Because as circuit increase voltage as the usb 5v to 12v dc dc step up converter.
Usb step up 5v to 12v.
1 basic of dc boost converter.
Step up dc dc converter is based on lm2577 adj ic this project provides 12v output using 5v input maximum output load 800ma.
In vah mode it can be used as multi function multimeter to measure voltage current power battery capacity discharging time temperature.
2 how dc to dc boost converter works.
This circuit is called a boost converter circuit.
Get it as soon as wed may 6.
Includes 7 standard dc tips to suit your device.
In per mode it can be used as a power supply module with 3 5v 12v to 1 0v 24v wide adjutable voltage range.
3 testing and application.
Useful for powering all sorts of 12v devices direct from a computer or other usb charging source.
The usb to 9v cable can be used to power the router via power bank if power down.
12v 1a rated output.
The primary circuit is shown in figure 1.
Note your usb port must be equipped for high current charging 2 1a or greater.
4 1 out of 5 stars 186.
The lm2577 are monolithic integrated circuits that provide all of the power and control functions for step up boost fly back and forward converter switching regulators.
Usb to 9v 5v to 12v step up drok usb cable 5v boost to 9v 12v voltage converter 1a step up volt transformer dc power regulator line with led display.
This usb step up down module support two mode.
Usb to 9v 5v to 12v step up drok usb cable 5v boost to 9v 12v voltage converter 1a step up volt transformer dc power regulator line with led display 4 2 out of 5 stars 274 10 98.
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