MICRONE ME4068ASPG

ME4068 is a lithium battery charge management IC featuring constant-current/constant-voltage (CC/CV) charging mode, capable of rapidly and efficiently charging single-cell (4.2V/4.35V) lithium batteries. It employs a current-mode PWM buck switching control architecture, providing a compact, simple, and efficient solution for fast lithium battery charging. ME4068 integrates an anti-backflow function, eliminating the need for an input protection diode in practical applications. ME4068 sets high-accuracy charging current via an external sense resistor. Internally, a resistor divider and precision reference voltage set the float voltage for a single cell (4.2V/4.35V) with up to ±1% accuracy. When the input power is removed, the IC automatically enters a low-current sleep mode, reducing battery leakage current to as low as 3μA. When the charging cycle ends, if the single-cell voltage drops below 4.1V/4.25V, the IC will automatically reinitiate charging. The IC also features a charge timer protection function, automatically shutting down after 6 hours of charging. ME4068 is a CC/CV lithium battery charge controller based on a current-mode PWM buck switching architecture. The charging current is set by a sense resistor connected between the SEN and BAT pins. The float voltage for a single cell is internally set to 4.20V/4.35V. For lithium batteries requiring high-precision float voltage, the integrated reference voltage, error amplifier, and resistor divider provide high-accuracy regulation of the float voltage. The charging cycle begins when the VIN input voltage exceeds the battery voltage by more than 100mV. At the start of the charging cycle, if the battery voltage is below the trickle charge threshold, the charger enters trickle charge mode, with the trickle charge current internally set to 10% of the full charge current. Once the battery voltage exceeds the trickle charge threshold, the charger enters full-current CC mode. In CC mode, the charging current is set by the external sense resistor Rs and an internal 100mV reference voltage: I_OUT = 100mV/Rs. As the battery voltage approaches the float voltage, the charging current begins to decrease. When the charging current drops to 10% of the full charge current, an internal comparator turns off the pull-down N-channel MOSFET at the CHRG pin, indicating that the charge cycle is approaching termination. To restart the charging cycle, the input voltage can be removed and reapplied, or the charger can be briefly disabled. Similarly, a new charging cycle begins when the single-cell voltage drops below the recharge threshold voltage. Once the battery is fully charged, if the input voltage remains applied, the charger shuts down; when the input voltage is removed, the charger enters sleep mode, significantly reducing battery current consumption and extending standby time. The TEMP pin connects to a negative temperature coefficient (NTC) resistor to GND to monitor whether the battery temperature is within the acceptable range. If the temperature goes outside the 0~50°C range, the charging cycle will be suspended. If the temperature detection function is not required, connect a 20KΩ resistor directly to GND.

• Input voltage range: 4.7V~14V
• Built-in reverse current protection
• Built-in input adaptive function (ME4068A)
• Built-in soft-start to prevent large inrush current at power-up
• High-efficiency current-mode PWM buck switching control architecture
• ±10% charge current accuracy
• Fixed switching frequency for minimum noise
• ±1% charge voltage accuracy
• Automatic recharge
• Charge timer: 6 hours
• Automatic sleep mode upon input power removal
• Automatic trickle charge mode when battery voltage is low
• Stable output with low-ESR ceramic capacitors
• Battery temperature detection

• Charging equipment
• Portable laptops
• Handheld devices