Datasheet

Test Procedure

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6 Test Procedure

6.1 Line/Load Regulation and Efficiency Measurement Procedure

1. Set up EVM as described in Section 4 and Figure 3.

2. Ensure Load is set to constant resistance mode and to sink 0Adc

3. Ensure all jumpers configuration settings per section 5.

4. Ensure the jumper provided in the EVM shorts on J6 before Vin is applied.

5. Increase Vin from 0V to 12V. Using V1 to measure input voltage.

6. Remove the jumper on J6 to enable the controller.

7. Use V2 to measure Vout voltage.

8. Vary Load from 0-14Adc, Vout should be remain in load regulation.

9. Vary Vin from 8V to 20V, Vout should remain in line regulation.

10. Put the jumper on J6 to disable the controller.

11. Decrease Load to 0A

12. Decrease Vin to 0V.

6.2 Control Loop Gain and Phase Measurement Procedure

TPS53319EVM-136 contains a 10Ω series resistor in the feedback loop for loop response analysis.

1. Set up EVM as described in Section 4 and Figure 3.

2. Connect isolation transformer to test points marked TP6 and TP7.

3. Connect input signal amplitude measurement probe (channel A) to TP6. Connect output signal

amplitude measurement probe (channel B) to TP7.

4. Connect ground lead of channel A and channel B to TP9.

5. Inject around 20mV or less signal through the isolation transformer.

6. Sweep the frequency from 100Hz to 1MHz with 10Hz or lower post filter. The control loop gain and

phase margin can be measured.

7. Disconnect isolation transformer from bode plot test points before making other measurements (Signal

injection into feedback may interfere with accuracy of other measurements).

6.3 List of Test Points

Table 6. The Functions of Each Test Points

Test Points Name Description

TP1 VIN Controller input

TP2 Vout Output Voltage

TP3 VREG 5V LDO output

TP4 PGOOD Power Good

TP5 EN Enable

TP6 CHA Input A for loop injection

TP7 CHB Input B for loop injection

TP8 LL Switching node

TP9 GND Ground

TP10 GND Ground

TP11 GND Ground

TP12 GND Ground

High Efficiency 14A Synchronous Buck Converter with Eco-Mode™ SLVU728–May 2012

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