SLIA096 January   2022 DRV5021 , DRV5021-Q1 , DRV5023 , DRV5023-Q1 , DRV5032 , DRV5033 , DRV5033-Q1 , TMAG5123 , TMAG5123-Q1 , TMAG5124 , TMAG5124-Q1 , TMAG5231 , TMAG5328

 

  1.   Trademarks
  2. 1Introduction
  3. 2Design Process
    1. 2.1 Mechanical Implementation
    2. 2.2 Magnetic Implementation
    3. 2.3 Magnet Sensor Placement
    4. 2.4 Prototyping and Bench Testing
    5. 2.5 Layout
    6. 2.6 Bench Testing
    7. 2.7 Bench Results
    8. 2.8 Error Sources
      1. 2.8.1 Offsets
      2. 2.8.2 Roll, Yaw, and Pitch
      3. 2.8.3 Magnet Variation
      4. 2.8.4 Device Variation and Temperature Drift
      5. 2.8.5 External Fields
      6. 2.8.6 Nearby Material Influence
      7. 2.8.7 Bench Setup Error
  4. 3Summary

Device Variation and Temperature Drift

As previously indicated, every type of Hall-effect device, will have some manufacturing variation and its performance will drift with temperature. These issues are captured by the minimum and maximum bounds found in the data sheet as shown in Table 2-2. At a minimum these bounds should be considered in the design and are incorporated into the calculator. Smaller differences between the minimum and maximum for BOP and BRP will lead to much tighter designs with less variation.

Table 2-2 DRV5033 Magnetic Characteristics over operating free-air temperature range (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
DRV5033FA: ±3.5 / ±2 mT
BOP Operate point TA = –40°C to 125°C ±1.8 ±3.5 ±6.8 mT
BRP Release point ±0.5 ±2 ±4.2 mT
Bhys Hysteresis; Bhys = (BOP – BRP) ±1.5 mT
BO Magnetic offset; BO = (BOP + BRP) / 2 ±2.8 mT
DRV5033AJ: ±6.9 / ±3.5 mT
BOP Operate point TA = –40°C to 125°C ±3 ±6.9 ±12 mT
BRP Release point ±1 ±3.5 ±5 mT
Bhys Hysteresis; Bhys = (BOP – BRP) 3.4 mT
BO Magnetic offset; BO = (BOP + BRP) / 2 5.2 mT

Aside from BOP and BRP variation, die placement and more importantly Hall-element placement can have some variation. This variation is typically found in the data sheet in a figure similar to Figure 2-31 and is equivalent to an offset error.

GUID-D8DBD528-DB0A-4515-878D-562E9E7ADCC1-low.gif Figure 2-31 Hall Element Placement Example