SNAS648C
October 2014 – February 2023
TDC1000
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information (1)
6.5
Electrical Characteristics
6.6
Timing Requirements
6.7
Switching Characteristics
6.8
Typical Characteristics
7
Parameter Measurement Information
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Transmitter Signal Path
8.3.2
Receiver Signal Path
8.3.3
Low Noise Amplifier (LNA)
8.3.4
Programmable Gain Amplifier (PGA)
8.3.5
Receiver Filters
8.3.6
Comparators for STOP Pulse Generation
8.3.6.1
Threshold Detector and DAC
8.3.6.2
Zero-Cross Detect Comparator
8.3.6.3
Event Manager
8.3.7
Common-Mode Buffer (VCOM)
8.3.8
Temperature Sensor
8.3.8.1
Temperature Measurement With Multiple RTDs
8.3.8.2
Temperature Measurement With a Single RTD
8.4
Device Functional Modes
8.4.1
Time-of-Flight Measurement Mode
8.4.1.1
Mode 0
8.4.1.2
Mode 1
8.4.1.3
Mode 2
8.4.2
State Machine
8.4.3
TRANSMIT Operation
8.4.3.1
Transmission Pulse Count
8.4.3.2
TX 180° Pulse Shift
8.4.3.3
Transmitter Damping
8.4.4
RECEIVE Operation
8.4.4.1
Single Echo Receive Mode
8.4.4.2
Multiple Echo Receive Mode
8.4.5
Timing
8.4.5.1
Timing Control and Frequency Scaling (CLKIN)
8.4.5.2
TX/RX Measurement Sequencing and Timing
8.4.6
Time-of-Flight (TOF) Control
8.4.6.1
Short TOF Measurement
8.4.6.2
Standard TOF Measurement
8.4.6.3
Standard TOF Measurement With Power Blanking
8.4.6.4
Common-Mode Reference Settling Time
8.4.6.5
TOF Measurement Interval
8.4.7
Averaging and Channel Selection
8.4.8
Error Reporting
8.5
Programming
8.5.1
Serial Peripheral Interface (SPI)
8.5.1.1
Chip Select Bar (CSB)
8.5.1.2
Serial Clock (SCLK)
8.5.1.3
Serial Data Input (SDI)
8.5.1.4
Serial Data Output (SDO)
8.6
Register Maps
9
Application and Implementation
9.1
Application Information
9.2
Typical Applications
9.2.1
Level and Fluid Identification Measurements
9.2.1.1
Design Requirements
9.2.1.2
Detailed Design Procedure
9.2.1.2.1
Level Measurements
9.2.1.2.2
Fluid Identification
9.2.1.3
Application Curves
9.2.2
Water Flow Metering
9.2.2.1
Design Requirements
9.2.2.2
Detailed Design Procedure
9.2.2.2.1
Regulations and Accuracy
9.2.2.2.2
Transit-Time in Ultrasonic Flow Meters
9.2.2.2.3
ΔTOF Accuracy Requirement Calculation
9.2.2.2.4
Operation
9.2.2.3
Application Curves
9.3
Power Supply Recommendations
9.4
Layout
9.4.1
Layout Guidelines
9.4.2
Layout Example
10
Device and Documentation Support
10.1
Device Support
10.1.1
Development Support
10.2
Receiving Notification of Documentation Updates
10.3
Support Resources
10.4
Trademarks
10.5
Electrostatic Discharge Caution
10.6
Glossary
11
Mechanical, Packaging, and Orderable Information
Package Options
Mechanical Data (Package|Pins)
PW|28
MPDS364
Thermal pad, mechanical data (Package|Pins)
Orderable Information
snas648c_oa
snas648c_pm
1
Features
Measurement range: up to 8 ms
Operating current: 1.8 µA (2 SPS)
Transmitter channels TX1/TX2:
Supports single or dual-transducer application
Programmable excitation: 31.25 kHz to 4 MHz, up to 31 pulses
Receiver channels RX1/RX2:
STOP cycle-to-cycle jitter: 50 ps
RMS
Low-noise and programmable gain amplifiers
Access to signal chain for external filter design
Programmable threshold comparator for echo qualification
Automatic channel swapping for differential Time-of-Flight (TOF) measurement
Programmable low power mode for long TOF measurements
Temperature measurement
Interface to two PT1000/500 RTDs
RTD-to-RTD matching accuracy 0.02°C
RMS
Operating temperature range: –40°C to 125°C