Texas Instruments TPS40195, User Manual

Page: 10 / 23

6.4 Disable (TP11) and Power Good (TP9)
The TPS40195EVM defaults to the Enabled state.
1. Set up the EVM as described in Section 5.2 and Figure 5-1 .
2. Using a four-channel oscilloscope monitor TP11, TP9, and TP5.
3. Increase V
IN
to 8 V.
4. Set LOAD1 to 10 A.
5. Short TP11 to TP2. Output should drop to zero.
6. Remove short. Output should return to regulation.
7. Repeat steps 4 and 5 above for various V
IN
and LOAD1 combinations.
8. See Section 6.6 for equipment shutdown.
See Section 7.6 for typical disable and power good performance.
6.5 Switch Node (TP4) and SYNC (TP12)
1. Set up the EVM as described in Section 5.2 and Figure 5-1 .
2. Use the oscilloscope to monitor TP4. Set the oscilloscope to the following:
• 1-MΩ input impedance
• 20-MHz Bandwidth
• AC coupling
• 1-μs/div horizontal resolution
• 5-V/div vertical resolution
3. Increase V
IN
to 12 V.
4. Set LOAD1 to 10 A.
5. Vary LOAD1 and observe the oscilloscope.
6. Vary V
IN
and observe the oscilloscope.
7. Set the signal generator to 360 kHz and pulse shape per Figure 6-1 .
8. Connect the signal generator to TP12.
9. Monitor TP12 and TP4 with the oscilloscope.
10. Vary signal generator frequency from 360 kHz to 400 kHz.
11. See
Section 6.6 for equipment shutdown.
2.5V < V
INH
< 6.0V
V
INL
< 0.5V
T < 1/(1.2 x F
SW
)
T
F
< 100ns
Time
Volts
Figure 6-3. Typical TPS40195EVM SYNC Signal. The TPS40195 Synchronizes on the Falling Edge.
6.6 Equipment Shutdown
1. Shut down the oscilloscope.
2. Shut down LOAD1.
3. Shut down V
IN
.
4. Shut down the fan.
Test Procedure www.ti.com
10 TPS40195 Buck Controller Evaluation Module User's Guide SLUU297B – DECEMBER 2007 – REVISED JANUARY 2022
Submit Document Feedback
Copyright © 2022 Texas Instruments Incorporated