SLVUCH5 july   2023 LMQ644A2-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1EVM Description
    1. 1.1 Features and Electrical Performance
  5. 2EVM Performance and Specifications
  6. 3EVM Photo
  7. 4Test Setup and Procedure
    1. 4.1 EVM Connections
    2. 4.2 Test Equipment
    3. 4.3 EVM Setup
      1. 4.3.1 Input Connections
      2. 4.3.2 Output Connections
  8. 5Test Data and Performance Curves
    1. 5.1 Efficiency and Load Regulation Performance
    2. 5.2 Waveforms and Plots
    3. 5.3 EMI Performance
    4. 5.4 Thermal Performance
  9. 6EVM Documentation
    1. 6.1 Schematic
    2. 6.2 Bill of Materials
    3. 6.3 PCB Layout
  10. 7Device and Documentation Support
    1. 7.1 Device Support
      1. 7.1.1 Development Support
        1. 7.1.1.1 Custom Design With WEBENCH® Tools
    2. 7.2 Documentation Support
      1. 7.2.1 Related Documentation

4.1 EVM Connections

Working at an ESD-protected workstation, make sure that any wrist straps, bootstraps, or mats are connected and referencing the user to earth ground before power is applied to the EVM.

GUID-20230518-SS0I-VFWG-VRWL-SJVS3M7QMQH2-low.svg Figure 4-1 EVM Test Setup
Table 4-1 EVM Power Connections
LABELDESCRIPTION
VIN+Positive input power connection
VIN–Negative input power connection
VIN_EMI+ Positive input power connection for EMI test. The minimum operating voltage is 12 V at this input.
VIN_EMI- Negative input power connection for EMI test. The minimum operating voltage is 12 V at this input.
VOUT1+CH1 Positive output power connection
VOUT1–CH1 Negative output power connection
VOUT2+ CH2 Positive output power connection
VOUT2– CH2 Negative output power connection
Table 4-2 EVM Signal Connections
LABEL DESCRIPTION
VINS+ Positive input sense pin for measuring efficiency.
VINS– Negative input sense pin for measuring efficiency.
VOUT1S+ CH1 positive output sense pin for measuring efficiency, and line and load regulation.
VOUT1S– CH1 negative output sense pin for measuring efficiency, and line and load regulation.
VOUT2S+ CH2 positive output sense pin for measuring efficiency, and line and load regulation.
VOUT2S– CH2 negative output sense pin for measuring efficiency, and line and load regulation.
GND Ground reference point
SYNC(+) Positive synchronization pulse input.
SYNC(-) Negative synchronization pulse input.
MODE Light load switching mode selection. Connect pin1 and pin2 for a FPWM mode . Connect pin2 and pin3 for an AUTO mode. Remove any jumper when external synchronization pulse is applied to SYNC.
DITH Spread spectrum enable, disable. Connect pin1 and pin2 to disable the spread spectrum. Remove any jumper to enable the spread spectrum. The EVM needs to restart after changing the jumper setting.
EN1 CH1 enable, disable. Connect pin1 and pin2 to enable CH1. Connect pin2 and pin3 to disable CH1. Remove any jumper when programing the line UVLO using a resistor divider. Populate the external UVLO resistor divider.
EN2 CH2 enable, disable. Connect pin1 and pin2 to enable CH2. Connect pin2 and pin3 to disable CH2. Remove any jumper when programing the line UVLO using a resistor divider. Populate the external UVLO resistor divider.
VSEL1 CH1 output voltage selection. Connect pin1 and pin2 for a fixed 5-V output. Connect pin2 and pin3 for a fixed 3.3-V output. Remove any jumper when programing the regulation target using an external resistor divider. Populate the external feedback resistor divider.
VSEL2 CH2 output voltage selection. Connect pin1 and pin2 for a 5-V output. Connect pin2 and pin3 for a 3.3-V output. Remove any jumper when programing the regulation target using an external resistor divider. Populate the external feedback resistor divider.
PG1 Probe point for CH1 power-good indicator. A pullup resistor is connected to VCC.
PG2 Probe point for CH2 power-good indicator. A pullup resistor is connected to VCC.