CXLB73337 is a complete single lithium ion/lithium polymer battery charging management chip, which adopts the classic three-stage charging algorithm of trickle, constant current and constant voltage (TC-CC-CV) to ensure the safety and full battery. The most prominent highlight is that a single chip integrates the positive and negative reverse connection protection function of the battery terminal and the input power supply (VIN) terminal, which is extremely rare in the industry, it can effectively avoid circuit damage caused by misconnection and greatly improve the reliability and safety of the system.
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[ CXLB73337 ]"
With the increasing popularity of portable electronic devices, the safe and efficient charging of lithium batteries has become a key link in product design. A charge management chip with high integration, comprehensive protection function and simple design can not only improve user experience, but also ensure equipment safety. JTM-IC (jtm-ic.com) launchedCXLB73337, it is such a styleRevolutionary single lithium battery charger chip. It takes itsThe world's first dual reverse connection protection between battery and input power supply,Wide range programmable charging currentAndExtremely high integration, provides a safe, flexible and economical charging solution for all kinds of portable devices.
I. CXLB73337 product core overview
CXLB73337 is a complete single lithium ion/lithium polymer battery charging management chip, using classicTrickle, constant current, constant voltage (TC-CC-CV) three-stage charging algorithmTo ensure that the battery is safe and full. Its most prominent highlight isA single chip integrates the positive and negative reverse connection protection function of the battery terminal and the input power supply (VIN) terminal., which is extremely rare in the industry and can effectively avoid circuit damage caused by misconnection, greatly improving the reliability and safety of the system.
The input voltage range of the chip is3.0V to 8.0V, compatible with USB port (5V) and common AC adapter. Its charging current can be through an external resistor3mA to 600mAFlexible settings in the range can meet various application requirements from micro button batteries to smart phone batteries. Full voltage fixed to high precision2.8V(± 1%). CXLB73337 use ultra-smallSOT23-6 package, the periphery requires only a few components, which is an ideal choice for space-constrained applications.
II. Core advantages and revolutionary features
2.1 Double Reverse connection protection, safe and worry-free:
· Battery reverse connection protection: When the positive and negative poles of the lithium battery are accidentally connected to the BAT pin, the chip immediately enters the shutdown protection state, charging stops, indicating LED slightly light, and the reverse leakage current is less5mA, effectively protect chips and batteries.
· Input power reverse connection protection: When the positive and negative poles of the adapter or USB power supply are connected to the VCC pin in reverse, the chip also enters the protection state, the leakage current is extremely low (<10μa), and the LED goes out. Automatically resume charging after correct connection. These two protection functions fundamentally eliminate risks caused by operational errors and reduce after-sales costs.
2.2. High precision and intelligent charging management:
·Float-charge pressure accuracy of ± 1%To ensure that the battery is accurately filled, avoid overcharging or undercharging, and prolong the battery life.
·C/10 charging termination: When the charging current in the constant voltage stage drops to 1/10 of the set value, the chip automatically stops charging and enters the standby mode. At this time, the battery leakage current is lower1. A, the power consumption is extremely low.
·Automatic recharge: The chip continuously monitors the battery voltage. When the voltage drops to the recharge threshold (about 80%-90% of the full power), a new charging cycle is automatically enabled, keep the battery in a high state.
2.3. Powerful thermal management and power regulation:
·Internal thermal feedback loop: When the chip junction temperature is close135°CAutomatically and linearly reduce the charging current to prevent overheating damage. This allows designers to set the maximum charging current based on typical working conditions rather than extreme conditions and optimize the charging speed.
·Programmable charging current: The current can be accurately set through a single resistor (RPROG). The formula is:RPROG (KΩ) ≈ 1050 / IBAT (mA)(IBAT>100mA). Chips offer a wide range of choices from 3mA to 600mA.
2.4. High integration and concise design:
·Internal integrationPMOS power tube and anti-backfilling circuit, no external isolation diode and current detection resistor are required.
·Complete charging status indication: provides two open-drain output pinsCHRG (charging)AndSTDBY (full/standby), can easily drive LED or connect MCU for status monitoring.
·Internal soft start(About 50μs) effectively suppress surge current generated by plugging and unplugging.
III. Wide range of target application fields
With its compact, secure, and flexible features, CXLB73337 is ideal for the following applications:
·Miniature lithium battery equipment: Bluetooth headset, smart watch, electronic bracelet, smart card, electronic tag, etc.
·Portable consumer electronics: MP3/MP4 player, digital camera, portable game console, e-book, PAD (Tablet PC).
·Communication equipment: battery backup for cellular phones, walkie-talkies, and wireless modules.
·Power supply accessories: miniature charging set, mobile power (as a single battery charging management unit), intelligent charging case.
·IoT devices: all kinds of sensor nodes based on lithium battery power supply, remote control, smart home equipment.
IV. In-depth design guide and practical skills
To help engineers give full play to the performance of CXLB73337, JTM-IC provide the following key design suggestions based on a large number of application cases:
4.1. Charging current setting:
Select the RPROG Resistor based on the required charging current (IBAT). For example:
·500mA charging required: RPROG & asynmp; 1050/500 & asynmp; 2.1 kΩ (measured recommended value).
·100Ma charging required: RPROG & asynmp; 1050/100 & asynmp; 10.5 kΩ (10kΩ available).
·Charge with a low current of 10mA: refer to the data manual table and select RPROG = 100kΩ (about 5mA). Required
Attention: For high-current applications greater than 400mA, chip heating will trigger thermal regulation, and the actual current may be slightly lower than the theoretical value. Good PCB heat dissipation design is crucial.
4.2. Selection and layout of key peripheral components:
4.2.1 input/output capacitors:Strongly recommendedPlace one near each of the VCC and BAT pins.10°fLow-ESR ceramic capacitors (such as X5R/X7R) are used for filtering, energy storage and suppressing voltage spikes, which are crucial to reliability.
4.2.2. Heat dissipation and power dissipation resistance (R1): when charging with large current (especially when the input voltage VCC is high), it is recommended to connect one in series at the VCC input terminal.0.3Ω to 0.6Ω, rated powerMore than 0.15WSmall resistance. This resistor can share part of the voltage drop and power consumption, reduce the temperature rise of the chip, make the charging current more stable, and improve the overall reliability of the system.The optimal efficiency of VCC voltage at about 4.8V.
4.2.3. PCB layout Golden Rule:
·Power loop minimization: the wiring connecting VCC input capacitor, chip VCC/BAT pin and battery should be short and thick.
·Enhanced grounding and heat dissipation: GND pin is connected to large area ground copper foil. It is the most effective copper foil to expand the heat-dissipating method area connected to the VCC, BAT and GND pins of the chip as much as possible and connect them to the ground plane of the inner layer or the underlying layer through multiple vias.
·Sensitive signal isolation: signal routing such as PROG, CHRG, STDBY should be far away from power routing.
4.3. Flexible application of status indicator:
CHRG and STDBY pins can directly drive LED (Series current limiting resistor, such as 1kΩ) to realize intuitive traffic light indication (charging-red light on, full-green light on). It can also be connected to the GPIO of MCU through pull-up resistor, and the charging state can be read by software to realize more intelligent control.
V. Why choose JTM-IC CXLB73337?
JTM-IC is always committed to providing customers with high reliability and cost-effective power management solutions. CXLB73337 embodies our technological crystallization in the field of battery management:
·Differentiated competitive advantage: UniqueDouble Reverse connection protectionFunction constitutes a significant product safety barrier.
·Design friendliness: few peripheral components, clear indication logic, and comprehensive internal protection greatly shorten the development cycle and reduce BOM costs.
·Quality and Reliability Assurance: The product has been strictly tested and verified, and its performance parameters are guaranteed in the industrial temperature range of-40℃ to 85℃, which is suitable for demanding application scenarios.
VI. Packaging and pin functions
VII. Typical applications:
VI. Conclusion
Today, when safety and convenience are equally important, CXLB73337 sets a new benchmark for single lithium battery charging design. It is not only a charger, but also aPower security manager with multiple active protection. Whether developing the latest TWS headphones, smart wearable devices, or upgrading traditional portable electronic products, choosing CXLB73337 means choosingPeace of mind, peace of mind and confidence.
Visit JTM-IC official website now (jtm-ic.com), obtain the complete data Manual, detailed application notes, typical application circuit diagram, PCB layout reference and application samples of CXLB73337. Our professional technical support team is ready to assist you in the whole process from selection to mass production. Join hands with JTM-IC to inject safe and efficient energy core into your products!
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