SBAS941A May   2019  – November 2019 AMC1035-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Application Example
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1      Absolute Maximum Ratings
    2. 6.2      ESD Ratings Automotive
    3. Table 1. Recommended Operating Conditions
    4. 6.3      Thermal Information
    5. 6.4      Electrical Characteristics
    6. 6.5      Switching Characteristics
    7. 6.6      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 Analog Input
      2. 7.3.2 Modulator
      3. 7.3.3 Reference Output
      4. 7.3.4 Clock Input
      5. 7.3.5 Digital Output
      6. 7.3.6 Manchester Coding Feature
    4. 7.4 Device Functional Modes
      1. 7.4.1 Output Behavior in Case of a Full-Scale Input
      2. 7.4.2 Fail-Safe Output
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Digital Filter Usage
    2. 8.2 Typical Applications
      1. 8.2.1 Voltage Sensing
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 IGBT Temperature Sensing
      3. 8.2.3 What to Do and What Not to Do
  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 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.3.1 Analog Input

The AMC1035-Q1 incorporates front-end circuitry that contains a buffered sampling stage, followed by a ΔΣ modulator. To support a bipolar input range, the device uses a charge pump that allows single-supply operation to simplify the overall system design and minimize the circuit cost. For reduced offset and offset drift, the input buffer is chopper-stabilized with the switching frequency set at fCLKIN / 32. Figure 37 shows the spur created by the switching frequency.

AMC1035-Q1 D036_SBAS837.gif
sinc3 filter, OSR = 2, fCLKIN = 20 MHz, fIN = 1 kHz
Figure 37. Quantization Noise Shaping

The linearity and noise performance of the device are ensured only when the differential analog input voltage remains within the specified linear full-scale range (FSR), that is ±1 V, and within the specified input common-mode range.

Figure 38 shows the specified common-mode input voltage that applies for the full-scale input voltage range as specified in this document along with the corresponding common-mode undervoltage and overvoltage threshold levels.

If smaller input signals are used, the operational common-mode input voltage range widens. Figure 39 shows the common-mode input voltage that applies with no differential input signal; that is, when the voltage applied on AINP is equal to the voltage applied on AINN. The common-mode input voltage range scales with the actual differential input voltage between this range and the range in Figure 38.

AMC1035-Q1 ai_Vcm_FS_bas837.gif
Figure 38. Common-Mode Input Voltage Range With a
Full-Scale Differential Input Signal of ±1.25 V
AMC1035-Q1 ai_Vcm_no_input_bas837.gif
Figure 39. Common-Mode Input Voltage Range With a
Zero Differential Input Signal