S4059D four-cell lithium battery charging charging IC
Overview
FS4059D is 5V input, supporting battery charging management IC four-cell lithium battery.
The FS4059D has a built-in MOS transistor and adopts an asynchronous switching architecture, which requires very few peripherals during application, which can effectively reduce the overall size of the solution and the cost of the bill of materials. .
The FS4059D's boost switching charge converter operates at 90% efficiency. The input voltage of FS4059D is 5V and it has a built-in adaptive loop that can intelligently adjust the charging current to prevent the adapter output from being pulled. It can match all adapters.
Description
20W, 2A input asynchronous switch boosts charging
Increases charging efficiency by 85%
C currentExternally adjustable load
Automatically adjust input current, matches all adapters
Supports LED charging status indication
Built-in Power MOS
600KHZ switching frequency, can support 2.2uH inductance
Output overvoltage, short circuit protection
Input undervoltage, overvoltage protection
Integrated circuit overheat protection
ESD 4KV
Application
Bluetooth Speaker
Wayie-Talkie
May I ask what is the circuit How can I see? without image? You can understand the principle of a single protection card.
1. Overload protection point and overload protection recovery point voltage
When the battery charging voltage reaches the set value. VC, 4.125-4.300 V (specific voltage of overload protection point, depending onof the chip manufacturer's parameters, the manufacturer's application can select the IC chip according to the specific parameters and requirements of the battery core), as shown in the figure above: When VD1, the Cout pin becomes low , the MOS tube T1 is cut off and charging stops; when the cell voltage drops to VCR3.6-4.2V (the specific recovery voltage of overload protection depends on the IC and cell parameter. The design is integrated during design), cost produces a high level, the MOS tube T1 is turned on and charging continues, and the VCR should have a fixed value lower than VC to avoid frequent jumps.
2. Working principle of over-discharge protection and over-discharge protection recovery
During the battery discharge process, when the cell voltage is discharged and drops to the vset value VD (2.1 -2.45V, overdischarge protection point voltage generally cannot be designed and can only be set by different chip manufacturers). When the output voltage VD2 is low, after a short delay, Dout becomes low, T2 is cut off and the discharge stops. When the battery is put into charge, the internal OR gate is reversed, causing T2 to go to again to prepare for the next discharge.
3. Overcurrent and short circuit protection
When the battery discharges, when the charging circuit current exceeds the set value or is short circuited, the MOS tube T2The voltage of the detection resistor R3 will increase and the level of sense resistor R3 will produce a voltage drop. After reaching the potential value set by the integrated circuit, cout2 will become a low level, the MOS tube T2 will be turned off and the current. is cut. Overcurrent valuecan be obtained by modifying R3 to obtain the desired overcurrent value.
The above is the basic principle of battery protection board management for a single battery. This is very simple since the protection point voltage of different materials is different, as well as the protection point voltage and current of each manufacturer. are also different, so the products on the market There are many lithium battery protection IC chips, various major solutions, including mobile power solutions, etc. As a person engaged in the lithium battery industry, it is more important to understand which materials and battery materials IC Price for which the chip parameters in the market are used, to choose according to the different process requirements, which are based on the accumulation of experience.
This article comes from Shenzhen Maifeng E websiteElectronic Technology