SPRADE3 January   2024 ADS8329 , LM5180 , LMR38010 , OPA182 , TMS320F28384D , UCC27444 , UCC27524

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Magnet of the MRI
    2. 1.2 Key Challenge to Design a Power Supply to Driver Superconductor
  5. 2Four-Phase Interleaving Phase-Shifted Full Bridge Power Supply Design
  6. 3Sub-System Description
    1. 3.1 Micro-Controller
    2. 3.2 Auxiliary Power Supply
    3. 3.3 Current Sensing
    4. 3.4 ADC Interface
    5. 3.5 MOSFET Driver
  7. 4Summary
  8. 5References

3.2 Auxiliary Power Supply

The LM5180 is a primary-side regulated (PSR) fly-back converter with high efficiency over a wide input voltage range of 4.5V to 65V. The isolated output voltage is sampled from the primary-side fly-back voltage, eliminating the need for an optocoupler, voltage reference, or third winding from the transformer for output voltage regulation. LM5180 integrates many other functions for an isolated power supply such as soft start, Input UVLO and thermal shutdown protection, Hiccup-mode overcurrent fault protection, Internal loop compensation, Soft switching avoids diode reverse recovery and low EMI.

GUID-20231220-SS0I-SHXN-VGM2-PTZDMT1X96RJ-low.svg Figure 3-1 Power Supply for System

LM5180 can be used in this system for power supply TMS320C28384D and associated supporting circuits such as MOSFET driver. The output voltage can be setup by Equation 2. NPS is the turn ratio between primary side and secondary side. VD is the drop voltage of rectifier diode, VOUT is output voltage, RSET is 12.1k and VREF is 1.21V according data sheet.

Equation 2. RFB=Vout+VD×NPS×RSETVREF=Vout+VD×NPS0.1mA