Overview: MITSUMI Protection of Lithium Ion Batteries (one cell) MM1291 Protection of Lithium Ion Batteries (one cell) Monolithic IC MM1291
Outline
This is a protection IC for one-cell series that protects lithium ion batteries during excess charging, discharging, or overcurrent. If abnormalities occur during charging and excess voltage is applied, it has a function that turns off the external FET switch when voltage is applied to each battery beyond a specified time (overcharging detection). It also has a function that turns off the external FET switch when the voltage for each battery falls below a set voltage, to prevent excess discharge when discharging the battery (discharging detection). At that time, the IC is switched to low current consumption mode. Also, when there is a large current flow due to shorting or other reasons, there is a functions for turning off the external FET switch (overcurrent detection). These function prise a protection circuit, with few external parts, for lithium ion batteries. 1-Cell Protection ICs
Overcharge detection SOP-8 VSOP-8 voltage MM1291AF AW 4.35V BF BW 4.25V CF 4.10V DF 4.35V EF 4.35V GF 4.225V HF HW 4.35V JW 4.25V KF 4.25V MW 4.30V Package Hysteresis Dead time 200mV 200mV 25mV 25mV 27mV 27mV 200mV 270mV 200mV 270mV Overdischarge Release detection voltage Delay Overcurrent detection Detec time shot-mode No No No min. 5mS No No typ. 10mS No 0.45V max. 15mS 0.45V 0.9V 0.45V at Ctd= 0.082µF min. 0.5S typ. 1S max. 1.5S * * * * * * * 2.6V 2.4V 2.6V 2.4V 2.6V 2.4V 2.6V 2.4V 2.6V 2.4V 2.6V 2.4V 2.6V 2.4V 2.3V 2.3V 2.3V 2.9V 2.9V 2.9V 2.9V 2.9V 2.9V 2.9V 2.9V 2.9V 2.9V Overcurrent 100mV 100mV 150mV min. 5mS 100mV 100mV typ. 10mS 100mV 50mV max. 15mS 125mV 50mV 125mV Note : Under open-load conditions, returns to normal mode from overcurrent mode.
