SBAU171D May   2010  – January 2016 ADS1198 , ADS1298

 

  1.   ADS1298ECG-FE/ADS1198ECG-FE
    1.     Trademarks
    2. 1 ADS1298ECG-FE/ADS1198ECG-FE Overview
      1. 1.1 Important Disclaimer Information
      2. 1.2 Introduction
      3. 1.3 Supported Features
      4. 1.4 Features Not Supported in Current Version
      5. 1.5 ADS1x98ECG-FE Hardware
      6. 1.6 Minimum System Requirements for ADS1x98ECG-FE Evaluation Software
    3. 2 Quick Start
      1. 2.1 Default Jumper/Switch Configuration
      2. 2.2 ADS1x98ECG-FE Operation
    4. 3 Using the ADS1298ECG-FE Software
      1. 3.1 Application User Menu
      2. 3.2 Top-Level Application Controls
      3. 3.3 About Tab
      4. 3.4 ADC Register Tab
        1. 3.4.1 Standby and Reset Controls
        2. 3.4.2 Channel Registers Tab (ADC Register)
          1. 3.4.2.1 Global Channel Registers
          2. 3.4.2.2 Channel Control Registers
        3. 3.4.3 LOFF and RLD Tab (ADC Register)
          1. 3.4.3.1 Lead-Off Detection and Current Direction Control Registers
          2. 3.4.3.2 Right Leg Drive Derivation Control Registers
        4. 3.4.4 GPIO and OTHER Registers Tab (ADC Register)
          1. 3.4.4.1 Wilson Central and Augmented Lead Registers
        5. 3.4.5 Register Map (ADC Register)
      5. 3.5 Analysis Tab
        1. 3.5.1 Scope Tab (Anaysis)
          1. 3.5.1.1 Zoom Tool
        2. 3.5.2 Histogram Tab (Analysis)
        3. 3.5.3 FFT Tab
        4. 3.5.4 ECG Tab (Analysis)
      6. 3.6 Save Tab
    5. 4 ADS1x98ECG-FE Input Signals
      1. 4.1 Input Short Testing
      2. 4.2 Internal Test Signals Input
      3. 4.3 Temperature Sensor
      4. 4.4 Normal Electrode Input
        1. 4.4.1 Capturing 12-Lead ECG Signals
      5. 4.5 MVDD Input, RLD Measurement, RLD Positive Electrode Driver, and RLD Negative Electrode Driver
      6. 4.6 Lead Derivation
      7. 4.7 Wilson Center Terminal (WCT)
      8. 4.8 Right Leg Drive
        1. 4.8.1 RLD Common Mode Voltage
        2. 4.8.2 Driving the RLD Cable Shield
      9. 4.9 PACE Detection
    6. 5 ADS1298ECG-FE/ADS1198ECG-FE Hardware Details
      1. 5.1 Jumper Description
      2. 5.2 Power Supply
      3. 5.3 Clock
      4. 5.4 Reference
      5. 5.5 Analog Output Signals
      6. 5.6 Digital Signals
      7. 5.7 Analog Input Signals
        1. 5.7.1 Patient Simulator Input
        2. 5.7.2 Arbitrary Input Signals
  2. ASchematics, BOM, Layout, and ECG Cable Details
    1. A.1 Overview
    2. A.2 ADS1x98ECG-FE Front-End Board Schematics
    3. A.3 Bill of Materials
      1. Table 13. Bill of Materials: ADS1x98ECG-FE
    4. A.4 Printed Circuit Board Layout
    5. A.5 ECG Cable Details
  3. BExternal Optional Hardware
    1. B.1 Optional External Hardware (Not Included)
    2. B.2 ADS1x98ECG-FE Power-Supply Recommendations
  4. CSoftware Installation
    1. C.1 Minimum Requirements
    2. C.2 Installing the Software

5.4 Reference

The ADS1298 has an on-chip internal reference circuit that provides reference voltages to the device. Alternatively, the internal reference can be powered down and VREFP can be applied externally. This configuration is achieved with the external reference generators (U3 and U4) and driver buffer. NOTE: U3, U4, and driver buffer are not installed. The externally provided reference voltage can be set to either 4.096V or 2.5V, depending on the analog supply voltage. Measure TP3 to make sure the external reference is correct. The settings for the external reference is described in Table 10.

Table 10. External Reference Jumper Options

Internal Reference External Reference
ADS1298 Reference VREF = 2.5V VREFP = 4.096V VREFP = 2.5V
JP25 Don't Care 2-3 1-2
JP3 Not Installed Installed Installed

The software uses the VREF value from the Reference Voltage control (CONFIG3 register) in Section 3.4.2.1) to calculate the input-referred voltage value for all the tests. The default value is 2.5V. If the user is using an alternative value, the control must be updated to display the collected data to the proper scale.