SNVU738 March   2022 LM5157 , LM5157-Q1 , LM51571-Q1

 

  1.   Trademarks
  2. 1Features and Electrical Performance
    1. 1.1 Electrical Parameters
    2. 1.2 EVM Power Derating Curve
    3. 1.3 Terminals and Signal Test Points
  3. 2Application Schematic
  4. 3EVM Picture
  5. 4Test Setup and Procedure
    1. 4.1 Bench Setup
    2. 4.2 Test Equipment
    3. 4.3 Precautions
  6. 5Test Data
    1. 5.1 Efficiency
    2. 5.2 Output Regulation
    3. 5.3 Thermal Performance
    4. 5.4 Typical Power Up
    5. 5.5 Output Ripple Voltage
    6. 5.6 Step Load Response
    7. 5.7 Bode Plots
  7. 6Schematics
  8. 7Bill of Materials
  9. 8Board Layout

1.3 Terminals and Signal Test Points

Table 1-2 summarizes the EVM terminals and signal test points.

Table 1-2 EVM Terminals and Signal Test Points
Terminal SIGNAL PINS FUNCTION DESCRIPTION
J1 VIN+ Input Connector
J2 VOUT+ Output Connector
J3 GND Input Return Connector
J4 PGND PGND Signal
J5 GND Output Return Connector
J6 VOUT Pin 1 to 2 Connect VOUT to BIAS pin of the LM5157 through D2
Pin 2 to 3 Directly connect VOUT to BIAS pin of the LM5157
J7 VIN Pin 1 to 2 Connect VIN to BIAS pin of the LM5157 through D3
Pin 2 to 3 Directly connect VIN to BIAS pin of the LM5157
J8 VCC Pin 1 to 2 Directly connect VCC to BIAS pin of the LM5157
J9 VAUX Pin 1 to 2 Connect VAUX to BIAS
J10 MODE Pin 1 to 2 MODE pin connected to AGND. Hiccup mode protection is disabled and spread spectrum is disabled
Pin 3 to 4 MODE pin connected to AGND with 34.4 kOhm. Hiccup mode protection is enabled and spread spectrum is enabled
Pin 5 to 6 MODE pin connected to AGND with 62.0 kOhm. Hiccup mode protection is enabled and spread spectrum is disabled

Pin 7 to 8

 MODE pin connected to AGND with 100 kOhm. Hiccup mode protection is disabled and spread spectrum is enabled
J11 SS Pin 1 IC SS Pin Signal
COMP Pin 2 IC COMP Pin Signal
AGND Pin 3 IC AGND Pin Signal
UVLO Pin 4 IC UVLO Pin Signal and External Enable Control
PGOOD Pin 5 IC PGOOD Pin Signal
BIAS-IC Pin 6 IC BIAS Pin Signal
VCC Pin 7 IC VCC Pin Signal
TP1 VIN+ Input Voltage Sense Point
TP2 VOUT+ Output Voltage Sense Point
TP3 PGND Input Return Sense Point
TP4 PGND Output Return Sense Point
TP5 VOUT+ Positive terminal for AC injection
TP6 SW Switch node
TP7 VOUT- Negative terminal for AC injection

TP8

VAUX

Auxiliary winding
TP9 GND Ground signal for AUX voltage