SBAS760C
March 2018 – January 2019
ADS1260
,
ADS1261
PRODUCTION DATA.
1
Features
2
Applications
3
Description
Device Images
Block Diagram
4
Revision History
5
Device Comparison Table
6
Pin Configuration and Functions
Pin Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Timing Requirements
7.7
Switching Characteristics
7.8
Typical Characteristics
8
Parameter Measurement Information
8.1
Noise Performance
9
Detailed Description
9.1
Overview
9.2
Functional Block Diagram
9.3
Feature Description
9.3.1
Analog Inputs
9.3.1.1
ESD Diodes
9.3.1.2
Input Multiplexer
9.3.1.3
Temperature Sensor
9.3.1.4
Power-Supply Readback
9.3.1.5
Inputs Open
9.3.1.6
Internal VCOM Connection
9.3.1.7
Alternate Functions
9.3.2
PGA
9.3.2.1
PGA Bypass Mode
9.3.2.2
PGA Voltage Monitor
9.3.3
Reference Voltage
9.3.3.1
Internal Reference
9.3.3.2
External Reference
9.3.3.3
AVDD - AVSS Reference (Default)
9.3.3.4
Reference Monitor
9.3.4
Level-Shift Voltage (VBIAS)
9.3.5
Burn-Out Current Sources
9.3.6
Sensor-Excitation Current Sources (IDAC1 and IDAC2)
9.3.7
General-Purpose Input/Outputs (GPIOs)
9.3.8
Oversampling
9.3.9
Modulator
9.3.10
Digital Filter
9.3.10.1
Sinc Filter
9.3.10.1.1
Sinc Filter Frequency Response
9.3.10.2
FIR Filter
9.3.10.2.1
FIR Filter Frequency Response
9.3.10.3
Filter Bandwidth
9.3.10.4
50-Hz and 60-Hz Normal Mode Rejection
9.4
Device Functional Modes
9.4.1
Conversion Control
9.4.1.1
Continuous-Conversion Mode
9.4.1.2
Pulse-Conversion Mode
9.4.1.3
Conversion Latency
9.4.1.4
Start-Conversion Delay
9.4.2
Chop Mode
9.4.3
AC-Excitation Mode
9.4.4
ADC Clock Mode
9.4.5
Power-Down Mode
9.4.5.1
Hardware Power-Down
9.4.5.2
Software Power-Down
9.4.6
Reset
9.4.6.1
Power-on Reset
9.4.6.2
Reset by Pin
9.4.6.3
Reset by Command
9.4.7
Calibration
9.4.7.1
Offset and Full-Scale Calibration
9.4.7.1.1
Offset Calibration Registers
9.4.7.1.2
Full-Scale Calibration Registers
9.4.7.2
Offset Self-Calibration (SFOCAL)
9.4.7.3
Offset System-Calibration (SYOCAL)
9.4.7.4
Full-Scale Calibration (GANCAL)
9.4.7.5
Calibration Command Procedure
9.4.7.6
User Calibration Procedure
9.5
Programming
9.5.1
Serial Interface
9.5.1.1
Chip Select (CS)
9.5.1.2
Serial Clock (SCLK)
9.5.1.3
Data Input (DIN)
9.5.1.4
Data Output/Data Ready (DOUT/DRDY)
9.5.1.5
Serial Interface Auto-Reset
9.5.2
Data Ready (DRDY)
9.5.2.1
DRDY in Continuous-Conversion Mode
9.5.2.2
DRDY in Pulse-Conversion Mode
9.5.2.3
Data Ready by Software Polling
9.5.3
Conversion Data
9.5.3.1
Status byte (STATUS)
9.5.3.2
Conversion Data Format
9.5.4
CRC
9.5.5
Commands
9.5.5.1
NOP Command
9.5.5.2
RESET Command
9.5.5.3
START Command
9.5.5.4
STOP Command
9.5.5.5
RDATA Command
9.5.5.6
SYOCAL Command
9.5.5.7
GANCAL Command
9.5.5.8
SFOCAL Command
9.5.5.9
RREG Command
9.5.5.10
WREG Command
9.5.5.11
LOCK Command
9.5.5.12
UNLOCK Command
9.6
Register Map
9.6.1
Device Identification (ID) Register (address = 00h) [reset = xxh]
Table 30.
ID Register Field Descriptions
9.6.2
Device Status (STATUS) Register (address = 01h) [reset = 01h]
Table 31.
STATUS Register Field Descriptions
9.6.3
Mode 0 (MODE0) Register (address = 02h) [reset = 24h]
Table 32.
MODE0 Register Field Descriptions
9.6.4
Mode 1 (MODE1) Register (address = 03h) [reset = 01h]
Table 33.
MODE1 Register Field Descriptions
9.6.5
Mode 2 (MODE2) Register (address = 04h) [reset = 00h]
Table 34.
MODE2 Register Field Descriptions
9.6.6
Mode 3 (MODE3) Register (address = 05h) [reset = 00h]
Table 35.
MODE3 Register Field Descriptions
9.6.7
Reference Configuration (REF) Register (address = 06h) [reset = 05h]
Table 36.
REF Register Field Descriptions
9.6.8
Offset Calibration (OFCALx) Registers (address = 07h, 08h, 09h) [reset = 00h, 00h, 00h]
Table 37.
OFCAL0, OFCAL1, OFCAL2 Registers Field Description
9.6.9
Full-Scale Calibration (FSCALx) Registers (address = 0Ah, 0Bh, 0Ch) [reset = 00h, 00h, 40h]
Table 38.
FSCAL0, FSCAL1, FSCAL2 Registers Field Description
9.6.10
IDAC Multiplexer (IMUX) Register (address = 0Dh) [reset = FFh]
Table 39.
IMUX Register Field Descriptions
9.6.11
IDAC Magnitude (IMAG) Register (address = 0Eh) [reset = 00h]
Table 40.
IMAG Register Field Descriptions
9.6.12
Reserved (RESERVED) Register (address = 0Fh) [reset = 00h]
Table 41.
RESERVED Register Field Descriptions
9.6.13
PGA Configuration (PGA) Register (address = 10h) [reset = 00h]
Table 42.
PGA Register Field Descriptions
9.6.14
Input Multiplexer (INPMUX) Register (address = 11h) [reset = FFh]
Table 43.
INPMUX Register Field Descriptions
9.6.15
Input Bias (INPBIAS) Register (address = 12h) [reset = 00h]
Table 44.
INPBIAS Register Field Descriptions
10
Application and Implementation
10.1
Application Information
10.1.1
Input Range
10.1.2
Input Overload
10.1.3
Burn-out Current Source
10.1.4
Unused Inputs and Outputs
10.1.5
AC-Excitation
10.1.6
Serial Interface and Digital Connections
10.2
Typical Application
10.2.1
Design Requirements
10.2.2
Detailed Design Procedure
10.2.3
Application Curves
10.3
Initialization Setup
11
Power Supply Recommendations
11.1
Power-Supply Decoupling
11.2
Analog Power-Supply Clamp
11.3
Power-Supply Sequencing
12
Layout
12.1
Layout Guidelines
12.2
Layout Example
13
Device and Documentation Support
13.1
Documentation Support
13.1.1
Related Documentation
13.2
Related Links
13.3
Receiving Notification of Documentation Updates
13.4
Community Resources
13.5
Trademarks
13.6
Electrostatic Discharge Caution
13.7
Glossary
14
Mechanical, Packaging, and Orderable Information
1
Features
24-bit, high-precision ADCs
Offset drift: 1 nV/°C
Gain drift: 0.5 ppm/°C
Noise: 30 nV
RMS
(20 SPS, gain = 128)
Linearity: 2 ppm
CMOS PGA gain: 1 to 128
Wide input voltage range: ±7 mV to ±5 V
Data rate: 2.5 SPS to 40 kSPS
2.5-V reference: 2 ppm/°C
Simultaneous 50-Hz and 60-Hz rejection mode
Single-cycle settling mode
Signal and reference monitors
5-V or ±2.5-V power supply
Internal temperature sensor
Cyclic redundancy check (CRC)
Excitation current sources
Sensor burn-out current sources
Four general-purpose inputs/outputs (ADS1261)
AC excitation for bridge sensors (ADS1261)
5-mm × 5-mm VQFN package