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

   

   

   

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 Doc ID 17713 Rev 1

When this control loop is intended to be used as a simple buck regulator, the proper 
Aux3BatteryCharge bit must be written in the Aux3SwCfg1 register.

The regulator will also implement a soft start strategy.

When L6460 “low power mode” is enabled this regulator will be disabled.

Here after are summarized the primary features of the regulator:

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Internal power switch.

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Nonlinear pulse skipping control.

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Internally generated PWM (250 KHz switching frequency).

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Cycle by cycle current limiting using internal current sensor/ external current 
sense differential amplifier.

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Protected against load short circuit.

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Soft start circuitry to limit inrush current flow from primary supply.

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Under voltage signal (both continuous and latched) accessible through SPI.

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Over temperature protection.

In pulse skipping control PWM the duty cycle must be decided by the user depending on 
supply voltage and regulated voltage.

Therefore the switching regulator has 4 possible PWM duty cycles that can be changed 
writing in the Aux3PWMTable[1:0] bits in the Aux3SwCfg1 register according to the 

.

IREF_FB

VREF_FB

COMP_I

COMP_V

PULSE SKIPPING
BURST
CONTROL LOGIC

PEAK CURRENT
MODE CONTROL
LOGIC

BRIDGE 4

PARALLELED

POWER

STAGE

SelFBRef<1:0>

DC4_plus

DC4_minus

SelCurrRef<1:0>

TO

LOAD

FBRef

CurrRef

Ilimit

PWM

L6460