SBAS482C January   2010  – September 2017 ADS7924

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 I2C Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Multiplexer
      2. 7.3.2 ADC Input
      3. 7.3.3 Reference
      4. 7.3.4 Clock
      5. 7.3.5 Data Format
      6. 7.3.6 ADC Conversion Timing
        1. 7.3.6.1 Power-Up Time
        2. 7.3.6.2 Acquisition Time
        3. 7.3.6.3 Conversion Time
        4. 7.3.6.4 Sleep Time
      7. 7.3.7 Interrupt Output (INT)
      8. 7.3.8 PWRCON
      9. 7.3.9 Alarm
    4. 7.4 Device Functional Modes
      1. 7.4.1 ADC Operating Modes
        1. 7.4.1.1 Idle Mode
        2. 7.4.1.2 Awake Mode
        3. 7.4.1.3 Manual-Single Mode
        4. 7.4.1.4 Manual-Scan Mode
        5. 7.4.1.5 Auto-Single Mode
        6. 7.4.1.6 Auto-Scan Mode
        7. 7.4.1.7 Auto-Single With Sleep Mode
        8. 7.4.1.8 Auto-Scan With Sleep Mode
        9. 7.4.1.9 Auto-Burst Scan With Sleep Mode
    5. 7.5 Programming
      1. 7.5.1 I2C Interface
      2. 7.5.2 I2C Address Selection
      3. 7.5.3 I2C Speed Modes
      4. 7.5.4 Slave Mode Operations
        1. 7.5.4.1 Receive Mode
        2. 7.5.4.2 Transmit Mode:
      5. 7.5.5 Writing the Registers
      6. 7.5.6 Reading the Registers
    6. 7.6 Register Map
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Using an Operational Amplifier Between Multiplexer Output and ADC Input
      2. 8.1.2 Using an Operational Amplifier and RC Filter Between Multiplexer Output and ADC Input
      3. 8.1.3 Using an RC Filter Between Multiplexer Output and ADC Input
      4. 8.1.4 Operational Amplifier With Filter and Gain Option Between Multiplexer Output and ADC Input
      5. 8.1.5 Driving an RC Filter With an Operational Amplifier Between Multiplexer Output and ADC Input
      6. 8.1.6 Average Power Consumption
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Setting the Throughput
        2. 8.2.2.2 Selecting the Operational Amplifier
        3. 8.2.2.3 Selecting the RC Filter
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • Intelligent Monitoring:
    • Auto-Sequencing of 4-Channel Multiplexer
    • Individual Alarm Thresholds for Each Channel
    • Programmable Scan Rate
  • MicroPOWER™ Monitoring:
    • Four-Channel Scanning:
      • Every 1 ms → 25 μW
      • Every 10 ms → 5 μW
      • < 1 µA of Power-Down Current
    • Programmable Interrupt Pin Controls Shutdown/Wakeup of the Microcontroller
    • Auto Power-Down Control
    • PWRCON Pin Allows Shutdown of External Operational Amplifiers
  • Wide Supply Range:
    • Analog Supply: 2.2 V to 5.5 V
    • Digital Supply: 1.65 V to 5.5 V
  • Small Footprint: 3-mm × 3-mm WQFN

2 Applications

  • Portable and Battery-Powered Systems:
    • Medical, Communications, Remote Sensor Signal Monitoring, Power-Supply Monitoring
  • Energy Harvesting

3 Description

The ADS7924 is a four-channel, 12-bit, analog-to-digital converter (ADC) with an I2C™ interface. With its low-power ADC core, support for low-supply operation, and a flexible measurement sequencer that essentially eliminates power consumption between conversions, the ADS7924 forms a complete monitoring system for power-critical applications such as battery-powered equipment and energy harvesting systems.

The ADS7924 features dedicated data registers and onboard programmable digital threshold comparators for each input. Alarm conditions can be programmed that generate an interrupt. The combination of data buffering, programmable threshold comparisons, and alarm interrupts minimize the host microcontroller time needed to supervise the ADS7924.

The four-channel input multiplexer (MUX) is routed through external pins to allow a common signal conditioning circuit to be used between the MUX and ADC, thereby reducing overall component count. The low-power ADC uses the analog supply as its reference and can acquire and convert signals in only 10 μs. An onboard oscillator eliminates the need to supply a master clock.

The ADS7924 is offered in a small 3-mm × 3-mm WQFN and is fully specified for operation over the industrial temperature range of –40°C to 85°C.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
ADS7924 WQFN (16) 3.00 mm × 3.00 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

ADS7924 alt_sbas482.gif