Ni-MH battery charger using LT4060

Description: This circuit diagram represents a highly efficient Ni-MH battery charger utilizing the LT4060 integrated circuit from Linear Technologies. The circuit can also accommodate Ni-Cd batteries with minor modifications. To charge Ni-Cd batteries, the CHEM pin (pin 12) of the IC should be connected to +Vcc. The configuration is designed to charge two cells connected in series. By adjusting the connections of the SEL0 and SEL1 pins, the circuit can charge up to four batteries in series. For a single cell, both SEL0 and SEL1 pins should be grounded. For two cells, SEL1 should be grounded while SEL0 is connected to Vcc. For three cells, SEL1 is connected to Vcc and SEL0 is grounded. For charging four cells, both SEL0 and SEL1 pins should be connected to Vcc. Additionally, the circuit incorporates temperature-based charge qualification, with an NTC thermistor connected to the NTC pin (pin 11) of the IC acting as the temperature sensor.

The LT4060 integrated circuit is designed specifically for charging nickel-metal hydride (Ni-MH) and nickel-cadmium (Ni-Cd) batteries, providing a robust solution for battery management. The charger operates efficiently by utilizing a constant current and constant voltage charging approach, which is essential for prolonging battery life and ensuring safety during the charging process.

The circuit's flexibility allows for the charging of one to four cells in series, which is facilitated by the SEL0 and SEL1 pins. This configurability makes the LT4060 charger suitable for various applications, including consumer electronics and portable devices. The connections for these pins are critical; grounding both SEL0 and SEL1 is necessary for single-cell charging, while different combinations of Vcc and GND connections enable the charging of two, three, or four cells.

The inclusion of the CHEM pin allows the user to switch between charging Ni-MH and Ni-Cd batteries, enhancing the circuit's versatility. When charging Ni-Cd batteries, connecting the CHEM pin to Vcc modifies the charging parameters to accommodate the specific needs of these cells.

Temperature monitoring is a vital feature of this circuit, as it helps prevent overheating and potential damage to the batteries. The NTC thermistor connected to the NTC pin provides real-time temperature feedback, allowing the LT4060 to adjust the charging current based on the detected temperature. This feature is crucial for maintaining optimal charging conditions, particularly in environments where temperature fluctuations are common.

Overall, the LT4060 battery charger circuit offers a powerful and adaptable solution for charging Ni-MH and Ni-Cd batteries, combining efficiency, safety, and flexibility in one comprehensive design.This is the circuit diagram of a very powerful and efficient Ni-MH battery charger using IC LT4060 from Linear Technologies. In addition to Ni-MH batteries Ni-Cd batteries can be also charged by slightly modifying the circuit.

For charging Ni-Cd batteries connect the CHEM pin (pin12) of the IC to +Vcc. Here the circuit is configured to charge 2 cell s connected in series. By altering the connections of SEL0 and SEL1 pins, upto 4 batteries in series can be charged using this circuit. For charging a single cell, connect SEL0 and SEL1 pins to GND. For charging two cells, connect SEL1 to GND and SEL0 to Vcc. For charging three cells, connect SEL1 to VCC and SEL0 to GND. For charging 4 cells, connect SEL0 and SEL1 pins to VCC. The circuit also features temperature based charge qualification. An NTC thermistor connected at the NTC pin (pin11) of the IC serves as the temperature sensor.