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3V to 5V DC Output Step-Up DC-DC Converter using MAX668
The project presented here is a powerful constant-frequency, pulse-width modulating (PWM), current-mode step-up DC-DC switching regulator efficiently producing 5V from input voltages between 3V to 5V. The project can be used in a portable device that works with a battery. The module produces a peak current of up to 1A and an output voltage of 5V DC.
The MAX668 current-mode PWM controllers operate in a wide range of DC-DC conversion applications, including boost, SEPIC, flyback, and isolated output configurations. Optimum conversion efficiency is maintained over a wide range of loads by employing both PWM operation and Maxim’s proprietary Idle Mode control to minimize operating current at light loads. Other features include shutdown, adjustable internal operating frequency or synchronization to an external clock, soft start, adjustable current limit, and a wide (1.8V to 28V) input range.
Features
- Operating Supply 3V to 5V
- Output 5V DC @ 500mA (1Amp Peak)
- Operating Frequency 500Khz
- 4 Pin Header Connector for Input and Output
- PCB dimensions: 32.70 x 21.27 mm
Connections CN1
- Pin 1: 3V to 5V Input
- Pin 2: GND
- Pin 3: GND
- Pin 4: 5V DC Output
Schematic
Parts List
| NO. | QNTY. | REF. | DESC. | MANUFACTURER | SUPPLIER | PART NO |
|---|---|---|---|---|---|---|
| 1 | 1 | CN1 | 4 PIN MALE HEADER PITCH 2.54MM | WURTH | DIGIKEY | |
| 2 | 2 | C1,C5 | 0.1uF/50V SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 3 | 1 | C2 | 100uF/10V | WURTH | DIGIKEY | 732-9197-1-ND |
| 4 | 1 | C3 | 1uF/10V SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 5 | 1 | C4 | 220uF/10V | WURTH | 732-9418-1-ND | |
| 6 | 1 | C6 | 0.22uF/10V SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 7 | 1 | D1 | SS34 | NEXT GEN | DIGIKEY | 3372-SS34TR-ND |
| 8 | 1 | L1 | 4.7uH | EPCOS/TDK | DIGIKEY | 495-1997-2-ND |
| 9 | 1 | R1 | DNP | DO NOT INSTALL | ||
| 10 | 2 | R2,R7 | 0E SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 11 | 1 | R3 | 0.025E 1% SMD SIZE 2512 | MURATA/YAGEO | DIGIKEY | |
| 12 | 1 | R4 | 75K 1% SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 13 | 1 | R5 | 100K 5% SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 14 | 1 | R6 | 24.9K 1% SMD SIZE 0805 | MURATA/YAGEO | DIGIKEY | |
| 15 | 1 | U1 | MAX668 | MAXIM | DIGIKEY | MAX668EUB+-ND |
| 16 | 1 | U2 | FDS6680 SO8 | ON SEMI | RS COMPO. | 671-0605 |
Connections
Gerber View
Photos
Video
MAX668 Datasheet
PCB
