Datasheet

EVM Test Set Up

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5.4 List of Test Points

Table 2. Test Point and Connector Functional Descriptions

TEST POINT NAME DESCRIPTION

Output voltage of EVM; this designator is not populated with a pin in order to facilitate tip and

TP1 Vout+

barrel output ripple voltage measurements in conjunction with TP3, Vout-.

TP2 PGND Primary side power ground. Use this pin as a reference for TP15, VGG.

Output return of EVM; use this pin to facilitate tip and barrel output ripple voltage

TP3 Vout-

measurements in conjunction with TP1, Vout+.

TP4 SW Secondary side switch node, reference the probe to U1_GND, TP11 or TP12.

TP5 VD VD pin, U1. Reference the probe to U1_GND, TP11 or TP12.

Located on the drain trace of the primary side HV MOSFET, the user can cut the trace

TP6 - between this test point and TP8 to insert their own current loop to monitor primary side drain

current.

EN/TOFF pin, U1, shorting this pin to U1_GND (TP11 or TP12) will disable the GATE of U1

TP7 EN

resulting in body diode conduction.

Located on the drain trace of the primary side HV MOSFET, the user can cut the trace

TP8 - between this test point and TP6 to insert their own current loop to monitor primary side drain

current.

TP9 GATE Gate pin, U1. Reference the probe to U1_GND, TP11 or TP12.

TP10 +LOOP Loop injection point, EVM output.

TP11 U1_GND GND pin of U1, use as a return for TP4, TP5, TP7, and TP9.

TP12 U1_GND GND pin of U1, use as a return for TP4, TP5, TP7, and TP9.

TP13 -LOOP Loop injection point

TP14 AUX Auxiliary winding of T1. Reference the probe to TP17, PGND.

TP15 VGG VGG pin, U3. Reference the probe to TP2, PGND.

TP16 ZCD ZCD pin, U3. Reference the probe to TP17, PGND.

TP17 PGND Primary side power ground. Use this pin as a reference for TP14, AUX, and TP16, ZCD.

TP18 - PGND, can be used as a reference when probing the drain pin of Q2

J1 Line Line input from AC source

J2 Vout+ Positive output terminal of the EVM to the load

J3 Neutral Neutral input from the AC Source

J4 Vout- Return connection of the EVM output to the load

5-V, 25-W Flyback Converter With Secondary-Side Synchronous Rectification SLUU434–August 2010