How does a card computer like Raspberry Pie realize power supply similar to a mobile phone?

Power management chip

. Advanced applications, such as mobile phone tablet, power management chip is also very advanced, as well as communication with CPU. At this time, the CPU can control and read through commands.

Battery capacity

Waiting for information. if

Think simple.

Point, ordinary lithium battery charging chip can be. Commonly used domestic TP5 100, etc.

Question 12:

On the circuit

Using two diodes, the cathode is connected together to supply power to the following circuit, and the anode is connected with an external power supply and a lithium battery, which is similar.

BAT54C

. When plugging in an external power supply for charging, the voltage must be higher than.

3.7V lithium battery

If the voltage is high, the lithium battery will not supply power to the loop, which is composed of

external power source

Power supply. After the charger is unplugged, the diode connected to the lithium battery is turned on to supply power to the backplane.

Question 3: Lithium battery charging chips are generally available.

Enable end

And a charging state output. The so-called charging status output, that is, the pin connected to the indicator light, can be connected to the CPU input pin for detection without the indicator light, so as to realize charging.

State detection

. As for battery capacity, accurate battery capacity requires a special chip, and the advanced power management chip mentioned above also has this function. If the requirements are not high, use ADC to detect the battery voltage and roughly estimate the power.