Texas Instruments LM25117 Wide Vin Synchronous Buck Controller Evaluation Board LM25117EVAL/NOPB LM25117EVAL/NOPB 데이터 시트
제품 코드
LM25117EVAL/NOPB
Powering and Loading Consideration
3.5.3
Overload Protection
The evaluation board is configured with hiccup mode overload protection. The restart time can be
programmed by C20 restart capacitor.
programmed by C20 restart capacitor.
shows hiccup mode operation in the event of an output
short.
Conditions:
Input Voltage = 24VDC
Output Short
Traces:
Top Trace: SW Voltage Volt/div = 10V
Bottom Trace: Inductor Current, Amp/div = 5A
Horizontal Resolution = 20ms/div
Input Voltage = 24VDC
Output Short
Traces:
Top Trace: SW Voltage Volt/div = 10V
Bottom Trace: Inductor Current, Amp/div = 5A
Horizontal Resolution = 20ms/div
Figure 4. Short Circuit
3.5.4
External Clock Synchronization
A TP3 (SYNC) test point has been provided on the evaluation board in order to synchronize the internal
oscillator to the external clock.
oscillator to the external clock.
shows the synchronized switching operation.
Conditions:
Input Voltage = 24VDC
Load Current = 9A
Traces:
Top Trace: SYNC pulse, 20% duty cycle, Volt/div = 5V
Middle Trace: SW voltage, Volt/div = 20V
Bottom Trace: Inductor Current, Amp/div = 5A
Horizontal Resolution = 2µs/div
Input Voltage = 24VDC
Load Current = 9A
Traces:
Top Trace: SYNC pulse, 20% duty cycle, Volt/div = 5V
Middle Trace: SW voltage, Volt/div = 20V
Bottom Trace: Inductor Current, Amp/div = 5A
Horizontal Resolution = 2µs/div
Figure 5. Clock Synchronization
4
AN-2112 LM25117 Evaluation Board
SNVA469B – May 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated