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Features
- Programmable charging current up to 500mA
- No need for external MOSFET, sensing resistor, reverse diode
- Constant current or constant voltage mode operation, with thermal protection function Preset charging voltage
- Standby current is 20uA
- 2.9V slow charge voltage
- Soft start limits the inrush current
- Adopt SOT23-5 package, application line
Product application
- Microphone Battery
- Light Camera
- Mobile Phones, PDAs, MP3 players
- Bluetooth headsets
External programming of the load current:
General Formula:
- I_bat = 1000/ R_prog
- R_prog = 1000 / I_bat
- R_prog = 1000 / 300
- R_Prog = 3.3K
- I_bat = 1000/ R_prog
- R_prog = 1000 / I_bat
- R_prog = 1000 / 500
- R_Prog = 2K
Model | R_prog | I_bat |
1 | 10K | 100mA |
2 | 5K | 200mA |
3 | 3,3K | 300mA |
4 | 2,5K | 400mA |
5 |
2K |
500mA
|
The Circuit Schematic
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Fig. 3 - Automatic Programmable 4.2V Battery Charge, Current up to 500mA using TH7R IC |
Printed Circuit Board
In Figure 3, we provide the PCB - Printed Circuit Board, in GERBER, PDF and PNG files. These files are available for free download, on the MEGA server, in a direct link, without any bypass.All to make it easier for you to do a more optimized assembly, either at home, or with a company that prints the board. You can download the files in the Download option below.
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Fig. 4 - PCB Automatic Programmable 4.2V Battery Charge, Current up to 500mA using TH7R IC |