SNVU739A October   2020  – August 2021 LM5157-Q1

 

  1.   Trademarks
  2. 1Features and Electrical Performance
    1. 1.1 Electrical Parameters
    2. 1.2 Configuration Points
  3. 2Application Schematic
  4. 3EVM Picture
  5. 4Test Setup and Procedure
    1. 4.1 Test Setup
    2. 4.2 Test Equipment
  6. 5Test Results
    1. 5.1 Efficiency Curve
    2. 5.2 Load Regulation Curve
    3. 5.3 Thermal Performance
    4. 5.4 Steady State Waveforms
    5. 5.5 Start-Up Waveforms
    6. 5.6 Load Transient Waveforms
    7. 5.7 AC Loop Response Curves
  7. 6Design Files
    1. 6.1 Schematic
    2. 6.2 Bill of Materials
  8. 7Revision History

1.2 Configuration Points

Table 1-2 indicates the available test points and configuration jumpers. These points offer flexibility in configuring the evaluation module and include but not limited to:

  • BIAS pin to be connected to the following:
    • External supply (VAUX)
    • Input voltage (VIN)
    • Regulated output voltage (VOUT)
    • VCC pin
  • PGOOD pin to be supplied by either VCC or VAUX
  • External clock synchronization
  • Shut-down signal by pulling the SD pin high
  • Four different operation modes to enable and disable the spread spectrum and hiccup mode

Table 1-2 Jumper Description
JUMPERPINDESCRIPTION
TP1VIN+Positive input voltage sense connection
TP2SWProbe point for the switch node of the LM5157 boost circuit
TP3VOUT+Positive output voltage sense connection
TP4GNDNegative input voltage sense connection
TP5GNDNegative output voltage sense connection
TP6SYNCInput for external clock signal. To implement the external clock synchronization, remove the jumper resistor R10 and tie the external signal to the TP6 (SYNC).
TP7VAUXSupply the BIAS pin from an external supply (if J9 is connected).
TP8VOUT+Loop response positive injection point (bottom side)
TP9UVLOMiddle point of UVLO resistor divider
TP10VOUT–Loop response negative injection point (bottom side)
TP11SDHigh signal pulls the UVLO pin to ground entering shutdown mode
TP12 AGND Negative input of external signals
J6Pin 1 to pin 2Connect VOUT to the BIAS pin of the LM5157 through D2 (only set one jumper to J6, J7, J8, or J9).
Pin 2 to pin 3Directly connect VOUT to the BIAS pin of the LM5157 (only set one jumper to J6, J7, J8, or J9).
J7Pin 1 to pin 2Connect VIN to the BIAS pin of the LM5157 through D3 (only set one jumper to J6, J7, J8, or J9).
Pin 2 to pin 3Directly connect VIN to BIAS pin of the LM5157 (only set one jumper to J6, J7, J8, or J9).
J8Pin 1 to pin 2Directly connect VCC to the BIAS pin (only set one jumper to J6, J7, J8 or J9).
J9Pin 1 to pin 2Directly connect VAUX to the BIAS pin (only set one jumper to J6, J7, J8, or J9).
J10 SS (Pin 1) Monitor the SS pin.
COMP (Pin 2) Monitor the COMP pin.
AGND (Pin 3) Connection to AGND plane
SYNC (Pin 4) Monitor the EN/UVLO/SYNC pin.
PGOOD (Pin 5) Monitor the PGOOD pin.
BIAS-IC (Pin 6) Monitor the BIAS pin.
VCC (Pin 7) Monitor the VCC pin.
J11 (only use one jumper on J11) Pin 1 to pin 2 (NN) Hiccup mode disabled, spread spectrum disabled
Pin 3 to pin 4 (HS) Hiccup mode enabled, spread spectrum enabled
Pin 5 to pin 6 (HN) Hiccup mode enabled, spread spectrum disabled
Pin 7 to pin 8 (NS) Hiccup mode disabled, spread spectrum enabled