDATA = 10Hz
See Typical Characteristics
At DC, dB = –20 log(∆VOUT/∆VDD) (2)
75
90
dB
VOLTAGE REFERENCE INPUT
Reference input range
VREF
REF IN+, REF IN–
0
VREF ≡ (REF IN+) – (REF IN–)
0.1
Common-mode rejection
at DC
Common-mode rejection
Bias current (3)
(1)
(2)
(3)
AVDD
1.25
1.3
V
V
120
dB
fVREFCM = 60Hz, fDATA = 60Hz
120
dB
VREF = 1.25V
0.65
µA
Calibration can minimize these errors.
∆ VOUT is change in digital result.
12pF switched capacitor at fSAMP clock frequency.
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
ELECTRICAL CHARACTERISTICS: AVDD = +3V (continued)
All specifications at TMIN to TMAX, AVDD = +3V, DVDD = +2.7V to +5.25V, fMOD = 19.2kHz, PGA = 1, Buffer ON, RDAC = 75kΩ,
fDATA = 10Hz, and VREF = +1.25V, unless otherwise specified.
ADS1216
PARAMETER
CONDITIONS
MIN
TYP
MAX
REF HI = 0
1.2
1.25
1.3
UNIT
ON-CHIP VOLTAGE REFERENCE
Output voltage
Short-circuit current source
Short-circuit current sink
Short-circuit duration
Sink or source
Output impedance
mA
50
µA
Indefinite
Drift
Noise
V
3
15
ppm/°C
VRCAP = 0.1µF, BW = 0.1Hz to 100Hz
10
µVPP
Sourcing 100µA
3
Ω
50
µs
RDAC = 75kΩ, range = 1
0.5
mA
RDAC = 75kΩ, range = 2
1
mA
RDAC = 75kΩ, range = 3
2
mA
RDAC = 15kΩ, range = 3
20
mA
RDAC = 10kΩ
Indefinite
Startup time
IDAC
Full-scale output current
Maximum short-circuit current duration
RDAC = 0kΩ
Monotonicity
10
RDAC = 75kΩ
8
Compliance voltage
Bits
0
Output impedance
Minute
AVDD – 1
V
See Typical Characteristics
Power-supply rejection ratio
VOUT = AVDD/2
600
Absolute error
Individual IDAC
5
ppm/V
%
Absolute drift
Individual IDAC
75
ppm/°C
Mismatch error
Between IDACs, same range and code
0.25
%
Mismatch drift
Between IDACs, same range and code
15
ppm/°C
POWER-SUPPLY REQUIREMENTS
Power-supply voltage
Analog current (IADC + IVREF + IDAC)
ADC current (IADC)
AVDD
2.7
1
Digital current
Power dissipation
V
nA
PGA = 1, buffer OFF
120
200
µA
PGA = 128, buffer OFF
370
600
µA
PGA = 1, buffer ON
170
250
µA
PGA = 128, buffer ON
750
1200
µA
250
375
µA
Excludes load current
480
675
µA
Normal mode, DVDD = 3V
90
200
µA
VREF current (IVREF)
IDAC current (IDAC)
3.3
PDWN = 0 or SLEEP
SLEEP mode, DVDD = 3V
75
µA
Read data continuous mode, DVDD = 3V
113
µA
PDWN = 0
1
nA
PGA = 1, buffer OFF, REFEN = 0,
IDACS OFF, DVDD = 3V
0.6
1.2
mW
TEMPERATURE RANGE
6
Operating
–40
+85
°C
Storage
–60
+100
°C
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
DIGITAL CHARACTERISTICS: TMIN to TMAX, DVDD +2.7V to +5.25V
ADS1216
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
Digital input/output
Logic family
CMOS
Logic level: VIH
0.8 × DVDD
DVDD
V
Logic level: VIL
DGND
0.2 × DVDD
V
Logic level: VOH
IOH = 1mA
DVDD – 0.4
Logic level: VOL
IOL = 1mA
DGND
Input leakage: IIH
VI = DVDD
Input leakage: IIL
VI = 0
V
10
µA
1
5
MHz
200
1000
ns
µA
–10
Master clock rate: fOSC
Master clock period: tOSC
V
DGND + 0.4
1/fOSC
FUNCTIONAL BLOCK DIAGRAM
AGND
RDAC
AVDD
VREFOUT
VREF+
VRCAP
VREF-
XIN
XOUT
8-Bit
IDAC
IDAC2
8-Bit
IDAC
IDAC1
AVDD
2m A
Clock Generator
1.25V or
2.5V
Reference
Offset
DAC
AIN0
A = 1:128
AIN1
Registers
IN+
AIN2
AIN3
MUX
AIN4
IN-
BUF
+
2nd-Order
Modulator
PGA
Programmable
Digital
Filter
Controller
RAM
AIN5
AIN6
AIN7
AINCOM
POL
2m A
Serial Interface
Digital I/O
Interface
AGND
DVDD
DGND
SCLK
DIN
DOUT
CS
BUFEN
D0
... D7
PDWN
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DSYNC
RESET
DRDY
7
ADS1216
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
TIMING CHARACTERISTICS
CS
t3
t1
t2
t10
SCLK
(POL = 0)
SCLK
(POL = 1)
t4
DIN
MSB
t2
t6
t5
t11
LSB
(Command or Command and Data)
t7
DOUT
t8
MSB
t9
(1)
LSB
(1)
NOTE: (1) Bit Order = 0.
SPEC
t1
DESCRIPTION
MIN
SCLK period
t2
SCLK pulse width, HIGH and LOW
t3
t4
t5
MAX
UNITS
3
DRDY periods
4
tOSC periods
200
ns
CS LOW to first SCLK edge; setup time
0
ns
DIN valid to SCLK edge; setup time
50
ns
Valid DIN to SCLK edge; hold time
50
ns
RDATA, RDATAC, RREG, WREG, RRAM, WRAM
50
tOSC periods
CSREG, CSRAMX, CSRAM
200
tOSC periods
CSARAM, CSARAMX
1100
tOSC periods
Delay between last SCLK edge for DIN and first SCLK edge for DOUT:
t6
t7
SCLK edge to valid new DOUT
t8
SCLK edge to DOUT, hold time
0
50
ns
t9
Last SCLK edge to DOUT tri-state
NOTE: DOUT goes tri-state immediately when CS goes HIGH.
6
t10
CS LOW time after final SCLK edge
16
tOSC periods
4
tOSC periods
CREG, CRAM
220
tOSC periods
CREGA
1600
tOSC periods
SELFGCAL, SELFOCAL, SYSOCAL, SYSGCAL
7
DRDY periods
SELFCAL
14
DRDY periods
RESET (Command, SCLK or Pin), DSYNC
16
tOSC periods
ns
10
tOSC periods
Final SCLK edge of one op code until first edge SCLK of next command:
RREG, WREG, RRAM, WRAM, CSRAMX, CSARAMX, CSRAM,
CSARAM, CSREG, SLEEP, RDATA, RDATAC, STOPC
t11
8
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
ADS1216
Resets On
Falling Edge
SCLK Reset Waveform
t13
t13
SCLK
t12
t14
t15
t16
t17A
RESET, DSYNC, PDWN
DRDY
t17B
SPEC
DESCRIPTION
t12
MIN
MAX
UNITS
300
500
tOSC periods
t13
5
t14
550
750
tOSC periods
t15
1050
1250
tOSC periods
4
tOSC periods
DOR data not valid during this update period
4
tOSC periods
DOR data not valid during this update period
12
tOSC periods
SCLK
CS
DRDY
DVDD
DGND
DSYNC
POL
PDWN
XOUT
XIN
DEVICE INFORMATION
DIN
36
35
34
33
32
31
30
29
28
27
26
25
D0 37
24 RESET
D1 38
23 BUFEN
D2 39
22 DGND
D3 40
21 DGND
D4 41
20 DGND
D5 42
19 DGND
ADS1216
D6 43
18 DGND
D7 44
17 RDAC
2
3
4
5
6
7
8
9
10
11
12
AGND
1
AINCOM
13 AVDD
AIN7
VREF- 48
AIN6
14 VRCAP
AIN5
VREF+ 47
AIN4
15 IDAC1
AIN3
VREFOUT 46
AIN2
16 IDAC2
AIN1
AGND 45
AIN0
t17B
AGND
t17A
DOUT
Pulse width
AVDD
t16
tOSC periods
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
DEVICE INFORMATION (continued)
TERMINAL FUNCTIONS
PIN NUMBER
10
NAME
DESCRIPTION
1, 13
AVDD
Analog power supply
2, 12, 45
AGND
Analog ground
3–10
AIN0–7
Analog input 0–7
11
AINCOM
Analog input common
14
VRCAP
VREF bypass capcitor
15
IDAC1
Current DAC1 output
16
IDAC2
Current DAC2 output
17
RDAC
Current DAC resistor
18–22, 30
DGND
Digital ground
23
BUFEN
Buffer enable
24
RESET
Active LOW; resets the entire chip.
25
XIN
26
XOUT
27
PDWN
28
POL
29
DSYNC
Clock input
Clock output, used with crystal or resonator.
Active LOW; power down. The power-down function shuts down the analog and digital circuits.
Serial clock polarity
Active LOW; synchronization control
31
DVDD
Digital power supply
32
DRDY
Active LOW; data ready
33
CS
Active LOW; chip select
34
SCLK
Serial clock, Schmitt trigger
35
DIN
36
DOUT
Serial data input, Schmitt trigger
37–44
D0–D7
46
VREFOUT
47
VREF+
Positive differential reference input
48
VREF–
Negative differential reference input
Serial data output
Digital I/O 0–7
Voltage reference output
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
TYPICAL CHARACTERISTICS
At AVDD = +5V, DVDD = +5V, fOSC = 2.4576MHz, PGA = 1, RDAC = 150kΩ, fDATA = 10Hz, and VREF = +2.5V, unless otherwise specified.
EFFECTIVE NUMBER OF BITS
vs DECIMATION RATIO
22
22
PGA8
21
21
20
20
19
19
18
PGA16
17
PGA32
PGA64
ENOB (rms)
ENOB (rms)
PGA4
PGA2
PGA1
EFFECTIVE NUMBER OF BITS
vs DECIMATION RATIO
PGA128
16
18
17
14
PGA16
14
3
Sinc Filter
13
13
3
Sinc Filter, Buffer ON
12
12
0
500
1000
1500
0
2000
500
Decimation Ratio = fMOD/fDATA
22
1500
Figure 1.
Figure 2.
EFFECTIVE NUMBER OF BITS
vs DECIMATION RATIO
EFFECTIVE NUMBER OF BITS
vs DECIMATION RATIO
PGA2
PGA1
20
20
19
19
18
PGA32
PGA16
PGA4
PGA2
21
17
2000
22
PGA8
PGA4
21
16
1000
Decimation Ratio = fMOD/fDATA
ENOB (rms)
ENOB (rms)
PGA128
PGA64
PGA32
16
15
15
PGA128
PGA64
PGA8
PGA1
18
17
16
PGA16
15
15
PGA32
PGA128
PGA64
14
14
13
13
3
Sinc Filter, VREF = 1.25V, BUFFER OFF
12
0
500
1000
1500
3
Sinc Filter, VREF = 1.25, BUFFER ON
12
0
2000
500
Decimation Ratio = fMOD/fDATA
1000
1500
2000
Decimation Ratio
Figure 3.
Figure 4.
EFFECTIVE NUMBER OF BITS
vs DECIMATION RATIO
FAST-SETTLING FILTER
EFFECTIVE NUMBER OF BITS vs DECIMATION RATIO
22
22
PGA2
21
PGA4
PGA8
21
PGA1
20
20
19
19
18
17
PGA32
PGA16
PGA64
PGA128
16
ENOB (rms)
ENOB (rms)
PGA8
PGA4
PGA2
PGA1
18
17
16
15
15
14
14
2
Sinc Filter
13
13
Fast-Settling Filter
12
12
0
500
1000
1500
2000
0
Decimation Ratio = fMOD/fDATA
500
1000
1500
2000
Decimation Ratio = fMOD/fDATA
Figure 5.
Figure 6.
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TYPICAL CHARACTERISTICS (continued)
At AVDD = +5V, DVDD = +5V, fOSC = 2.4576MHz, PGA = 1, RDAC = 150kΩ, fDATA = 10Hz, and VREF = +2.5V, unless otherwise specified.
NOISE vs INPUT SIGNAL
CMRR vs FREQUENCY
0.8
0.6
0.5
CMRR (dB)
Noise (rms, ppm of FS)
0.7
0.4
0.3
0.2
0.1
0
-2.5
-1.5
0.5
-0.5
1.5
130
120
110
100
90
80
70
60
50
40
30
20
10
0
2.5
1
10
VIN (V)
100
Figure 7.
10k
100k
Figure 8.
PSRR vs FREQUENCY
OFFSET vs TEMPERATURE
50
120
110
PGA16
PGA1
100
0
Offset (ppm of FS)
90
80
PSRR (dB)
1k
Frequency of CM Signal (Hz)
70
60
50
40
30
-50
PGA64
-100
PGA128
-150
20
10
0
-200
1
10
100
1k
10k
100k
-50
-30
Figure 9.
10
30
50
70
90
Figure 10.
GAIN vs TEMPERATURE
INTEGRAL NONLINEARITY vs INPUT SIGNAL
10
1.00010
8
1.00006
-40°C
6
INL (ppm of FS)
Gain (Normalized)
-10
Temperature (°C)
Frequency of Power Supply (Hz)
1.00002
0.99998
0.99994
4
2
+85°C
0
-2
-4
+25°C
-6
0.99990
-8
0.99986
-50
-30
-10
10
30
50
70
90
-10
-2.5 -2.0 -1.5 -1.0 -0.5
Figure 11.
12
0
0.5
VIN (V)
Temperature (°C)
Figure 12.
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1.5
2.0
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TYPICAL CHARACTERISTICS (continued)
At AVDD = +5V, DVDD = +5V, fOSC = 2.4576MHz, PGA = 1, RDAC = 150kΩ, fDATA = 10Hz, and VREF = +2.5V, unless otherwise specified.
CURRENT vs TEMPERATURE
250
ADC CURRENT vs PGA
900
IDIGITAL
AVDD = 5V, Buffer = ON
800
Buffer = OFF
700
600
150
IADC (mA)
Current (mA)
200
IANALOG
100
500
AVDD = 3V, Buffer = ON
400
Buffer = OFF
300
200
50
100
0
0
-50
-30
10
-10
30
50
70
90
0
1
4
8
16
PGA Setting
Figure 13.
Figure 14.
DIGITAL CURRENT
32
64
128
HISTOGRAM OF OUTPUT DATA
400
4500
Normal
4.91MHz
300
Normal
2.45MHz
250
4000
Number of Occurrences
350
Current (mA)
2
Temperature (°C)
SLEEP
4.91MHz
200
150
100
50
SLEEP
2.45MHz
Power-Down
3500
3000
2500
2000
1500
1000
500
0
0
3.0
4.0
5.0
-2.0
-1.5
-1.0 -0.5
VDD (V)
0
0.5
1.0
1.5
2.0
ppm of FS
Figure 15.
Figure 16.
VREFOUT vs LOAD CURRENT
OFFSET DAC – OFFSET vs TEMPERATURE
200
2.55
170
Offset (ppm of FSR)
VREFOUT (V)
140
2.50
110
80
50
20
-10
-40
-70
2.45
-0.5
-100
0
0.5
1.0
1.5
2.0
2.5
-50
-30
-10
10
30
50
70
90
Temperature (°C)
VREFOUT Current Load (mA)
Figure 17.
Figure 18.
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TYPICAL CHARACTERISTICS (continued)
At AVDD = +5V, DVDD = +5V, fOSC = 2.4576MHz, PGA = 1, RDAC = 150kΩ, fDATA = 10Hz, and VREF = +2.5V, unless otherwise specified.
OFFSET DAC – GAIN vs TEMPERATURE
IDAC ROUT vs VOUT
1.00020
1.000
1.00016
+85°C
1.000
1.00008
IOUT (Normalized)
Normalized Gain
1.00012
1.00004
1.00000
0.99996
0.99992
0.99988
+25°C
0.999
0.999
0.99984
-40°C
0.99980
0.99976
0.998
-50
-30
10
-10
30
50
70
90
0
1
2
3
Temperature (°C)
VDD - VOUT (V)
Figure 19.
Figure 20.
IDAC NORMALIZED vs TEMPERATURE
4
5
IDAC MATCHING vs TEMPERATURE
1.010
3000
2000
1000
IDAC Match (ppm)
IOUT (Normalized)
1.005
1.000
0.995
0
-1000
-2000
-3000
-4000
0.990
-5000
0.985
-6000
-50
-30
10
-10
30
50
70
90
-50
-30
50
70
Figure 21.
Figure 22.
IDAC DIFFERENTIAL NONLINEARITY
(Range = 1, RDAC = 150kΩ, VREF = 2.5V)
IDAC INTEGRAL NONLINEARITY
(Range = 1, RDAC = 150kΩ, VREF = 2.5V)
0.5
0.5
0.4
0.4
0.3
0.3
0.2
0.2
0.1
0.1
INL (LSB)
DNL (LSB)
30
90
Temperature (°C)
0
-0.1
0
-0.1
-0.2
-0.2
-0.3
-0.3
-0.4
-0.4
-0.5
-0.5
0
14
10
-10
Temperature (°C)
32
64
96
128
160
192
224
255
0
32
64
96
128
160
IDAC Code
IDAC Code
Figure 23.
Figure 24.
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224
255
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OVERVIEW
INPUT MULTIPLEXER
The input multiplexer provides for any combination of
differential inputs to be selected on any of the input
channels, as shown in Figure 25. If channel 1 is
selected as the positive differential input channel,
any other channel can be selected as the negative
differential input channel. With this method, it is
possible to have up to eight fully-differential input
channels.
In addition, current sources are supplied that will
source or sink current to detect open or short circuits
on the pins.
AIN0
AIN1
AVDD
Burnout Current
Source On
AIN2
of the diode is connected to the negative input of the
A/D converter. The output of IDAC1 is connected to
the anode to bias the diode and the cathode of the
diode is also connected to ground to complete the
circuit.
In this mode, the output of IDAC1 is also connected
to the output pin, so some current may flow into an
external load from IDAC1, rather than the diode. See
Application Report Measuring Temperature with the
ADS1216, ADS1217, or ADS1216 (SBAA073),
available for download at www.ti.com, for more
information.
BURNOUT CURRENT SOURCES
When the Burnout bit is set in the ACR Configuration
Register (see the Register Map section), two current
sources are enabled. The current source on the
positive input channel sources approximately 2µA of
current. The current source on the negative input
channel sinks approximately 2µA. This sinking allows
for the detection of an open circuit (full-scale
reading) or short circuit (0V differential reading) on
the selected input differential pair.
INPUT BUFFER
AIN3
AIN4
AIN5
Burnout Current
Source On
AIN6
The input impedance of the ADS1216 without the
buffer is 5MΩ/PGA. With the buffer enabled, the
input voltage range is reduced and the analog
power-supply current is higher. The buffer is
controlled by ANDing the state of the buffer pin with
the state of the BUFFER bit in the ACR Register
(see the Register Map section). See Application
Report Input Currents for High-Resolution ADCs
(SBAA080), available for download at www.ti.com,
for more information.
AGND
IDAC1
AIN7
AINCOM
Figure 25. Input Multiplexer Configuration
TEMPERATURE SENSOR
An on-chip diode provides temperature sensing
capability. When the configuration register for the
input MUX is set to all 1s, the diode is connected to
the input of the A/D converter. All other channels are
open. The anode of the diode is connected to the
positive input of the A/D converter, and the cathode
IDAC1 AND IDAC2
The ADS1216 has two 8-bit current output DACs that
can be controlled independently. The output current
is set with RDAC, the range select bits in the ACR
register, and the 8-bit digital value in the IDAC
register. The output current equals VREF/(8 ×
RDAC)(2RANGE – 1)(DAC CODE). With VREFOUT = 2.5V
and RDAC = 150kΩ, the full-scale output can be
selected to be 0.5, 1, or 2mA. The compliance
voltage range is 0 to within 1V of AVDD. When the
internal voltage reference of the ADS1216 is used, it
is the reference for the IDAC. An external reference
may be used for the IDACs by disabling the internal
reference and tying the external reference input to
the VREFOUT pin.
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PROGRAMMABLE GAIN AMPLIFIER (PGA)
ON-CHIP VOLTAGE REFERENCE
The PGA can be set to gains of 1, 2, 4, 8, 16, 32, 64,
or 128. Using the PGA can improve the effective
resolution of the A/D converter. For instance, with a
PGA of 1 on a 5V full-scale range, the A/D converter
can resolve to 1µV. With a PGA of 128 on a 40mV
full-scale range, the A/D converter can resolve to
75nV.
A selectable voltage reference (1.25V or 2.5V) is
available for supplying the voltage reference input.
To use, connect VREF– to AGND and VREF+ to
VREFOUT. The enabling and voltage selection are
controlled through bits REF EN and REF HI in the
Setup Register (see the Register Map section). The
2.5V reference requires AVDD = +5V. When using the
on-chip voltage reference, the VREFOUT pin should be
bypassed with a 0.1µF capacitor to AGND.
PGA OFFSET DAC
The input to the PGA can be shifted by half the
full-scale input range of the PGA by using the ODAC
(Offset DAC) Register; see the Register Map section.
The ODAC register is an 8-bit value; the MSB is the
sign and the seven LSBs provide the magnitude of
the offset. Using the ODAC does not reduce the
performance of the A/D converter. See Application
Report The Offset DAC (SBAA077), available for
download at www.ti.com, for more information.
VRCAP PIN
This pin provides a bypass cap for noise filtering on
internal VREF circuitry only. This pin is a sensitive pin;
therefore place the capacitor as close as possible
and avoid any resistive loading. The recommended
capacitor is a 1000pF ceramic cap. If an external
VREF is used, this pin can be left unconnected.
CLOCK GENERATOR
MODULATOR
The modulator is a single-loop, second-order system.
The modulator runs at a clock speed (fMOD) that is
derived from the external clock (fOSC), as shown in
Table 1. The frequency division is determined by the
SPEED bit in the Setup Register (see the Register
Map section).
The clock source for the ADS1216 can be provided
from a crystal, oscillator, or external clock. When the
clock source is a crystal, external capacitors must be
provided to ensure startup and a stable clock
frequency; this configuration is shown in Figure 26
and Table 2.
C1
Table 1. Modulator Speed
XIN
Crystal
SPEED BIT
fMOD
0
fOSC/128
1
fOSC/256
C2
Figure 26. Crystal Connection
VOLTAGE REFERENCE INPUT
The ADS1216 uses a differential voltage reference
input. The input signal is measured against the
differential voltage VREF ≡ (VREF+) – (VREF–). For AVDD
= +5V, VREF is typically +2.5V. For AVDD = +3V, VREF
is typically +1.25V. As a result of the sampling nature
of the modulator, the reference input current
increases with higher modulator clock frequency
(fMOD) and higher PGA settings.
16
XOUT
Table 2. Typical Clock Sources
CLOCK
SOURCE
FREQUENCY
C1
C2
PART NUMBER
Crystal
2.4576
0–20pF
0–20pF
ECS, ECSD 2.45 – 32
Crystal
4.9152
0–20pF
0–20pF
ECS, ECSL 4.91
Crystal
4.9152
0–20pF
0–20pF
ECS, ECSD 4.91
Crystal
4.9152
0–20pF
0–20pF
CTS, MP 042 4M9182
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CALIBRATION
At the completion of calibration, the DRDY signal
goes low, which indicates the calibration is finished
and valid data is available. See Application Report
Calibration Routine and Register Value Generation
for the ADS121x Series (SBAA099), available for
download at www.ti.com, for more information.
The offset and gain errors in the ADS1216, or the
complete system, can be reduced with calibration.
Internal calibration of the ADS1216 is called
self-calibration. Self-calibration is handled with three
commands. One command does both offset and gain
calibration. There is also a gain calibration command
and an offset calibration command. Each calibration
process takes seven tDATA periods to complete. It
takes 14 tDATA periods to complete both an offset and
gain calibration. Self-gain calibration is optimized for
PGA gains less than 8. When using higher gains,
system gain calibration is recommended.
DIGITAL FILTER
The Digital Filter can use either the Fast-Settling,
Sinc2, or Sinc3 filter, as shown in Figure 27. In
addition, the Auto mode changes the sinc filter after
the input channel or PGA is changed. When
switching to a new channel, it will use the
Fast-Settling filter for the next two conversions, the
first of which should be discarded. It will then use the
Sinc2 followed by the Sinc3 filter. This architecture
combines the low-noise advantage of the Sinc3 filter
with the quick response of the Fast-Settling time
filter. See Figure 28 for the frequency response of
each filter.
For system calibration, the appropriate signal must
be applied to the inputs. The system offset command
requires a zero differential input signal. It then
computes an offset that will nullify offset in the
system. The system gain command requires a
positive full-scale differential input signal. It then
computes a value to nullify gain errors in the system.
Each of these calibrations will take seven tDATA
periods to complete.
When using the Fast-Settling filter, select a
decimation value set by the DEC0 and M/DEC1
registers that is evenly divisible by four for the best
gain accuracy. For example, choose 260 rather than
261.
Calibration must be performed after power on, a
change in decimation ratio, or a change of the PGA.
For operation with a reference voltage greater than
(AVDD – 1.5V), the buffer must also be turned off
during calibration.
Adjustable Digital Filter
Sinc
Modulator
Output
3
Sinc
2
Data Out
Fast-Settling
AUTO MODE FILTER SELECTION
FILTER SETTLING TIME
FILTER
3
Sinc
2
Sinc
Fast
SETTLING TIME
(Conversion Cycles)
(1)
3
(1)
2
(1)
1
CONVERSION CYCLE
1
2
3
Discard
Fast
Sinc
4
2
Sinc
3
NOTE: (1) With Synchronized Channel Changes.
Figure 27. Filter Step Responses
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3
(1)
2
(1)
SINC FILTER RESPONSE
(-3dB = 0.318 ´ fDATA = 19.11Hz)
0
0
-20
-20
-40
-40
Gain (dB)
Gain (dB)
SINC FILTER RESPONSE
(-3dB = 0.262 ´ fDATA = 15.76Hz)
-60
-60
-80
-80
-100
-100
-120
-120
0
30
60
90
120
150 180
210 240 270 300
0
30
60
90
Frequency (Hz)
120
150 180
210 240 270 300
Frequency (Hz)
FAST SETTLING FILTER RESPONSE
(-3dB = 0.469 ´ fDATA = 28.125Hz)
(1)
0
-20
Gain (dB)
-40
-60
-80
-100
-120
0
30
60
90
120
150 180
210 240 270 300
Frequency (Hz)
NOTE: (1) fDATA = 60Hz.
Figure 28. Filter Frequency Responses
DIGITAL I/O INTERFACE
Chip Select (CS)
The ADS1216 has eight pins dedicated for digital
I/O. The default power-up condition for the digital I/O
pins are as inputs. All of the digital I/O pins are
individually configurable as inputs or outputs. They
are configured through the DIR control register. The
DIR register defines whether the pin is an input or
output, and the DIO register defines the state of the
digital output. When the digital I/O are configured as
inputs, DIO is used to read the state of the pin. If the
digital I/O are not used, either 1) configure as
outputs; or 2) leave as inputs and tie to ground; this
configuration prevents excess power dissipation.
The chip select (CS) input of the ADS1216 must be
externally asserted before a master device can
exchange data with the ADS1216. CS must be low
for the duration of the transaction. CS can be tied
low.
SERIAL PERIPHERAL INTERFACE (SPI)
Serial Clock (SCLK)
SCLK, a Schmitt-Trigger input, clocks data transfer
on the DIN input and DOUT output. When transferring
data to or from the ADS1216, multiple bits of data
may be transferred back-to-back with no delay in
SCLKs or toggling of CS. Make sure to avoid glitches
on SCLK because they can cause extra shifting of
the data.
The SPI allows a controller to communicate
synchronously with the ADS1216. The ADS1216
operates in slave-only mode.
18
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Polarity (POL)
The serial clock polarity is specified by the POL
input. When SCLK is active high, set POL high.
When SCLK is active low, set POL low.
Configuration
Registers
16 bytes
DATA READY
SETUP
MUX
ACR
IDAC1
IDAC2
ODAC
DIO
DIR
DEC0
M/DEC1
OCR0
OCR1
OCR2
FSR0
FSR1
FSR2
The DRDY output is used as a status signal to
indicate when data is ready to be read from the
ADS1216. DRDY goes low when new data is
available. It is reset high when a read operation from
the data register is complete. It also goes high prior
to the updating of the output register to indicate
when not to read from the device to ensure that a
data read is not attempted while the register is being
updated.
RAM
128 Bytes
Bank 0
16 bytes
DSYNC OPERATION
DSYNC is used to provide for synchronization of the
A/D
conversion
with
an
external
event.
Synchronization can be achieved either through the
DSYNC pin or the DSYNC command. When the
DSYNC pin is used, the filter counter is reset on the
falling edge of DSYNC. The modulator is held in
reset until DSYNC is taken high. Synchronization
occurs on the next rising edge of the system clock
after DSYNC is taken high.
Bank 2
16 bytes
MEMORY
Bank 7
16 bytes
Two types of memory are used on the ADS1216:
registers and RAM. 16 registers directly control the
various functions (PGA, DAC value, Decimation
Ratio, etc.) and can be directly read or written to.
Collectively, the registers contain all the information
needed to configure the part, such as data format,
mux settings, calibration settings, decimation ratio,
etc. Additional registers, such as conversion data,
are accessed through dedicated instructions.
Figure 29. Memory Organization
REGISTER BANK
The operation of the device is set up through
individual registers. The set of the 16 registers
required to configure the device is referred to as a
Register Bank, as shown in Figure 29.
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RAM
Reads and Writes to Registers and RAM occur on a
byte basis. However, copies between registers and
RAM occur on a bank basis. The RAM is
independent of the Registers; for example, the RAM
can be used as general-purpose RAM.
The ADS1216 supports any combination of eight
analog inputs. With this flexibility, the device can
easily support eight unique configurations—one per
input channel. In order to facilitate this type of usage,
eight separate register banks are available.
Therefore, each configuration could be written once
and recalled as needed without having to serially
retransmit all the configuration data. Checksum
commands are also included, which can be used to
verify the integrity of RAM.
The RAM provides eight banks, with a bank
consisting of 16 bytes. The total size of the RAM is
128 bytes. Copies between the registers and RAM
are performed on a bank basis. Also, the RAM can
be directly read or written through the serial interface
on power-up. The banks allow separate storage of
settings for each input.
20
The RAM address space is linear; therefore,
accessing RAM is done using an auto-incrementing
pointer. Access to RAM in the entire memory map
can be done consecutively without having to address
each bank individually. For example, if you were
currently accessing bank 0 at offset 0xF (the last
location of bank 0), the next access would be bank 1
and offset 0x0. Any access after bank 7 and offset
0xF will wrap around to bank 0 and Offset 0x0.
Although the Register Bank memory is linear, the
concept of addressing the device can also be
thought of in terms of bank and offset addressing.
Looking at linear and bank addressing syntax, we
have the following comparison: in the linear memory
map, the address 0x14 is equivalent to bank 1 and
offset 0x4. Simply stated, the most significant four
bits represent the bank, and the least significant four
bits represent the offset. The offset is equivalent to
the register address for that bank of memory.
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REGISTER MAP
Table 3. Registers
ADDRESS
REGISTER
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
00h
SETUP
ID
ID
ID
SPEED
REF EN
REF HI
BUF EN
BIT ORDER
01h
MUX
PSEL3
PSEL2
PSEL1
PSEL0
NSEL3
NSEL2
NSEL1
NSEL0
02h
ACR
BOCS
IDAC2R1
IDAC2R0
IDAC1R1
IDAC1R0
PGA2
PGA1
PGA0
03h
IDAC1
IDAC1_7
IDAC1_6
IDAC1_5
IDAC1_4
IDAC1_3
IDAC1_2
IDAC1_1
IDAC1_0
04h
IDAC2
IDAC2_7
IDAC2_6
IDAC2_5
IDAC2_4
IDAC2_3
IDAC2_2
IDAC2_1
IDAC2_0
05h
ODAC
SIGN
OSET_6
OSET_5
OSET_4
OSET_3
OSET_2
OSET_1
OSET_0
06h
DIO
DIO_7
DIO_6
DIO_5
DIO_4
DIO_3
DIO_2
DIO_1
DIO_0
07h
DIR
DIR_7
DIR_6
DIR_5
DIR_4
DIR_3
DIR_2
DIR_1
DIR_0
08h
DEC0
DEC07
DEC06
DEC05
DEC04
DEC03
DEC02
DEC01
DEC00
09h
M/DEC1
DRDY
U/B
SMODE1
SMODE0
Reserved
DEC10
DEC9
DEC8
0Ah
OCR0
OCR07
OCR06
OCR05
OCR04
OCR03
OCR02
OCR01
OCR00
0Bh
OCR1
OCR15
OCR14
OCR13
OCR12
OCR11
OCR10
OCR09
OCR08
0Ch
OCR2
OCR23
OCR22
OCR21
OCR20
OCR19
OCR18
OCR17
OCR16
0Dh
FSR0
FSR07
FSR06
FSR05
FSR04
FSR03
FSR02
FSR01
FSR00
0Eh
FSR1
FSR15
FSR14
FSR13
FSR12
FSR11
FSR10
FSR09
FSR08
0Fh
FSR2
FSR23
FSR22
FSR21
FSR20
FSR19
FSR18
FSR17
FSR16
DETAILED REGISTER DEFINITIONS
SETUP (Address 00h) Setup Register
Reset value = iii01110.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
ID
ID
ID
SPEED
REF EN
REF HI
BUF EN
BIT ORDER
bits 7-5 Factory programmed bits
bit 4
SPEED: modulator clock speed
0 : fMOD = fOSC/128
1 : fMOD = fOSC/256
bit 3
REF EN: Internal voltage reference enable
0 = Internal voltage reference disabled
1 = Internal voltage reference enabled
bit 2
REF HI: internal reference voltage select
0 = Internal reference voltage = 1.25V
1 = Internal reference voltage = 2.5V
bit 1
BUF EN: buffer enable
0 = Buffer disabled
1 = Buffer enabled
bit 0
BIT ORDER: set order bits are transmitted
0 = Most significant bit transmitted first
1 = Least significant bit transmitted first data is always shifted into the part most significant bit first.
Data is always shifted out of the part most significant byte first. This configuration bit only controls the
bit order within the byte of data that is shifted out.
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MUX (Address 01h) Multiplexer Control Register
Reset value = 01h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
PSEL3
PSEL2
PSEL1
PSEL0
NSEL3
NSEL2
NSEL1
NSEL0
bits 7-4
PSEL3: PSEL2: PSEL1: PSEL0: Positive channel select
0000 =
0001 =
0010 =
0011 =
AIN0
AIN1
AIN2
AIN3
0100
0101
0110
0111
=
=
=
=
AIN4
AIN5
AIN6
AIN7
0100
0101
0110
0111
=
=
=
=
AIN4
AIN5
AIN6
AIN7
1xxx = AINCOM (except when all bits are 1s)
1111 = Temperature sensor diode
bits 3-0
NSEL3: NSEL2: NSEL1: NSEL0: Negative channel select
0000 =
0001 =
0010 =
0011 =
AIN0
AIN1
AIN2
AIN3
1xxx = AINCOM (except when all bits are 1s)
1111 = Temperature sensor diode
ACR (Address 02h) Analog Control Register
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
BOCS
IDAC2R1
IDAC2R0
IDAC1R1
IDAC1R0
PGA2
PGA1
PGA0
bit 7
BOCS: Burnout current source
0 = Disabled
1 = Enabled
IDAC Current +
ǒ8RV Ǔǒ2
REF
RANGE*1
Ǔ(DAC CODE)
DAC
bits 6-5 IDAC2R1: IDAC2R0: Full-scale range select for IDAC2
00 =
01 =
10 =
11 =
Off
Range 1
Range 2
Range 3
bits 4-3 IDAC1R1: IDAC1R0: Full-scale range select for IDAC1
00 =
01 =
10 =
11 =
Off
Range 1
Range 2
Range 3
bits 2-0 PGA2: PGA1: PGA0: Programmable gain amplifier gain selection
000 =
001 =
010 =
011 =
22
1
2
4
8
100 =
101 =
110 =
111 =
16
32
64
128
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IDAC1 (Address 03h) Current DAC 1
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
IDAC1_7
IDAC1_6
IDAC1_5
IDAC1_4
IDAC1_3
IDAC1_2
IDAC1_1
IDAC1_0
The DAC code bits set the output of DAC1 from 0 to full-scale. The value of the full-scale current is set by this byte, VREF, RDAC, and the
DAC1 range bits in the ACR register.
IDAC2 (Address 04h) Current DAC 2
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
IDAC2_7
IDAC2_6
IDAC2_5
IDAC2_4
IDAC2_3
IDAC2_2
IDAC2_1
IDAC2_0
The DAC code bits set the output of DAC2 from 0 to full-scale. The value of the full-scale current is set by this byte, VREF, RDAC, and the
DAC2 range bits in the ACR register.
ODAC (Address 05h) Offset DAC Setting
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
SIGN
OSET6
OSET5
OSET4
OSET3
OSET2
OSET1
OSET0
bit 7
Offset sign
0 = Positive
1 = Negative
bits 6-0
V REF
2PGA
Offset +
NOTE:
ǒCode
Ǔ
127
The offset must be used after calibration or the calibration will nullify the effects.
DIO (Address 06h) Digital I/O
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
DIO7
DIO6
DIO5
DIO4
DIO3
DIO2
DIO1
DIO0
A value written to this register will appear on the digital I/O pins if the pin is configured as an output in the DIR register. Reading this
register will return the value of the digital I/O pins.
DIR (Address 07h) Direction control for digital I/O
Reset value = FFh.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
DIR7
DIR6
DIR5
DIR4
DIR3
DIR2
DIR1
DIR0
Each bit controls whether the Digital I/O pin is an output (= 0) or input (= 1). The default power-up state is as
inputs.
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DEC0 (Address 08h) Decimation Register (least significant 8 bits)
Reset value = 80h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
DEC07
DEC06
DEC05
DEC04
DEC03
DEC02
DEC01
DEC00
The decimation value is defined with 11 bits for a range of 20 to 2047. This register is the least significant eight bits. The three most
significant bits are contained in the M/DEC1 register.
M/DEC1 (Address 09h) Mode and Decimation Register
Reset value = 07h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
DRDY
U/B
SMODE1
SMODE0
Reserved
DEC10
DEC09
DEC08
bit 7
DRDY: Data ready (read-only)
This bit duplicates the state of the DRDY pin.
bit 6
U/B: Data format
0 = Bipolar
1 = Unipolar
U/B
ANALOG INPUT
DIGITAL OUTPUT
0
+FS
Zero
–FS
0x7FFFFF
0x000000
0x800000
1
+FS
Zero
–FS
0xFFFFFF
0x000000
0x000000
bits 5-4 SMODE1: SMODE0: Settling mode
00 =
01 =
10 =
11 =
bit 3
Auto
Fast-Settling filter
Sinc2 filter
Sinc3 filter
Reserved
This bit is not used in the ADS1216 and it is recommended that it be set to 0.
bits 2-0 DEC10: DEC09: DEC08: Most significant bits of the decimation value
24
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OCR0 (Address 0Ah) Offset Calibration Coefficient (least significant byte)
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
OCR07
OCR06
OCR05
OCR04
OCR03
OCR02
OCR01
OCR00
OCR1 (Address 0Bh) Offset Calibration Coefficient (middle byte)
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
OCR15
OCR14
OCR13
OCR12
OCR11
OCR10
OCR09
OCR08
OCR2 (Address 0Ch) Offset Calibration Coefficient (most significant byte)
Reset value = 00h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
OCR23
OCR22
OCR21
OCR20
OCR19
OCR18
OCR17
OCR16
FSR0 (Address 0Dh) Full-Scale Register (least significant byte)
Reset value = 24h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
FSR07
FSR06
FSR05
FSR04
FSR03
FSR02
FSR01
FSR00
FSR1 (Address 0Eh) Full-Scale Register (middle byte)
Reset value = 90h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
FSR15
FSR14
FSR13
FSR12
FSR11
FSR10
FSR09
FSR08
FSR2 (Address 0Fh) Full-Scale Register (most significant byte)
Reset value = 67h.
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
FSR23
FSR22
FSR21
FSR20
FSR19
FSR18
FSR17
FSR16
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COMMAND DEFINITIONS
The commands summarized in Table 4 control the operation of the ADS1216. All of the commands are
stand-alone except for the register reads and writes (RREG, WREG) which require a second command byte
plus data. Additional command and data bytes may be shifted in without delay after the first command byte. The
ORDER bit in the STATUS register (see the Register map section) sets the order of the bits within the output
data. CS must stay low during the entire command sequence.
Table 4. Command Definitions (1)
(1)
26
COMMAND
DESCRIPTION
1ST COMMAND BYTE
WAKEUP
Completes SYNC and exits standby mode
0000 0000 (00h)
RDATA
Read data
0000 0001 (01h)
2ND COMMAND BYTE
RDATAC
Read data continuously
0000 0011 (03h)
SDATAC
Stop read data continuously
0000 1111 (0Fh)
RREG
Read from REG rrr
0001 rrrr (1xh)
0000 nnnn
RRAM
Read from RAM bank aaa
0010 0aaa (2xh)
xnnn nnnn (number of bytes – 1)
CREG
Copy REG to RAM bank aaa
0100 0aaa (4xh)
CREGA
Copy REG to all RAM banks
0100 1000 (48h)
WREG
Write to REG rrr
0101 rrrr (5xh)
0000 nnnn
xnnn nnnn (number of bytes – 1)
WRAM
Write to RAM bank aaa
0110 0aaa (6xh)
CRAM
Copy RAM bank aaa to REG
1100 0aaa (Cxh)
CSRAMX
Calculate RAM bank aaa checksum
1101 0aaa (Dxh)
CSARAMX
Calculate all RAM banks checksum
1101 1000 (D8h)
CSREG
Calculate REG checksum
1101 1111 (DFh)
CSRAM
Calculate RAM bank aaa checksum
1110 0aaa (Exh)
CSARAM
Calculate all RAM banks checksum
1110 1000 (E8h)
SELFCAL
Offset and gain self-calibration
1111 0000 (F0h)
SELFOCAL
Offset self-calibration
1111 0001 (F1h)
SELFGCAL
Gain self-calibration
1111 0010 (F2h)
SYSOCAL
System offset calibration
1111 0011 (F3h)
SYSGCAL
System gain calibration
1111 0100 (F4h)
DSYNC
Synchronize the A/D conversion
1111 1100 (FCh)
SLEEP
Begin sleep mode
1111 1101 (FDh)
RESET
Reset to power-up values
1111 1110 (FEh)
WAKEUP
Completes SYNC and exits standby mode
1111 1111 (FFh)
n = number of registers to be read/written – 1. For example, to read/write three registers, set nnnn = 2 (0010). r = starting register
address for read/write commands.
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RDATA
Read Data
Description: Issue this command after DRDY goes low to read a single conversion result. After all 24 bits have
been shifted out on DOUT, DRDY goes high. It is not necessary to read back all 24 bits, but DRDY will then not
return high until new data is being updated. See the Timing Characteristics for the required delay between the
end of the RDATA command and the beginning of shifting data on DOUT: t6.
DRDY
DIN
0000 0001
MSB
DOUT
Mid-Byte
LSB
t6
SCLK
···
···
Figure 30. RDATA Command Sequence
RDATAC
Read Data Continuous
Description: Issue command after DRDY goes low to enter the Read Data Continuous mode. This mode
enables the continuous output of new data on each DRDY without the need to issue subsequent read
commands. After all 24 bits have been read, DRDY goes high. It is not necessary to read back all 24 bits, but
DRDY will then not return high until new data is being updated. This mode may be terminated by the Stop Read
Data Continuous command (STOPC). Because DIN is constantly being monitored during the Read Data
Continuous mode for the STOPC or RESET command, do not use this mode if DIN and DOUT are connected
together. See the Timing Characteristics for the required delay between the end of the RDATAC command and
the beginning of shifting data on DOUT: t6.
DRDY
DIN
0000 0011
t6
24 Bits
DOUT
24 Bits
Figure 31. RDATAC Command Sequence
On the following DRDY, shift out data by applying SCLKs. The Read Data Continuous mode terminates if
input_data equals the STOPC or RESET command in any of the three bytes on DIN.
DRDY
DIN
DOUT
input_data
input_data
input_data
MSB
Mid-Byte
LSB
Figure 32. DIN and DOUT Command Sequence During Read Continuous mode
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STOPC
Stop Read Data Continuous
Description: Ends the continuous data output mode; refer to RDATAC in the Command Definitions section. The
command must be issued after DRDY goes low and completed before DRDY goes high.
DRDY
DIN
000 1111
Figure 33. STOPC Command Sequence
RREG
Read from Registers
Description: Output the data from up to 16 registers starting with the register address specified as part of the
command. The number of registers read will be one plus the second byte of the command. If the count exceeds
the remaining registers, the addresses will wrap back to the beginning.
1st Command Byte: 0001 rrrr where rrrr is the address of the first register to read.
2nd Command Byte: 0000 nnnn where nnnn is the number of bytes to read – 1. See the Timing Characteristics
for the required delay between the end of the RREG command and the beginning of shifting data on DOUT: t6.
DIN
0001 0001
0000 0001
1st Command 2nd Command
Byte
Byte
t6
DOUT
MUX
ADCON
Data
Byte
Data
Byte
Figure 34. RREG Command Example: Read Two Registers Starting from Regiater 01h (multiplexer)
RRAM
Read from RAM
Description:This command allows for the direct reading of the RAM contents. All reads begin at the specified
starting RAM bank. More than one bank can be read out in a single read operation. The reads will wrap around
to the first bank if there is more data to be retrieved when the last bank is completely read. See the Timing
Characteristics for the required delay between the end of the RRAM command and the beginning of shifting data
on DOUT: t6.
1st Command Byte: 0010 0aaa where aaa is the starting RAM bank for the read.
2nd Command Byte: 0nnn nnnn where nnn nnnn is the number of bytes to be read – 1.
DIN
0010 0001
0000 1111
t6
DOUT
Bank 1,
Byte 0
Bank 1,
Byte 1
RAM Data
Figure 35. RRAM Command Example: Read 16 Bytes Starting from Bank 1
28
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CREG
Copy Registers to RAM Bank
Description: This command copies the registers to the selected RAM bank. Do not issue additional commands
while the copy operation is underway.
1st Command byte: 0100 0aaa where aaa is the RAM bank that will be updated with a copy of the registers.
CREGA
Copy Registers to All RAM Banks
Description: This command copies the registers to all RAM banks. Do not issue additional commands while the
copy operation is underway.
WREG
Write to Register
Description: Write to the registers starting with the register specified as part of the command. The number of
registers that will be written is one plus the value of the second byte in the command.
1st Command Byte: 0101 rrrr where rrrr is the address to the first register to be written.
2nd Command Byte: 0000 nnnn where nnnn is the number of bytes to be written – 1.
Data Byte(s): data to be written to the registers.
DIN
0101 0011
DRATE Data
0000 0001
1st Command 2nd Command
Byte
Byte
Data
Byte
IO Data
Data
Byte
Figure 36. WREG Command Example: Write Two Registers Starting from 03h (DRATE)
WRAM
Write to RAM
Description: This command allows for direct writing to the RAM. All writes begin at the specified starting RAM
bank. More than one bank can be written in a single write operation. The writes will wrap around to the first bank
if there is more data to be written when the last bank is completely written. See the Timing Characteristics for
the required delay between the end of the RRAM command and the beginning of shifting data on DOUT: t6.
1st Command Byte: 0010 0aaa where aaa is the starting RAM bank for the write.
2nd Command Byte: 0nnn nnnn where nnn nnnn is the number of bytes to be written – 1.
DIN
0110 0001
Bank 1,
Byte 0
0000 1111
Bank 1,
Byte 1
tx
RAM Data
Figure 37. WRAM Command Example: Write 16 Bytes Starting at Bank 1
CRAM
Copy Selected RAM Bank to Registers
Description: This command copies the selected RAM bank to the registers. This action will overwrite all
previous register settings. Do not issue additional commands while this copy operation is underway.
1st Command Byte: 1100 0aaa where aaa is the selected RAM bank.
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CSRAM
Calculate Checksum for Selected RAM Bank
Description: This command calculates the checksum for the selected RAM bank. The checksum is calculated
as the sum of all the bytes in the registers with the carry ignored. Do not issue any additional commands while
the checksum is being calculated.
CSRAMX
Calculate Checksum for Selected RAM Bank,
Ignoring Certain Bits
Description: This command calculates the checksum of the selected RAM bank. The checksum is calculated as
a sum of all the bytes in the RAM bank with the carry ignored. The ID, DRDY, and DIO bits are masked and are
not included in the checksum calculation. Do not issue any additional commands while the checksum is being
calculated.
CSARAM
Calculate Checksum for all RAM Banks
Description: This command calculates the checksum for all RAM banks. The checksum is calculated as a sum
of all the bytes in the RAM bank with the carry ignored. Do not issue any additional commands while the
checksum is being calculated.
Calculate Checksum for all RAM Banks, Ignoring
Certain Bits
CSARAMX
Description: This command calculates the checksum for all RAM banks. The checksum is calculated as a sum
of all the bytes in the RAM bank with the carry ignored. The ID, DRDY, and DIO bits are masked and are not
included in the checksum calculation. Do not issue any additional commands while the checksum is being
calculated.
CSREG
Calculate Checksum for the Registers
Description: This command calculates the checksum for the registers. The checksum is calculated as a sum of
all the bytes in the registers with the carry ignored. The ID, DRDY, and DIO bits are masked and are not
included in the checksum calculation. Do not issue any additional commands while the checksum is being
calculated.
See the Timing Characteristics for the required delay between the end of the checksum commands and the
beginning of shifting data on DOUT: t6. Note that this time is dependent on the specific checksum command used.
DIN
0000 0011
t6
DOUT
24 Bits
Figure 38. Checksum Command Sequence
SYSOCAL
System Offset Calibration
Description: Performs a system offset calibration. The Offset Calibration Register (OFC) is updated after this
operation. DRDY goes high at the beginning of the calibration. It goes low after the calibration completes and
settled data is ready. Do not send additional commands after issuing this command until DRDY goes low
indicating that the calibration is complete.
30
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SYSGCAL
System Gain Calibration
Description: Performs a system gain calibration. The Full-Scale Calibration Register (FSC) is updated after this
operation. DRDY goes high at the beginning of the calibration. It goes low after the calibration completes and
settled data is ready. Do not send additional commands after issuing this command until DRDY goes low
indicating that the calibration is complete.
DSYNC
Synchronize the A/D Conversion
Description: This command synchronizes the A/D conversion. To use, first shift in the command. Then shift in
the WAKEUP command. Synchronization occurs on the first CLKIN rising edge after the first SCLK used to shift
in the WAKEUP command.
DIN
1111 1100
(SYNC)
SCLK
···
CLKIN
0000 0000
(WAKEUP)
···
···
···
Synchronization Occurs Here
Figure 39. DSYNC Command Sequence
SLEEP
Sleep Mode
Description: This command puts the ADS1216 into a Sleep mode. After issuing the SLEEP command, make
sure there is no more activity on SCLK while CS is low because this will interrupt Sleep mode. If CS is high,
SCLK activity is allowed during Sleep mode. To exit Sleep mode, issue the WAKEUP command.
DIN
1111 1101
(SLEEP)
0000 0000
(WAKEUP)
SCLK
Normal Mode
Sleep Mode
Normal Mode
Figure 40. SLEEP Command Sequence
WAKEUP
Complete Synchronization or Exit Sleep Mode
Description: Used in conjunction with the SYNC and STANDBY commands. Two values (all zeros or all ones)
are available for this command.
RESET
Reset Registers to Default Values
Description: Returns all registers to their default values. This command will also stop the Read Data
Continuous mode. While in the Read Data Continuous mode, the RESET command must be issued after DRDY
goes low and complete before DRDY returns high.
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DEFINITIONS
Analog Input Voltage—the voltage at any one
analog input relative to AGND.
Analog Input Differential Voltage—given by the
following equation: (AIN+) – (AIN–). Thus, a positive
digital output is produced whenever the analog input
differential voltage is positive, while a negative digital
output is produced whenever the differential is
negative.
For example, when the converter is configured with a
2.5V reference and placed in a gain setting of 1, the
positive full-scale output is produced when the
analog input differential is 2.5V. The negative
full-scale output is produced when the differential is
–2.5V. In each case, the actual input voltages must
remain within the AGND to AVDD range.
Conversion Cycle—the term conversion cycle
usually refers to a discrete A/D conversion operation,
such as that performed by a successive
approximation converter. As used here, a conversion
cycle refers to the tDATA time period. However, each
digital output is actually based on the modulator
results from several tDATA time periods.
FILTER SETTING
MODULATOR RESULTS
Fast Settling
1 tDATA Time Period
Sinc2
2 tDATA Time Period
Sinc3
3 tDATA Time Period
Data Rate—the rate at which conversions are
completed. See definition for fDATA.
Decimation Ratio—defines the ratio between the
output of the modulator and the output Data Rate.
Valid values for the Decimation Ratio are from 20 to
2047. Larger Decimation Ratios will have lower
noise.
Effective Resolution—the effective resolution of the
ADS1216 in a particular configuration can be
expressed in two different units: bits rms (referenced
to output) and VRMS (referenced to input). Computed
directly from the converter output data, each is a
statistical calculation. The conversion from one to the
other is shown below.
Effective number of bits (ENOB) or effective
resolution is commonly used to define the usable
resolution of the A/D converter. It is calculated from
empirical data taken directly from the device. It is
typically determined by applying a fixed known signal
source to the analog input and computing the
standard deviation of the data sample set. The rms
noise defines the ±σ interval about the sample mean.
32
The data from the A/D converter is output as codes,
which then can be easily converted to other units,
such as ppm or volts. The equations and table below
show the relationship between bits or codes, ppm,
and volts.
−20 log(ppm)
ENOB +
6.02
BITS rms
BIPOLAR VRMS
ǒ
Ǔ
ǒ Ǔ
2V REF
PGA
10ǒ
UNIPOLAR VRMS
V REF
PGA
Ǔ
Ǔ
10ǒ6.02ER
20
24
298nV
149nV
22
1.19µV
597nV
20
4.77µV
2.39µV
18
19.1µV
9.55µV
16
76.4µV
38.2µV
14
505µV
152.7µV
12
1.22mV
610µV
6.02ER
20
fDATA—the frequency of the digital output data
produced by the ADS1216. fDATA is also referred to
as the data rate.
f DATA +
f
f
ǒDecimation
Ǔ + ǒmfactor Decimation
Ǔ
Ratio
Ratio
MOD
OSC
fMOD—the frequency or speed at which the modulator
of the ADS1216 is running. This rate depends on the
SPEED bit as shown below:
SPEED BIT
fMOD
0
fOSC/128
1
fOSC/256
fOSC—the frequency of the crystal input signal at the
XIN input of the ADS1216.
fSAMP—the frequency, or switching speed, of the
input sampling capacitor. The value is given by one
of the following equations:
PGA SETTING
SAMPLING FREQUENCY
1, 2, 4, 8
f SAMP +
f OSC
mfactor
8
f SAMP +
2f OSC
mfactor
16
f SAMP +
8f OSC
mfactor
32
f SAMP +
16f OSC
mfactor
64, 128
f SAMP +
16f OSC
mfactor
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SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
Filter Selection—the ADS1216 uses a (sinx/x) filter
or sinc filter. There are three different sinc filters that
can be selected. A Fast-Settling filter will settle in
one tDATA cycle. The Sinc2 filter will settle in two
cycles and have lower noise. The Sinc3 will achieve
lowest noise and higher number of effective bits, but
requires three cycles to settle. The ADS1216 will
operate with any one of these filters, or it can
operate in an auto mode, where it will first select the
Fast-Settling filter after a new channel is selected for
two readings and will then switch to Sinc2 for one
reading, followed by Sinc3 from then on.
Full-Scale Range (FSR)—as with most A/D
converters, the full-scale range of the ADS1216 is
defined as the input, which produces the positive
full-scale digital output minus the input, which
produces the negative full-scale digital output. The
full-scale range changes with gain setting; see
Table 5.
For example, when the converter is configured with a
2.5V reference and is placed in a gain setting of 2,
the full-scale range is: [1.25V (positive full-scale) –
(–1.25V (negative full-scale))] = 2.5V.
Least Significant Bit (LSB) Weight—this is the
theoretical amount of voltage that the differential
voltage at the analog input would have to change in
order to observe a change in the output data of one
least significant bit. It is computed as shown in
Equation 1:
Full−Scale Range
LSB Weight +
2N
(1)
where N is the number of bits in the digital output.
tDATA—the inverse of fDATA, or the period between
each data output.
Table 5. Full-Scale Range vs PGA Setting
5V SUPPLY ANALOG INPUT (1)
GAIN
SETTING
(1)
(2)
FULL-SCALE
RANGE
DIFFERENTIAL
INPUT
VOLTAGES (2)
PGA OFFSET
RANGE
1
5V
±2.5V
±1.25V
2
2.5V
±1.25V
±0.625V
4
1.25V
±0.625V
±312.5mV
8
0.625V
±312.5mV
±156.25mV
16
312.5mV
±156.25mV
±78.125mV
34
156.25mV
±78.125mV
±39.0625mV
64
78.125mV
±39.0625mV
±19.531mV
128
39.0625mV
±19.531mV
±9.766mV
GENERAL EQUATIONS
FULL-SCALE
RANGE
DIFFERENTIAL
INPUT
VOLTAGES (2)
PGA SHIFT
RANGE
2V REF
PGA
" VREF
PGA
" VREF
2PGA
With a 2.5V reference.
The ADS1216 allows common-mode voltage as long as the absolute input voltage on AIN+ or AIN– does not go below AGND or above
AVDD.
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33
ADS1216
www.ti.com
SBAS171D – NOVEMBER 2000 – REVISED SEPTEMBER 2006
Changes from C Revision (May 2006) to D Revision ..................................................................................................... Page
•
•
34
Added title for Table 1......................................................................................................................................................... 16
Changed 11 registers to 16 registers in Description text of RREG section in Command Definitions. ............................... 28
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PACKAGE OPTION ADDENDUM
www.ti.com
14-Oct-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
Samples
(4/5)
(6)
ADS1216Y/250
ACTIVE
TQFP
PFB
48
250
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 85
ADS1216Y
Samples
ADS1216Y/2K
ACTIVE
TQFP
PFB
48
2000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 85
ADS1216Y
Samples
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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