Datasheet

L6460 Power bridges
Doc ID 17713 Rev 1 77/139
the regulated current: the voltage provided at the I
REF_FB
pin will be compared to the
internal reference. L6460 has the possibility to choose between four voltage references
using the serial interface, writing the SelCurrRef[1:0] bits in the Aux3SwCfg1 register.
Regardless of the CurrRef voltage, if the I
REF_FB
pin remains below the chosen threshold,
the internal current limitation will work (typical Ilimit current 4A).
The battery charge profile can be chosen by fixing the desired CurrRef and FBRef internal
reference voltages and by choosing the desired V = f(I) trans-characteristic of the external
differential amplifier.
In the Figure 22 is shown a typical Li-Ion battery charge profile.
Figure 22. Li-ion battery charge profile
The battery charge loop control can be used to implement a buck type switching regulator.
The regulated output voltage will be externally set by a resistor divider network connected to
V
REF_FB
pin, as already described and the current protection will be the one implemented
internally in the Bridge4 section.
Rapid charge
phase
Time
Voltage or Current
Blue=Battery Voltage
Red=Battery Current
FBRef depending
CurrRef depending
End Of Charge Precharge
phase
Ichrg
Iprechrg
Vchrg
Veochrg
Ieochrg
Constant V.
phase