STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Fiche De Données
Codes de produits
EVAL6460
Power bridges
L6460
76/139
Doc ID 17713 Rev 1
14.1.8
Battery charger or switching regulator (Bridge 4)
The functionality of this circuit is obtained by using the bridge 4 output stage. This circuit is
powered directly from
powered directly from
V
Supply
and it is intended to be used as a battery charger or a
switching regulator.
The control loop block diagram is shown in the
.
Figure 21.
Battery charger control loop block diagram
The battery charger control loop implements an asynchronous switching regulator intended
to be used as a constant voltage/constant current programmable source.
to be used as a constant voltage/constant current programmable source.
When used as a simple switching regulator, it could be a system regulator depending on
startup configurations
startup configurations
When a system regulator under-voltage event is detected L6460 will enter in reset state
signaling this event to the microcontroller by pulling low the nRESET pin and disabling most
of its internal blocks.
signaling this event to the microcontroller by pulling low the nRESET pin and disabling most
of its internal blocks.
When the control loop is intended to be used as a battery charger, the Aux3BatteryCharge
bit must be written in the Aux3SwCfg1 register. This is because in this case the
undervoltage event that will be sure present when charging a battery (see battery charger
profile in
bit must be written in the Aux3SwCfg1 register. This is because in this case the
undervoltage event that will be sure present when charging a battery (see battery charger
profile in
) will not be considered during start up sequence.
The regulated output voltage will be externally set by a resistor divider network connected to
V
V
REF_FB
pin. L6460 has the possibility to choose between four voltage references (and, as a
consequence, four under-voltage thresholds) using the serial interface. The feedback
reference voltage selection is made by writing the SelFBRef[1:0] bits in the Aux3SwCfg1
register.
reference voltage selection is made by writing the SelFBRef[1:0] bits in the Aux3SwCfg1
register.
The regulation of the output current can be done externally, by using a sense resistor
connected in series on the path that provides current to the load. By using an external
differential amplifier the customer can set the desired V = f(I) characteristic, and therefore
connected in series on the path that provides current to the load. By using an external
differential amplifier the customer can set the desired V = f(I) characteristic, and therefore
IREF_FB
VREF_FB
COMP_I
COMP_V
PULSE SKIPPING
BURST
CONTROL LOGIC
BURST
CONTROL LOGIC
PEAK CURRENT
MODE CONTROL
LOGIC
MODE CONTROL
LOGIC
BRIDGE 4
PARALLELED
POWER
STAGE
SelFBRef<1:0>
DC4_plus
DC4_minus
SelCurrRef<1:0>
DIFF
AMPLI
TO
LOAD
FBRef
CurrRef
Ilimit
PWM
L6460