■Overview
The < MM3458 > comes with an external power transistor and reverse current prevention circuit built into a compact PLP-10 package (2.7 x 2.5 x 0.6mm).
Since no sensing resistor is required, the charging circuit can be built with a small number of components.
In November 2008, "Lithium Ion Batteries" were added to a group of electrical appliances outside those specified in the Product Safety Electrical Appliance and Material Law (PSE Law), and technical standards are set to rise from November 2011.
Thus, to safely control the charging of the battery Mitsumi have implemented a method by which the charging current and voltage are both controlled according to temperature data from a thermistor.
A function to detect rises in IC temperature during high-power charging is also included to allow charging at the optimal charging rate for any given temperature.
§ Features
1. | Predicting the need for compliance with the PSE law due for introduction in 2011, the <MM3458 > ensures safe operation through built-in battery temperature monitoring/control functions and charging current/charging voltage control at high and low battery temperatures. |
2. | Since no external power transistor, reverse current prevention diode or sensing resistor is required, the number of components and the amount of generated heat can be reduced. |
3. | Threshold values can be set with external resistors for preliminary current, high-speed charging current and charging termination current (max. charging current 1.5A) |
4. | IC temperature rises limited by chip temperature detection function. This enables charging at optimal charging rate. |
5. | The charging timer is built in, and the timer timing can be set using an external resistor. |
§ Main specifications
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Supply Voltage |
4.0~6.0V |
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Charging Control Voltage |
4.2V±30mV (0.7%) |
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High-Speed Charging Current |
558mA±5% (RICHG=2.32kΩ) |
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Series Path Resistance when Tr is ON |
0.38Ω typ. |
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Charging Timer |
60 min. (preliminary), 300 min. (high-speed) |
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Battery Temperature Detection |
2°C (Low), 43°C (High) |
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Chip Temperature Detection |
93°C typ. |
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Thermal Shutdown |
153°C typ. |
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Package |
PLP-10 |
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Dimensions |
2.7×2.5×0.6 (Unit:mm) |
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