SLVAFY5 May   2025 TPS1685 , TPS1689 , TPS25984 , TPS25985

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Challenges for Stackable and Parallel Operation of eFuse
  6. 3Techniques for Current Distribution in eFuse
    1. 3.1 Parallel Operation with Individual eFuse Over Current Limit
    2. 3.2 Parallel Operation with Total System Over Current Limit
    3. 3.3 Parallel Operation with Active Current Sharing (ACS)
  7. 4Summary
  8. 5References

3 Techniques for Current Distribution in eFuse

In this section, different current distribution techniques are described with a system example to evaluate the system performance, long term reliability and effective current distribution.

Table 3-1 shows a system example of 58V voltage rail application with four TPS1685 eFuses connected in parallel to support 80A load current. Different path impedance is introduced in each eFuse path to create a realistic mismatch in RDS(on) and path impedance because of mismatch in trace length.

Table 3-1 Design Parameter
Design ParameterExample Value
Input voltage range (VIN)58V
Maximum DC load current (IOUT (max))80A
Number of eFuse in parallel4
Maximum output capacitance (CLOAD)3mF
RDS(on)3.65mΩ
Path impedance_10Ω
Path impedance_20.5mΩ
Path impedance_30.5mΩ
Path impedance_41mΩ
Ambient temperature25°C