Table of Contents
1.0 General Description ......................................................................................................................... 1
2.0 Features ........................................................................................................................................ 1
3.0 Key Specifications ........................................................................................................................... 1
4.0 Applications .................................................................................................................................... 1
5.0 Typical Application ........................................................................................................................... 1
6.0 Block Diagram ................................................................................................................................ 2
7.0 Ordering Information ........................................................................................................................ 5
8.0 Connection Diagram ........................................................................................................................ 5
9.0 Pin Descriptions .............................................................................................................................. 6
10.0 Absolute Maximum Ratings ............................................................................................................. 7
11.0 Operating Ratings .......................................................................................................................... 7
12.0 Electrical Characteristics ................................................................................................................ 7
13.0 Timing Diagrams ......................................................................................................................... 12
14.0 Specific Definitions ...................................................................................................................... 15
15.0 Typical Performance Characteristics .............................................................................................. 16
16.0 Functional Description .................................................................................................................. 22
16.1 SIGNAL PATH ..................................................................................................................... 22
16.1.1 Reference Input (VREF) .............................................................................................. 22
16.1.2 Flexible Input MUX (VIN) ............................................................................................. 22
16.1.3 Selectable Gains (FGA & PGA) .................................................................................... 23
16.1.4 Buffer (BUFF) ............................................................................................................ 23
16.1.5 Internal/External CLK Selection .................................................................................... 23
16.1.6 Programmable ODRs .................................................................................................. 23
16.1.7 Digital Filter ............................................................................................................... 24
16.1.8 GPIO (D0–D6) ........................................................................................................... 27
16.2 CALIBRATION ..................................................................................................................... 27
16.2.1 Background Calibration ............................................................................................... 27
16.2.2 System Calibration ...................................................................................................... 28
FIGURE 15. Post-calibration Scaling Data-Flow Diagram ................................................... 29
16.3 CHANNELS SCAN MODE ..................................................................................................... 29
16.4 SENSOR INTERFACE .......................................................................................................... 30
16.4.1 IB1 & IB2 - Excitation Currents ..................................................................................... 30
16.4.2 Burnout Currents ........................................................................................................ 30
16.4.3 Sensor Diagnostic Flags .............................................................................................. 30
16.5 SERIAL DIGITAL INTERFACE ............................................................................................... 32
16.5.1 Register Address (ADDR) ............................................................................................ 32
16.5.2 Register Read/Write Protocol ....................................................................................... 32
16.5.3 Streaming .................................................................................................................. 32
16.5.4 CSB - Chip Select Bar ................................................................................................. 33
16.5.5 SPI Reset .................................................................................................................. 33
16.5.6 DRDYB - Data Ready Bar ............................................................................................ 33
16.5.7 Data Only Read Transaction ........................................................................................ 36
16.5.8 Cyclic Redundancy Check (CRC) ................................................................................. 37
16.6 POWER MANAGEMENT ...................................................................................................... 38
16.7 RESET and RESTART .......................................................................................................... 38
17.0 Applications Information ............................................................................................................... 39
17.1 QUICK START ..................................................................................................................... 39
17.2 CONNECTING THE SUPPLIES ............................................................................................. 39
17.2.1 VA and VIO ............................................................................................................... 39
17.2.2 VREF ........................................................................................................................ 39
17.3 ADC_DOUT CALCULATION .................................................................................................. 39
17.4 REGISTER READ/WRITE EXAMPLES ................................................................................... 40
17.4.1 Writing to Register Examples ....................................................................................... 40
17.4.2 Reading from Register Example ................................................................................... 41
17.5 STREAMING EXAMPLES ..................................................................................................... 42
17.5.1 Normal Streaming Example ......................................................................................... 42
17.5.2 Controlled Streaming Example ..................................................................................... 43
17.6 EXAMPLE APPLICATIONS ................................................................................................... 45
17.6.1 3–Wire RTD ............................................................................................................... 45
17.6.2 Thermocouple and IC Analog Temperature .................................................................... 47
18.0 Registers .................................................................................................................................... 48
18.1 REGISTER MAP .................................................................................................................. 48
18.2 POWER AND RESET REGISTERS ........................................................................................ 49
18.3 ADC REGISTERS ................................................................................................................ 51
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LMP90100/LMP90099/LMP90098/LMP90097
