background image

MCP16251 One-Cell Boost Converter with External UVLO Circuit

DS50002561A-page 20

 2017 Microchip Technology Inc.

FIGURE 2-5:

Board Hysteresis Profile; X-Axis is V

IN

 and Y-Axis is EN.

The UVLO circuit consumes approximately 0.2 µA before start-up and 1.6-2 µA when 
the Boost Converter is switching. 

Figure 2-6

 shows the UVLO circuit current 

consumption vs. the input voltage.

FIGURE 2-6:

UVLO Circuit Current Consumption vs. Input Voltage.

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0.6

0.7

0.8

0.9

1

1.1

1.2

1.3

V

IN

(V)

UVLO Start 

UVLO Stop 

I

Q

 (µ

A)

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Downloaded from

Arrow.com.

Summary of Contents for MCP1623/4

Page 1: ... 2017 Microchip Technology Inc DS50002561A MCP16251 One Cell Boost Converter with External UVLO Circuit Reference Design Downloaded from Arrow com ...

Page 2: ...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 dsPIC DSCs KEELOQ code hopping devices Serial EEPROMs microperipherals nonvolatile memory and analog products In addition Microchip s quality system...

Page 3: ... External UVLO Circuit Kit Contain 13 Chapter 2 Installation and Operation 2 1 Introduction15 2 1 1 MCP16251 One Cell Boost Converter with External UVLO Circuit Features15 2 1 2 Short Battery Considerations Overview 16 2 2 Getting Started 17 2 2 1 Power Input and Output Connection 17 2 2 2 MCP16251 One Cell Boost Converter with External UVLO Circuit Operation 18 Appendix A Schematic and Layouts A ...

Page 4: ...One Cell Boost Converter with External UVLO Circuit DS50002561A page 4 2017 Microchip Technology Inc NOTES Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com ...

Page 5: ...pment evaluation tool when incorporating wireless and radio telecom functionality is in compliance with the essential requirement and other relevant provisions of the R TTE Directive 1999 5 EC and the FCC rules as stated in the declaration of conformity provided in the module datasheet and the module product page available at www microchip com For information regarding the exclusive limited warran...

Page 6: ...ith External UVLO Circuit DS50002561A page 6 2017 Microchip Technology Inc NOTES Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com ...

Page 7: ...he schematic and layout diagrams for the MCP16251 One Cell Boost Converter with External UVLO Circuit Appendix B Bill Of Materials BOM Lists the parts used to build the MCP16251 One Cell Boost Converter with External UVLO Circuit 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 so...

Page 8: ... 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 options Opa Opa Bit values 0 1 Constants 0xFF A Italic Courier New A variable argument file o w...

Page 9: ...port 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 representatives CUSTOMER SUPPORT Users of Microchip products can receive assistance ...

Page 10: ...icrochip Technology Inc NOTES Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com ...

Page 11: ... quiescent current not switching measured at output a wide input voltage range 0 35 to 5 5V and a low start up voltage 0 82V at a 1 mA load current TABLE 1 1 THE MICROCHIP FAMILY OF BOOST DEVICES Parameter MCP1623 4 MCP16251 2 MCP1640 B C D MCP1642B D Mode PWM Only or PWM PFM PWM PFM PWM Only or PWM PFM PWM Only Start up Voltage 0 65V 0 82V 0 65V 0 65V Input Voltage 0 35V 5 5V 0 35V 5 5V 0 35V 5 5...

Page 12: ...aline cells that consume few milliamperes the MCP16251 device can operate to the minimum input voltage necessary to completely drain the battery In general OEMs recommend that the battery should not be discharged below its specified cut off voltage for an alkaline cell this is 0 8 0 9V Discharging a battery below this point increases the risk of battery leakage and rupture For single cell appli ca...

Page 13: ...0 5 μA from a discharged battery and approximately 2 μA from a fresh battery 1 4 WHAT DOES THE MCP16251 ONE CELL BOOST CONVERTER WITH EXTERNAL UVLO CIRCUIT KIT CONTAIN This MCP16251 One Cell Boost Converter with External UVLO Circuit Kit includes MCP16251 One Cell Boost Converter with External UVLO Circuit ARD00797 Important Information Sheet Downloaded from Arrow com Downloaded from Arrow com Dow...

Page 14: ...com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com ...

Page 15: ... One Cell Boost Converter with External UVLO Circuit has the following features Input Voltage One AA Primary or Rechargeable Battery Output Voltage 3 3V Output Current 125 mA Start up Voltage 1 1V Automatic PFM PWM Operation PWM Switching Frequency 500 kHz Shutdown Voltage 0 8V Q2 2222A Q1 2907A To VIN To EN R1 2 4 M R3 2 2 M R4 3 M R5 1 M R2 2 M Alkaline Downloaded from Arrow com Downloaded from ...

Page 16: ...ting the power that can be supplied to the load The internal resistance also varies with battery chemistry drain rate battery age and temperature Discharging the battery below the OEM recommended cut off voltage will increase the cell s internal resistance For an alkaline cell this is 0 8 0 9V For applications that are battery powered an Undervoltage Lockout UVLO solution is recommended because af...

Page 17: ... Converter with External UVLO Circuit Setup CAUTION Care must be taken when powering the board from an external supply make sure jumper J1 is open if there is also a battery in the AA battery holder Also the minimum input voltage for which the MCP16251 Boost Converter will start switching is 1 1V and the maximum input voltage must not exceed 3 3V VIN VOUT If the input voltage drops below 0 8V the ...

Page 18: ...e If the battery voltage is higher than 1 1V transistor Q1 turns on injecting current in the base of transistor Q2 which also turns on and biases resistor R3 This causes the voltage at the EN pin to go high Because resistor R5 acts as a load for transistor Q1 the collector current of Q1 is small meaning its Collector Emitter Saturation Voltage VCE can be neglected thus VEN VIN and the MCP16251 tur...

Page 19: ...pin when the comparator trips Figure 2 4 The hysteresis ensures a clean High Low transition even in noisy environments and is depicted in Figure 2 5 UVLOSTART VEBQ1 R1 R2 R3 R1 Where UVLOSTART Start up Voltage Threshold VEBQ1 Emitter Base Voltage of Transistor Q1 UVLOSTOP VEBQ1 R1 R2 R3 RCEQ2 R1 VEBQ1 R1 R2 R1 VCESATQ2 Where UVLOSTOP Shutdown Voltage Threshold VEBQ1 Emitter Base Voltage of Transis...

Page 20: ...age 0 0 2 0 4 0 6 0 8 1 1 2 1 4 1 6 1 8 2 0 6 0 7 0 8 0 9 1 1 1 1 2 1 3 VIN V UVLO Start UVLO Stop I Q µA Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Download...

Page 21: ...opper Board Top 3D View Board Bottom 3D View Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from A...

Page 22: ... 3 MMBT2907A Q1 1 2 SW1 1 3 2 MMBT2222A Q2 Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arr...

Page 23: ...ded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from A...

Page 24: ...m Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Download...

Page 25: ...ed from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Ar...

Page 26: ...com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downloaded from Arrow com Downlo...

Page 27: ... Electronics Inc RMCF0805FT2M00 1 R3 Resistor TKF 2 2M 1 1 8W SMD 0805 Yageo Corporation RC0805FR 072M2L 1 R4 Resistor TKF 3M 1 1 8W SMD 0805 Samsung Electro Mechanics America Inc RC2012F305CS 2 R5 R7 Resistor TKF 1M 1 1 8W SMD 0805 Panasonic ECG ERJ 6ENF1004V 1 R6 Resistor TKF 1 69M 1 1 8W SMD 0805 Yageo Corporation RC0805FR 071M69L 1 SW1 Switch DIP 1 SPST 24V 25 mA SMD Wurth Elektronik 418121160...

Page 28: ...52 9310 Japan Tokyo Tel 81 3 6880 3770 Fax 81 3 6880 3771 Korea Daegu Tel 82 53 744 4301 Fax 82 53 744 4302 Korea Seoul Tel 82 2 554 7200 Fax 82 2 558 5932 or 82 2 558 5934 Malaysia Kuala Lumpur Tel 60 3 6201 9857 Fax 60 3 6201 9859 Malaysia Penang Tel 60 4 227 8870 Fax 60 4 227 4068 Philippines Manila Tel 63 2 634 9065 Fax 63 2 634 9069 Singapore Tel 65 6334 8870 Fax 65 6334 8850 Taiwan Hsin Chu ...

Reviews: