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

L6460’s hibernate mode allows the firmware to switch off some (or all) selected System 
Regulators leaving in on state only those necessary to resume L6460 to operative condition 
when waked-up by an external signal.

Hibernate mode is selected when the firmware writes the command word in the 
HibernateCmd register. When in hibernate mode L6460 will force regulators in the state 
(on/off) selected by the firmware by writing in the HibernateCmd register and will force 
nRESET pin low.

The exiting from hibernate mode is achieved by forcing at low level nAWAKE pin (or GPIO5 
pin if L6460 is in Slave mode); L6460 will also exit from hibernate mode if an undervoltage 
event happens on V

Supply

, V

SupplyInt

, V

Pump

 or V

3v3

.

When the exit from hibernate mode is due to an external command, L6460 sets to ‘1’ the bit 
HibModeLth in the HibernateStatus register.

When in normal operating mode, the microcontroller can place L6460 in “Low Power mode”.

In this condition L6460 sets all bridges outputs in high impedance, powers down all 
regulators (including system regulators and charge pump) and disables almost all its circuits 
including internal clock reducing as much as possible power consumption.

The only circuits that remain active are:

–

V

3V3

 internal regulator.

–

nAWAKE pin current pull-up.

–

nRESET pin that will be pulled low.

–

POR circuit.

The entering in low power mode is obtained in different ways depending if L6460 is 
configured as slave device or not. When L6460 is configured as slave device the low power 
mode is directly controlled by nAWAKE pin that acts as an enable: if this pin is low for a time 
longer then t

AWAKEFILT

, Low Power mode is entered; if this pin is high L6460 exits from Low 

Power mode.

In all other start-up configurations, Low Power mode is entered by writing a Low Power 
mode command in the PowerModeControl register; once L6460 is in Low Power mode it 
starts checking the nAWAKE pin status: if it is found low for a time longer than t

AWAKEFILT

, 

L6460 exits from Low Power mode and restarts its startup sequence. When the nAWAKE 
pin is externally pulled low, the “AWAKE” event is stored and it is readable through SPI. 
L6460 will also exit from Low Power mode if a POR event is found.

At the start up, before L6460 has identified the required operation mode (see 

), a 

current sink I

INP 

is always active to pull down nAWAKE pin. As soon as the operation mode 

(basic, slave, master or single device) is detected, the functionality of nAWAKE pin will be 
different.