SNVU843A April   2023  – November 2023

 

  1.   1
  2.   LM5171 Evaluation Module
  3.   Trademarks
  4. 1Features and Electrical Performance
  5. 2Setup
    1. 2.1 EVM Configurations
    2. 2.2 Bench Setup
    3. 2.3 Test Equipment
    4. 2.4 Jumper Settings for Typical Operation Modes
      1. 2.4.1 Buck Mode with Voltage Regulation
      2. 2.4.2 Boost Mode with Voltage Regulation
      3. 2.4.3 Buck Mode with Current Regulation
      4. 2.4.4 Boost Mode with Current Regulation
      5. 2.4.5 2-EVM Daisy-Chain for 3 or 4-Phase Operation
  6. 3Test Procedure
    1. 3.1 Buck Mode Power-Up and Power-Down Sequence
    2. 3.2 Boost Mode Power-Up and Power-Down Sequence
    3. 3.3 Bidirectional Operation Power-Up and Power-Down Sequence
    4. 3.4 Operating the EVM With External MCU or Other Digital Circuit
  7. 4Test Data
    1. 4.1 Efficiency
    2. 4.2 Step Load Response
    3. 4.3 Dual-Channel Interleaving Operation
    4. 4.4 Typical Start Up and Shutdown
    5. 4.5 DEM and FPWM
    6. 4.6 Mode transition between DEM and FPWM
    7. 4.7 ISET Tracking
    8. 4.8 Pre-charge
    9. 4.9 Protections
  8. 5Design Files
    1. 5.1 Schematics
    2. 5.2 Bill of Materials
    3. 5.3 Board Layout
  9. 6Revision History

3 Test Procedure

Please read the LM5171 data sheet (SNVSCM3) and this user guide before using the EVM. A typical EVM test bench setup is shown in Figure 2-8. The power supplies and loads need to be capable of handling the input and output voltage and current rating of the board.

By default, onboard 10-V bias supply is used. External 10-V bias supply can also be applied following the jumper settings described in Table 2-2

Four external control signals can be used to operate the EVM, which are UVLO, DIR, EN1/2, and ISETA or ISETD (refer to Figure 2-3).

  • UVLO: The main enable command. Apply a voltage > 2.5 V and < 6 V between J17-pins 5 and 6 to enable the EVM. Pulling the voltage at J17-pin 5 low keeps the EVM in shutdown mode.
  • DIR: the current direction command. Apply a voltage > 2 V at J17-pin 9 or J18-pin 9 to operate the EVM in Buck Mode. Apply a voltage < 1 V at the same pin to operate the EVM in Boost Mode. DIR command can also be programmed using J28. Note that DIR must be either active high or low to operate the EVM. If the DIR signal is floating, the EVM can not run.
  • EN1/2: The channel switching enable commands. Apply a voltage > 2 V at J17-pin 7 turns on CH-1 converter, and at J17-pin 21 can turn on CH-2 converter. Removing the voltage at the EN1 and EN2 pins to disable each channel. The channel enable can also be controlled by J29, J30 and J24.
  • ISETA or ISETD: The channel current regulation setting. Applying an analog voltage across J17-pins 11 and 12, or J18-pins 11 and 12, or a PWM signal across J17-pins 13 and 14, or J18-pins 13 and 14, to the EVM regulates the channel DC current, which is also the power inductor dc current, to a level proportional the ISETA voltage or ISETD PWM duty ratio. ISETA is set by the onboard outer voltage loop when closed. Note that, ISETA has 1 V offset, and ISETA=2.2 V commands the EVM to produce 60 A into or out of the 12VDC-port, depending on the operation mode.