background image

MIC2128 Evaluation Board User’s Guide

DS50002533A-page 6

 2016 Microchip Technology Inc.

NOTES:

Содержание MIC2128

Страница 1: ... 2016 Microchip Technology Inc DS50002533A MIC2128 Evaluation Board User s Guide ...

Страница 2: ...orized access to your software or other copyrighted work you may have a right to sue for relief under that Act Microchip received ISO TS 16949 2009 certification for its worldwide headquarters design and wafer fabrication facilities in Chandler and Tempe Arizona Gresham Oregon and design centers in California and India The Company s quality system processes and procedures are for its PIC MCUs and ...

Страница 3: ... 2016 Microchip Technology Inc DS50002533A page 3 Object of Declaration MIC2128 Evaluation Board ...

Страница 4: ...DS50002533A page 4 2016 Microchip Technology Inc NOTES ...

Страница 5: ...n Board Kit Contains 12 Chapter 2 Installation and Operation 2 1 System and Configuration Requirements 13 2 2 Board Setup 13 2 3 Circuit Description 14 2 3 1 Feedback Resistors 14 2 3 2 SW Node 14 2 3 3 Current Limit 14 2 3 4 Loop Gain Measurement 16 2 3 5 Setting the Switching Frequency 16 2 3 6 Setting the Soft Start Time 17 2 3 7 Auxiliary Bootstrap LDO EXTVDD 18 Appendix A Schematic and Layout...

Страница 6: ...MIC2128 Evaluation Board User s Guide DS50002533A page 6 2016 Microchip Technology Inc NOTES ...

Страница 7: ...d Appendix A Schematic and Layouts Shows the schematic and layout diagrams for the MIC2128 Evaluation Board Appendix B Bill of Materials BOM Lists the parts used to build the MIC2128 Evaluation Board NOTICE TO CUSTOMERS All documentation becomes dated and this manual is no exception Microchip tools and documentation are constantly evolving to meet customer needs so some actual dialogs and or tool ...

Страница 8: ...ld characters A dialog button Click OK A tab Click the Power tab N Rnnnn A number in verilog format where N is the total number of digits R is the radix and n is a digit 4 b0010 2 hF1 Text in angle brackets A key on the keyboard Press Enter F1 Courier New font Plain Courier New Sample source code define START Filenames autoexec bat File paths c mcc18 h Keywords _asm _endasm static Command line opt...

Страница 9: ...ts latest software releases and archived software General Technical Support Frequently Asked Questions FAQs technical support requests online discussion groups Microchip consultant program member listing Business of Microchip Product selector and ordering guides latest Microchip press releases listing of seminars and events listings of Microchip sales offices distributors and factory representativ...

Страница 10: ...MIC2128 Evaluation Board User s Guide DS50002533A page 10 2016 Microchip Technology Inc NOTES ...

Страница 11: ...ures What the MIC2128 Evaluation Board Kit Contains 1 2 MIC2128 EVALUATION BOARD OVERVIEW The MIC2128 Evaluation Board is a constant frequency synchronous buck controller featuring a unique adaptive on time control architecture The MIC2128 operates over an input supply range of 4 5V to 75V The output voltage is adjustable down to 0 6V with a guaranteed accuracy of 1 The device operates with progra...

Страница 12: ...ut of the converter A logic level enable EN signal can be used to enable or disable the controller Can start up monotonically into a pre biased output Features an open drain power good signal PG which signals when the output is in regulation Operates in discontinuous conduction mode during soft start at light loads The basic parameters of the evaluation board are Input 7V to 75V Optimized for 48V ...

Страница 13: ...ter and input voltage at VVIN and GND terminals with voltmeter Do not apply power until Step 4 2 Connect a load to the VOUT and GND terminals The load can be either a passive resistive or an active electronic type A current meter may be placed between the VOUT terminal and load to monitor the output current Ensure the output voltage is monitored at the VOUT terminal 3 Enable Input An EN connector ...

Страница 14: ... Current Limit The MIC2128 Evaluation Board uses the low side MOSFET RDS ON to sense inductor current In each switching cycle of the MIC2128 converter the inductor current is sensed by monitoring the voltage across the low side MOSFET during the OFF period of the switching cycle during which low side MOSFET is ON An internal current source of 96 µA generates a voltage across the external current l...

Страница 15: ... start successfully The MOSFET RDS ON varies 30 to 40 with temperature Therefore it is recommended to add a 30 margin to ICL in the above equation to avoid false current limiting due to increased MOSFET junction temperature rise It is also recommended to connect the SW pin directly to the drain of the low side MOSFET to accurately sense the MOSFET s RDS ON where ICLIM Desired current limit PP Indu...

Страница 16: ...cy can be adjusted between 270 kHz and 800 kHz by changing the resistor divider network consisting of R2 and R3 The following formula provides the estimated switching frequency EQUATION 2 4 EQUATION 4 The evaluation board design is optimized for a switching frequency of 300 kHz If the switching frequency is programmed to either lower end or higher end the design needs optimization The switching fr...

Страница 17: ... as shown in Figure 2 3 FIGURE 2 3 Setting the Soft Start Time The value of the capacitor can be calculated using the following equation EQUATION 2 5 EQUATION 5 where C19 Capacitor from SS pin to AGND ISS Internal soft start current 1 3 µA typical tSS Output soft start time VREF Reference voltage 0 6V MIC2128 gm 0 6V VREF Comparator COMPENSATION 13 12 CSS ISS 1 3 uA FB SS C19 ISS tSS VREF ...

Страница 18: ...ing the MIC2128 internal circuit bias power from the converter output voltage This LDO is enabled when the voltage on the EXTVDD pin is above 4 6V typical and at the same time the main LDO which operates from VIN is disabled to reduce power consumption If the regulator output voltage is 5V and 12V use output voltage to power the MIC2128 which will increase system efficiency The JU1 jumper can be s...

Страница 19: ...ix A Schematic and Layouts A 1 INTRODUCTION This appendix contains the following schematics and layouts for the MIC2128 Evaluation Board Board Schematic Board Top Silk Layer Board Top Copper layer Board Mid Copper Layer 1 Board Mid Copper Layer 2 Board Bottom Copper layer Board Bottom Silk Layer ...

Страница 20: ...C3 2 2uF C4 C20 C5 330uF C6 C7 C8 C21 47uF OPEN OPEN 0 1uF L1 10uH R14 0ё R10 7 5Kё R9 18Kё R11 1Kё C15 100nF C17 OPEN C16 4 7nF Q1 Q2 Q3 Q4 R2 100Kё R3 60Kё C19 10nF C13 1uF C11 4 7uF R5 10ё R6 0ё R13 0ё R7 1 5kё C12 0 1uF C18 OPEN R1 0ё VDD R8 10Kё C9 0 1uF C10 4 7uF VIN PGND VOUT PGND 1 VVIN VOUT R4 0ё JU1 JU2 JU3 R12 49 9 R15 OPEN C14 OPEN OPEN D2 MIC2128 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16...

Страница 21: ...Schematic and Layouts 2016 Microchip Technology Inc DS50002533A page 21 A 3 BOARD TOP SILK LAYER ...

Страница 22: ...MIC2128 Evaluation Board User s Guide DS50002533A page 22 2016 Microchip Technology Inc A 4 BOARD TOP COPPER LAYER ...

Страница 23: ...Schematic and Layouts 2016 Microchip Technology Inc DS50002533A page 23 A 5 BOARD MID COPPER LAYER 1 ...

Страница 24: ...MIC2128 Evaluation Board User s Guide DS50002533A page 24 2016 Microchip Technology Inc A 6 BOARD MID COPPER LAYER 2 ...

Страница 25: ...Schematic and Layouts 2016 Microchip Technology Inc DS50002533A page 25 A 7 BOARD BOTTOM COPPER LAYER ...

Страница 26: ...MIC2128 Evaluation Board User s Guide DS50002533A page 26 2016 Microchip Technology Inc A 8 BOARD BOTTOM SILK LAYER ...

Страница 27: ...ics GRM188R71C472KA 0 C17 0603 size MLCC capacitor DO NOT POPULATE 0 C18 0603 size MLCC capacitor DO NOT POPULATE 1 C19 10 nF X7R 6 3V 1 0 Murata Electronics GRM188R70J103K 1 PCB MIC2128 Evaluation Board Microchip Technology Inc 02 10568 5 R1 R4 R6 R13 R14 0 0603 size resistor Yageo Corporation RC0603FR 070RL 1 R2 100K 0603 size resistor Yageo Corporation RC0603FR 07100KL 1 R3 60K 0603 size resist...

Страница 28: ...le turret through hole noninsulated Keystone Electronics Corp 1593 2 1 L1 10 µH inductor size 13 5 mm X 12 5 mm X 6 2 mm Bourns Inc SRP1265A 100M 2 Q1 Q4 N Channel MOSFET power PAK S08 5 15 mm X 6 15 mm DO NOT POPULATE 2 Q2 Q3 100V 40A N Channel MOSFET power PAK S08 5 15 mm X 6 15 mm Vishay Intertechnology Inc SIR878ADP 4 VIN PGND VOUT PGND Noninsulated banana jack Keystone Electronics Corp 575 4 ...

Страница 29: ...Bill of Materials BOM 2016 Microchip Technology Inc DS50002533A page 29 NOTES ...

Страница 30: ... China Shenyang Tel 86 24 2334 2829 Fax 86 24 2334 2393 China Shenzhen Tel 86 755 8864 2200 Fax 86 755 8203 1760 China Wuhan Tel 86 27 5980 5300 Fax 86 27 5980 5118 China Xian Tel 86 29 8833 7252 Fax 86 29 8833 7256 ASIA PACIFIC China Xiamen Tel 86 592 2388138 Fax 86 592 2388130 China Zhuhai Tel 86 756 3210040 Fax 86 756 3210049 India Bangalore Tel 91 80 3090 4444 Fax 91 80 3090 4123 India New Del...

Страница 31: ...Mouser Electronics Authorized Distributor Click to View Pricing Inventory Delivery Lifecycle Information Microchip ADM00770 ...

Отзывы: