ADS1131
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SBAS449C – JULY 2009 – REVISED OCTOBER 2013
18-Bit Analog-to-Digital Converter
for Bridge Sensors
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FEATURES
DESCRIPTION
•
•
•
•
•
•
•
•
The ADS1131 is a precision, 18-bit analog-to-digital
converter (ADC). With an onboard, low-noise
amplifier, onboard oscillator, precision 18-bit deltasigma (ΔΣ) ADC, and bridge power switch, the
ADS1131 provides a complete front-end solution for
bridge sensor applications including weigh scales,
strain gauges, and load cells.
1
2
•
•
•
•
•
Complete Front-End for Bridge Sensors
Available in an SO Package
Internal Amplifier, Gain of 64
Internal Oscillator
Low-Side Power Switch for Bridge Sensor
18-Bit Noise-Free Resolution
Selectable 10SPS or 80SPS Data Rates
Simultaneous 50Hz and 60Hz Rejection at
10SPS
External Voltage Reference up to 5V for
Ratiometric Measurements
Simple, Pin-Driven Control
Two-Wire Serial Digital Interface
Supply Range: 3V to 5.3V
–40°C to +85°C Temperature Range
The low-noise amplifier has a gain of 64, supporting a
full-scale differential input of ±39mV. The ΔΣ ADC
has 18-bit effective resolution and is comprised of a
third-order modulator and fourth-order digital filter.
Two data rates are supported: 10SPS (with both
50Hz and 60Hz rejection) and 80SPS. The ADS1131
can be put into a low-power standby mode or shut off
completely in power-down mode.
The ADS1131 is controlled by dedicated pins; there
are no digital registers to program. Data are output
over an easily-isolated serial interface that connects
directly to the MSP430 and other microcontrollers.
APPLICATIONS
•
•
•
•
The ADS1131 is available in an SO-16 package and
is specified from –40°C to +85°C.
Weigh Scales
Strain Gauges
Load Cells
Industrial Process Control
AVDD
CAP
CAP
VREFP
VREFN
DVDD
PDWN
AINP
DRDY/DOUT
G = 64
DS ADC
AINN
Internal
Oscillator
SCLK
SPEED
SW
GND
1
2
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.
All 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 © 2009–2013, Texas Instruments Incorporated
ADS1131
SBAS449C – JULY 2009 – REVISED OCTOBER 2013
www.ti.com
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.
PACKAGE AND ORDERING INFORMATION (1)
(1)
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or visit the
device product folder at www.ti.com.
ABSOLUTE MAXIMUM RATINGS (1)
Over operating free-air temperature range, unless otherwise noted.
ADS1131
UNIT
AVDD to GND
–0.3 to +6
V
DVDD to GND
–0.3 to +6
V
100, momentary
mA
10, continuous
mA
Analog input voltage to GND
–0.3 to AVDD + 0.3
V
Digital input voltage to GND
–0.3 to DVDD + 0.3
V
Input current
Maximum junction temperature
+150
°C
Operating temperature range
–40 to +85
°C
Storage temperature range
–60 to +150
°C
(1)
2
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated is not implied. Exposure to absolutemaximum-rated conditions for extended periods may affect device reliability.
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ELECTRICAL CHARACTERISTICS
Minimum/maximum limit specifications apply from –40°C to +85°C. Typical specifications at +25°C.
All specifications at AVDD = DVDD = VREFP = +5V, and VREFN = GND, unless otherwise noted.
ADS1131
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
ANALOG INPUTS
Full-scale input voltage (AINP – AINN)
±0.5VREF/64
V
VREF = AVDD = 5V
±39.0
mV
VREF = AVDD = 3V
±23.4
mV
Common-mode input range
GND + 1.5V
Differential input current
AVDD – 1.5V
V
±2
nA
LOW-SIDE POWER SWITCH
On-resistance (RON)
Ω
AVDD = 5V, ISW = 30mA
3.5
5
AVDD = 3V, ISW = 30mA
4
7
Ω
30
mA
Current through switch
SYSTEM PERFORMANCE
Resolution
No missing codes
Data rate
18
Bits
SPEED = high
80
SPS
SPEED = low
10
SPS
Digital filter settling time
Full settling
4
Conversions
Integral nonlinearity (INL)
Differential input, end-point fit
±8
ppm
Input offset error
10
μV
Input offset drift
±15
nV/°C
Gain error
1
%
Gain drift
±4
ppm/°C
dB
Normal-mode rejection
fIN = 50Hz or 60Hz ±1Hz, fDATA = 10SPS
90
Common-mode rejection
At dc
110
dB
fDATA = 10SPS, AVDD = VREF = 5V
1
LSB
fDATA = 80SPS, AVDD = VREF = 5V
1.7
LSB
fDATA = 10SPS, AVDD = VREF = 5V
300
nV
fDATA = 80SPS, AVDD = VREF = 5V
500
nV
At dc
100
dB
Noise (peak-to-peak)
Power-supply rejection
VOLTAGE REFERENCE INPUT
Voltage reference input (VREF)
AVDD + 0.1V
V
Negative reference input (VREFN)
VREF = VREFP – VREFN
AGND – 0.1
1.5
VREFP – 1.5
V
Positive reference input (VREFP)
VREFN + 1.5
AVDD + 0.1
Voltage reference input current
AVDD
V
10
nA
DIGITAL INPUT/OUTPUT (DVDD = 2.7V to 5.3V)
Logic levels
VIH
0.8 DVDD
DVDD + 0.1
V
VIL
GND
0.2 DVDD
V
VOH
IOH = 500μA
VOL
IOL = 500μA
Input leakage
DVDD – 0.4
0 < VDIGITAL INPUT < DVDD
Serial clock input frequency (fSCLK)
V
0.2 DVDD
V
±10
μA
5
MHz
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ELECTRICAL CHARACTERISTICS (continued)
Minimum/maximum limit specifications apply from –40°C to +85°C. Typical specifications at +25°C.
All specifications at AVDD = DVDD = VREFP = +5V, and VREFN = GND, unless otherwise noted.
ADS1131
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNIT
POWER SUPPLY
Power-supply voltage (AVDD, DVDD)
Analog supply current
Digital supply current
Power dissipation, total
3
5.3
V
Normal mode, AVDD = 3V
900
μA
Normal mode, AVDD = 5V
900
μA
Standby mode
0.1
μA
Power-down
0.1
μA
Normal mode, DVDD = 3V
60
μA
Normal mode, DVDD = 5V
95
μA
Standby mode, SCLK = high, DVDD = 3V
45
μA
Standby mode, SCLK = high, DVDD = 5V
65
μA
Power-down
0.2
μA
Normal mode, AVDD = DVDD = 3V
2.9
mW
Normal mode, AVDD = DVDD = 5V
5.0
mW
TEMPERATURE
Operating temperature range
–40
+85
°C
Specified temperature range
–40
+85
°C
THERMAL INFORMATION
ADS1131D
THERMAL METRIC (1)
D
UNITS
16 PINS
θJA
Junction-to-ambient thermal resistance
133.8
θJC(top)
Junction-to-case(top) thermal resistance
71.4
θJB
Junction-to-board thermal resistance
60.0
ψJT
Junction-to-top characterization parameter
17.4
ψJB
Junction-to-board characterization parameter
53.3
θJC(bottom)
Junction-to-case(bottom) thermal resistance
n/a
(1)
4
°C/W
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
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PIN CONFIGURATION
D PACKAGE
SO-16
(TOP VIEW)
DVDD
1
16
DRDY/DOUT
GND
2
15
SCLK
GND
3
14
PDWN
SPEED
4
13
AVDD
CAP
5
12
SW
CAP
6
11
GND
AINP
7
10
VREFP
AINN
8
9
VREFN
PIN DESCRIPTIONS
NAME
TERMINAL
ANALOG/DIGITAL
INPUT/OUTPUT
DVDD
1
Digital
Digital power supply
GND
2
Supply
Ground for digital and analog supplies
GND
3
Supply
Ground for digital and analog supplies
DESCRIPTION
Data rate select:
SPEED
4
CAP
5
CAP
AINP
Digital input
SPEED
DATA RATE
0
10SPS
1
80SPS
Analog
Gain amplifier bypass capacitor connection
6
Analog
Gain amplifier bypass capacitor connection
7
Analog input
Positive analog input
AINN
8
Analog input
Negative analog input
VREFN
9
Analog input
Negative reference input
VREFP
10
Analog input
Positive reference input
GND
11
Supply
Ground for digital and analog supplies
SW
12
Analog
Low-side power switch
AVDD
13
Supply
Analog power supply
PDWN
14
Digital input
Power-down: holding this pin low powers down the entire converter and resets the ADC.
SCLK
15
Digital input
Serial clock: clock out data on the rising edge. Also used to initiate Standby mode. See the Standby
Mode section for more details.
DRDY/DOUT
16
Digital output
Dual-purpose output:
Data ready: indicates valid data by going low.
Data output: outputs data, MSB first, on the first rising edge of SCLK.
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OVERVIEW
The ADS1131 is a precision, 18-bit ADC that includes
a low-noise PGA, internal oscillator, third-order deltasigma (ΔΣ) modulator, and fourth-order digital filter.
The ADS1131 provides a complete front-end solution
for bridge sensor applications such as weigh scales,
strain gauges, and pressure sensors.
Data can be output at 10SPS for excellent 50Hz and
60Hz rejection, or at 80SPS when higher speeds are
needed. The ADS1131 is easy to configure, and all
digital control is accomplished through dedicated
pins; there are no registers to program. A simple twowire serial interface retrieves the data.
–39mV to +39mV, and the unipolar input ranges from
0mV to +39mV. The inputs of the ADS1131 are
protected with internal diodes connected to the
power-supply rails. These diodes clamp the applied
signal to prevent it from damaging the input circuitry.
CAP
450W
RINT
AINP
18pF
A1
R
Gain = 1
F1
R1
ANALOG INPUTS (AINP, AINN)
A3
RF2
The input signal to be measured is applied to the
input pins AINP and AINN. The ADS1131 accepts
differential input signals, but can also measure
unipolar signals. When measuring unipolar (or singleended signals) with respect to ground, connect the
negative input (AINN) to ground and connect the
input signal to the positive input (AINP). Note that
when the ADS1131 is configured this way, only half
of the converter full-scale range is used, because
only positive digital output codes are produced.
ADC
RINT
A2
450W
AINN
18pF
CAP
Figure 1. Simplified Diagram of the Amplifier
LOW-NOISE AMPLIFIER
External Capacitor
The ADS1131 features a low-drift, low-noise amplifier
that provides a complete front-end solution for bridge
sensors. A simplified diagram of the amplifier is
shown in Figure 1. It consists of two chopperstabilized amplifiers (A1 and A2) and three accurately
matched resistors (R1, RF1, and RF2) that construct a
differential front-end stage with a gain of 64, followed
by gain stage A3 (Gain = 1). The inputs are equipped
with an EMI filter, as shown in Figure 1. The cutoff
frequency of the EMI filter is 20MHz. By using AVDD
as the reference input, the bipolar input ranges from
An external capacitor (CEXT) across the ADS1131 two
CAP pins combines with the internal resistor RINT (onchip) to create a low-pass filter. The recommended
value for CEXT is 0.1μF which provides a corner
frequency of 720Hz. This low-pass filter serves two
purposes. First, the input signal is bandlimited to
prevent aliasing by the ADC and to filter out the highfrequency noise. Second, it attenuates the chopping
residue from the amplifier to improve temperature drift
performance. NPO or C0G capacitors are
recommended. For optimal performance, place the
external capacitor very close to the CAP pins.
6
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VOLTAGE REFERENCE INPUTS
(VREFP, VREFN)
LOW-SIDE POWER SWITCH (SW)
The voltage reference used by the modulator is
generated from the voltage difference between
VREFP and VREFN: VREF = VREFP – VREFN. The
reference inputs use a structure similar to that of the
analog inputs. In order to increase the reference input
impedance, a switching buffer circuitry is used to
reduce the input equivalent capacitance. The
reference drift and noise impact ADC performance. In
order to achieve best results, pay close attention to
the reference noise and drift specifications. A
simplified diagram of the circuitry on the reference
inputs is shown in Figure 2. The switches and
capacitors can be modeled approximately using an
effective impedance of:
ZEFF = 500MW
VREFP
The ADS1131 incorporates an internal switch for use
with an external bridge sensor, as shown in Figure 3.
The switch can be used in a return path for the bridge
power. By opening the switch, power dissipation in
the bridge is eliminated.
The switch is controlled by the ADS1131 conversion
status. During normal conversions, the switch is
closed (the SW pin is connected to GND). During
standby or power-down modes, the switch is opened
(the SW pin is high impedance). When using the
switch, it is recommended that the negative reference
input (VREFN) be connected directly to the bridge
ground terminal, as shown in Figure 3 for best
performance.
+VDD
VREFN
ADS1131
VREFP
AVDD
AVDD
Bridge
Sensor
AINP
ESD
Protection
CBUF
AINN
ZEFF = 500MW
VREFN
SW
Figure 2. Simplified Reference Input Circuitry
GND
ESD diodes protect the reference inputs. To prevent
these diodes from turning on, make sure the voltages
on the reference pins do not go below GND by more
than 100mV, and likewise, do not exceed AVDD by
100mV:
CLOCK SOURCE
GND – 100mV < (VREFP or VREFN) < AVDD +
100mV
The ADS1131 uses an internal oscillator. No external
clock circuitry is required.
Figure 3. Low-Side Power Switch
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FREQUENCY RESPONSE
0
Data Rate = 10SPS
4
-50
Gain (dB)
The ADS1131 uses a sinc digital filter with the
frequency response. The frequency response repeats
at multiples of the modulator sampling frequency of
76.8kHz. The overall response is that of a low-pass
filter with a –3dB cutoff frequency of 3.32Hz with the
SPEED pin tied low (10SPS data rate) and 11.64Hz
with the SPEED pin tied high (80SPS data rate).
-100
To help see the response at lower frequencies,
Figure 4(a) illustrates the nominal response out to
100Hz, when the data rate = 10SPS. Notice that
signals at multiples of 10Hz are rejected, and
therefore simultaneous rejection of 50Hz and 60Hz is
achieved.
-150
0
20
30
40
50
60
70
80
90
100
Frequency (Hz)
(a)
The benefit of using a sinc4 filter is that every
frequency notch has four zeros on the same location.
This response, combined with the low drift internal
oscillator, provides an excellent normal-mode
rejection of line-cycle interference.
-50
Data Rate = 10SPS
Gain (dB)
Figure 4(b) zooms in on the 50Hz and 60Hz notches
with the SPEED pin tied low (10SPS data rate).
10
-100
-150
46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
Frequency (Hz)
(b)
Figure 4. Nominal Frequency Response Out To
100Hz
8
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Table 1. Data Rate Settings
SETTLING TIME
Fast changes in the input signal require time to settle.
For example, an external multiplexer in front of the
ADS1131 can generate abrupt changes in input
voltage by simply switching the multiplexer input
channels. These sorts of changes in the input require
four data conversion cycles to settle. When
continuously converting, five readings may be
necessary in order to settle the data. If the change in
input occurs in the middle of the first conversion, four
more full conversions of the fully-settled input are
required to obtain fully-settled data. Discard the first
four readings because they contain only partiallysettled data. Figure 5 illustrates the settling time for
the ADS1131.
SPEED PIN
DATA RATE
0
10SPS
1
80SPS
DATA FORMAT
The ADS1131 outputs 18 bits of data in binary twos
complement format. The least significant bit (LSB)
has a weight of (0.5VREF/64)(217 – 1). The positive
full-scale input produces an output code of 1FFFFh
and the negative full-scale input produces an output
code of 20000h. The output clips at these codes for
signals exceeding full-scale. Table 2 summarizes the
ideal output codes for different input signals.
Table 2. Ideal Output Code vs Input Signal
DATA RATE
The ADS1131 data rate is set by the SPEED pin, as
shown in Table 1. When SPEED is low, the data rate
is nominally 10SPS. This data rate provides the
lowest noise, and also has excellent rejection of both
50Hz and 60Hz line-cycle interference. For
applications requiring fast data rates, setting SPEED
high selects a data rate of nominally 80SPS.
INPUT SIGNAL VIN
(AINP – AINN)
IDEAL OUTPUT
≥ +0.5VREF/64
1FFFFh
(+0.5VREF/64)/(217 – 1)
00001h
0
00000h
(–0.5VREF/64)/(217 – 1)
3FFFFh
≤ –0.5VREF/64
20000h
1. Excludes effects of noise, INL, offset, and gain
errors.
Abrupt Change in VIN
VIN
Start of
Conversion
DRDY/DOUT
1st Conversion;
includes
unsettled VIN.
2nd Conversion;
VIN settled, but
digital filter
unsettled.
3rd Conversion;
VIN settled, but
digital filter
unsettled.
4th Conversion;
VIN settled, but
digital filter
unsettled.
5th Conversion;
VIN and digital
filter both
settled.
Conversion
Time
Figure 5. Settling Time in Continuous Conversion Mode
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DATA READY/DATA OUTPUT (DRDY/DOUT)
DATA RETRIEVAL
This digital output pin serves two purposes. First, it
indicates when new data are ready by going low.
Afterwards, on the first rising edge of SCLK, the
DRDY/DOUT pin changes function and begins
outputting the conversion data, most significant bit
(MSB) first. Data are shifted out on each subsequent
SCLK rising edge. After all 18 bits have been
retrieved, the pin can be forced high with an
additional SCLK. It then stays high until new data are
ready. This configuration is useful when polling on the
status of DRDY/DOUT to determine when to begin
data retrieval.
The ADS1131 continuously converts the analog input
signal. To retrieve data, wait until DRDY/DOUT goes
low, as shown in Figure 6. After DRDY/DOUT goes
low, begin shifting out the data by applying SCLKs.
Data are shifted out MSB first. It is not required to
shift out all 18 bits of data, but the data must be
retrieved before new data are updated (within tCONV)
or else the data will be overwritten. Avoid data
retrieval during the update period (tUPDATE). If only 18
SCLKs have been applied, DRDY/DOUT remains at
the state of the last bit shifted out until it is taken high
(see tUPDATE), indicating that new data are being
updated. To avoid having DRDY/DOUT remain in the
state of the last bit, the 19th SCLK can be applied to
force DRDY/DOUT high, as shown in Figure 7. This
technique is useful when a host controlling the device
is polling DRDY/DOUT to determine when data are
ready.
SERIAL CLOCK INPUT (SCLK)
This digital input shifts serial data out with each rising
edge. This input has built-in hysteresis, but care
should still be taken to ensure a clean signal. Glitches
or slow-rising signals can cause unwanted additional
shifting. For this reason, it is best to make sure the
rise and fall times of SCLK are both less than 50ns.
Data
New Data Ready
Data Ready
MSB
DRDY/DOUT
17
LSB
16
15
0
tPD
tHT
tDS
tSCLK
tUPDATE
1
SCLK
18
tSCLK
tCONV
Figure 6. 18-Bit Data Retrieval Timing
SYMBOL
tDS
tSCLK
tPD
(1)
tHT (1)
tUPDATE
tCONV
DESCRIPTION
MIN
DRDY/DOUT low to first SCLK rising edge
SCLK positive or negative pulse width
TYP
ns
ns
50
20
ns
ns
90
μs
SPEED = 1
12.5
ms
SPEED = 0
100
ms
Data updating: no readback allowed
Conversion time (1/data rate)
UNITS
100
SCLK rising edge to new data bit valid: propagation delay
SCLK rising edge to old data bit valid: hold time
MAX
0
(1) Minimum required from simulation.
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STANDBY MODE
When tSTANDBY has passed with SCLK held high,
Standby mode activates. DRDY/DOUT stays high
when Standby mode begins. SCLK must remain high
to stay in Standby mode. To exit Standby mode
(wakeup), set SCLK low. The first data after exiting
Standby mode are valid.
Standby
mode
dramatically
reduces
power
consumption by shutting down most of the circuitry. In
Standby mode, the entire analog circuitry is powered
down and only the clock source circuitry is awake to
reduce the wake-up time from the Standby mode. To
enter Standby mode, simply hold SCLK high after
DRDY/DOUT goes low; see Figure 8. Standby mode
can be initiated at any time during readback; it is not
necessary to retrieve all 18 bits of data beforehand.
Data
Data Ready
New Data Ready
DRDY/DOUT
17
16
15
0
1
SCLK
18
19
19th SCLK to Force DRDY/DOUT High
Figure 7. Data Retrieval with DRDY/DOUT Forced High Afterwards
Data Ready
Standby Mode
DRDY/DOUT
SCLK
17
16
15
1
0
Start Conversion
17
18
tDSS
tSTANDBY
tS_RDY
Figure 8. Standby Mode Timing (Can be used for single conversions)
SYMBOL
DESCRIPTION
tDSS (1)
SCLK high after DRDY/DOUT
goes low to activate Standby
mode
tSTANDBY
Standby mode activation time
tS_RDY
(1)
MAX
UNITS
SPEED = 1
MIN
12.44
ms
SPEED = 0
99.94
ms
SPEED = 1
0.0125
SPEED = 0
0.1
Data ready after exiting Standby SPEED = 1
mode
SPEED = 0
TYP
s
s
No change (typical time required)
ms
401.8
ms
(1) Based on an ideal internal oscillator.
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POWER-DOWN MODE
Power-Down mode shuts down the entire ADC
circuitry and reduces the total power consumption
close to zero. To enter Power-Down mode, simply
hold the PDWN pin low.
Power-Down mode also resets the entire circuitry.
Power-Down mode can be initiated at any time during
readback; it is not necessary to retrieve all 18 bits of
data beforehand. Figure 9 shows the wake-up timing
from Power-Down mode.
Start
Conversion
Power-Down Mode
tPDWN
Data Ready
CLK Source
Wakeup
PDWN
DRDY/DOUT
tTS_RDY
tWAKEUP
SCLK
Figure 9. Wake-Up Timing from Power-Down Mode
SYMBOL
tWAKEUP
(1)
tPDWN (1)
DESCRIPTION
MIN
Wake-up time after Power-Down mode
PDWN pulse width
(1)
Based on an ideal internal oscillator.
12
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26
TYP
UNITS
7.95
μs
μs
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APPLICATION EXAMPLE
Weigh Scale System
Figure 10 shows a typical ADS1131 application as part of a weigh scale system.
2.7V to 5.3V
3V
(1)
1 mF
13
AVDD
10
5
-
VREFP
CAP
DRDY/DOUT
0.1mF
6
SCLK
CAP
+
ADS1131
7
8
VDD
DVDD
(2)
Load
Cell
(1)
1mF
1
PDWN
SPEED
AINP
16
15
14
4
MSP430x4xx
or Other
Microprocessor
AINN
9
VREFN
12
SW
GND
GND
2, 3, 11
(1) Place a 0.1μF or higher capacitor as close as possible on both AVDD and DVDD.
(2) Place capacitor very close to the ADS1131 CAP pins for optimal performance.
Figure 10. Weigh Scale Example
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Copyright © 2009–2013, Texas Instruments Incorporated
Product Folder Links: ADS1131
13
ADS1131
SBAS449C – JULY 2009 – REVISED OCTOBER 2013
www.ti.com
REVISION HISTORY
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision B (September 2011) to Revision C
Page
•
Changed pin 12 name from PSW to SW in pinout drawing ................................................................................................. 5
•
Changed pin 12 name from PSW to SW in Pin Descriptions table ...................................................................................... 5
•
Changed pin numbers in Figure 10 to match the device pinout ......................................................................................... 13
Changes from Revision A (May 2010) to Revision B
Page
•
Changed Supply Range Features bullet ............................................................................................................................... 1
•
Deleted ESD Ratings row and footnote 2 from Absolute Maximum Ratings table ............................................................... 2
•
Changed Digital Input/Output, VIH Logic level parameter minimum specification in Electrical Characteristics table ........... 3
•
Changed Power Supply, Power-supply voltage parameter minimum specification in Electrical Characteristics table ........ 4
•
Deleted Power Supply, Analog supply current parameter maximum specifications in Electrical Characteristics table ....... 4
•
Deleted Power Supply, Digital supply current parameter maximum specifications in Electrical Characteristics table ........ 4
•
Deleted Power Supply, Power dissipation parameter maximum specifications in Electrical Characteristics table .............. 4
•
Deleted minimum specification and added typical specification to tUPDATE row of table corresponding to Figure 6 ........... 10
•
Deleted Power-Up Sequence section ................................................................................................................................. 12
14
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Copyright © 2009–2013, Texas Instruments Incorporated
Product Folder Links: ADS1131
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
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)
(4/5)
(6)
ADS1131ID
ACTIVE
SOIC
D
16
40
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 85
ADS1131
ADS1131IDR
ACTIVE
SOIC
D
16
2500
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 85
ADS1131
(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