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SNVA445B – August 2010 – Revised April 2013
AN-2066 LM25119 Evaluation Board
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Страница 1: ...ND Be sure to choose the correct connector and wire size when attaching the source power supply and the load 3 2 Source Power The power supply and cabling must present low impedance to the evaluation board Insufficient cabling or a high impedance power supply will droop during power supply application with the evaluation board inrush current If large enough this droop will cause a chattering condi...
Страница 2: ...he MOSFETs to overheat A fan with a minimum of 200LFM should be always provided Figure 1 Typical Evaluation Setup 3 5 Quick Start Up Procedure 1 Set the power supply current limit to at least 20A Connect the power supply to J1 and J2 2 Connect one load with an 8A capacity between J3 and J4 Connect another load with an 8A capacity between J6 and J5 3 Set input voltage to 12V and turn it on 4 Measur...
Страница 3: ...ut voltage during a typical start up with a load of 0 5Ω on the 3 3V output and 0 33Ω on the 1 8V output respectively Conditions Input Voltage 12VDC 0 5Ω Load on 3 3V output 0 33Ω Load on 1 8V output Traces Top Trace 3 3V Output Voltage Volt div 1V Bottom Trace 1 8V Output Voltage Volt div 1V Horizontal Resolution 1 ms div Figure 2 Start up with Resistive Load 3 SNVA445B August 2010 Revised April ...
Страница 4: ...ponse 4 3 Over Load Protection The evaluation board is configured with hiccup mode overload protection The restart time can be programmed by C11 Figure 4 shows hiccup mode operation in the event of an output short on CH1 output One channel may operate in the normal mode while the other is in hiccup mode overload protection Conditions Input Voltage 12VDC Output Short on 3 3V Traces Top Trace SW vol...
Страница 5: ... operates 180 out of phase from the other Conditions Input Voltage 12VDC 8A on 3 3V output 8A on 1 8V output Traces Top Trace SYNC pulse Volt div 5V Middle Trace SW voltage on CH1 Volt div 10V Bottom Trace SW voltage on CH2 Volt div 10V Horizontal Resolution 1 µs div Figure 5 Clock Synchronization 5 SNVA445B August 2010 Revised April 2013 AN 2066 LM25119 Evaluation Board Submit Documentation Feedb...
Страница 6: ...Trace2 VCC Volt div 5V Bottom Trace SS voltage Volt div 5V Horizontal Resolution 20 ms div Figure 6 Shutdown 5 Performance Characteristics Figure 7 shows the efficiency curves The efficiency of the power converter is 90 at 12V with full load current Monitor the current into and out of the evaluation board Monitor the voltage directly at the input and output terminals of the evaluation board Figure...
Страница 7: ...est the interleaved operation Figure 8 Load Connection for Single Output 6 2 External VCC Supply and VCC Disable External VCC supply helps to reduce the temperature and the power loss of the LM25119 at high input voltage By populating D3 and D4 VCC can be supplied from an external power supply Use TP3 as an input of the external VCC supply with 0 1A current limit R36 R35 and C45 should be populate...
Страница 8: ...CH2 For detail information about the loop transfer function measurement see AN 1889 How to Measure the Loop Transfer Function of Power Supplies SNVA364 Figure 9 Loop Response Measurement Setup 8 AN 2066 LM25119 Evaluation Board SNVA445B August 2010 Revised April 2013 Submit Documentation Feedback Copyright 2010 2013 Texas Instruments Incorporated ...
Страница 9: ... Evaluation Board Schematic 7 Evaluation Board Schematic 9 SNVA445B August 2010 Revised April 2013 AN 2066 LM25119 Evaluation Board Submit Documentation Feedback Copyright 2010 2013 Texas Instruments Incorporated ...
Страница 10: ...90JNEA Vishay R2 52 3k 1 0805 MCR10EZHF5232 Rohm R3 15k 1 0603 MCR03EZPFX1502 Rohm R4 22 1k 1 0603 CRCW060322K1FKEA Vishay R5 R16 R21 R22 R35 R NU 36 R37 R6 R7 36 5k 1 0603 CRCW060336K5FKEA Vishay R8 R9 10 ohm 5 0805 CRCW080510R0JNEA Vishay R23 R24 R29 R30 R31 R32 R10 R12 6 98k 1 0805 CRCW08056K98FKEA Vishay R11 2 21k 1 0805 MCR10EZHF2211 Rohm R13 5 49k 1 0805 MCR10EZHF5491 Rohm R14 R15 34k 1 0603...
Страница 11: ...www ti com PCB Layout 8 PCB Layout 11 SNVA445B August 2010 Revised April 2013 AN 2066 LM25119 Evaluation Board Submit Documentation Feedback Copyright 2010 2013 Texas Instruments Incorporated ...
Страница 12: ...PCB Layout www ti com 12 AN 2066 LM25119 Evaluation Board SNVA445B August 2010 Revised April 2013 Submit Documentation Feedback Copyright 2010 2013 Texas Instruments Incorporated ...
Страница 13: ...www ti com PCB Layout 13 SNVA445B August 2010 Revised April 2013 AN 2066 LM25119 Evaluation Board Submit Documentation Feedback Copyright 2010 2013 Texas Instruments Incorporated ...
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