STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Data Sheet

Doc ID 17713 Rev 1

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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 

 is shown a typical 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