STMicroelectronics FlexSPIN: SPI configurable stepper and DC multi motor driver evaluation board EVAL6460 EVAL6460 Data Sheet
Product codes
EVAL6460
L6460
Start-up configurations
Doc ID 17713 Rev 1
41/139
8.3 Slave
device
mode
In slave device mode, L6460 consider the nAWAKE pin as an input enable. Since this is now
a digital pin, the current pull up source inside the nAWAKE circuit is disabled.
a digital pin, the current pull up source inside the nAWAKE circuit is disabled.
At the startup, if the nAWAKE pin is found to be low for a period higher than t
AWAKEFILT
,
L6460 enters directly in the “Low Power mode”; when nAWAKE pin is pulled high for a
period higher than t
period higher than t
AWAKEFILT
, L6460 begins its start up procedure.
8.4
Master device mode
In master device mode, L6460 begins its start up procedure without waiting for any external
enable signal and it uses GPIO[5] pin to drive the nAWAKE pin of Slave devices.
enable signal and it uses GPIO[5] pin to drive the nAWAKE pin of Slave devices.
During the whole start up time, it forces its GPIO[5] pin at logic level “0” in order to maintain
all slave devices in “Low Power mode” as previously described. When start up operations
are completed, L6460 forces the GPIO[5] output to logic level “1” to enable the slave devices
and keeps GPIO[5] output at high level until it senses an under-voltage on any of its System
regulators. If firmware writes in the PwrCtrl register to set Master L6460 in “Low Power
mode” it immediately forces GPIO[5] output to logic level “0” to force the slave devices to
enter in “Low Power mode”, then it waits for T
all slave devices in “Low Power mode” as previously described. When start up operations
are completed, L6460 forces the GPIO[5] output to logic level “1” to enable the slave devices
and keeps GPIO[5] output at high level until it senses an under-voltage on any of its System
regulators. If firmware writes in the PwrCtrl register to set Master L6460 in “Low Power
mode” it immediately forces GPIO[5] output to logic level “0” to force the slave devices to
enter in “Low Power mode”, then it waits for T
MASTWAIT
time and it starts its “Low Power
mode” sequence.
8.5 Single
device
mode
In single device mode, the device behaves similarly to master device mode but:
1.
It doesn’t use the GPIO[5] pin to drive slave devices.
2.
It doesn’t wait for T
MASTWAIT
before entering in “Low Power mode”.
8.6
Sub-configurations for slave, master or single device modes
Each slave, master or single device modes can be divided in other minor modes depending
on the start-up sequence needed for L6460 internal regulators.
on the start-up sequence needed for L6460 internal regulators.
Unless otherwise specified, in all the following modes the regulators included in the start up
sequence are considered system regulators and they start in the sequence indicated.
sequence are considered system regulators and they start in the sequence indicated.
8.6.1 Bridge
mode
In this configuration bridges 3 and 4 are not used as regulators and therefore can be
configured by the firmware in any of their possible bridge modes.
configured by the firmware in any of their possible bridge modes.
When in this mode the power-up sequence is:
1.
Main switching regulator (V
SWmain
).
2.
Main linear regulator (V
LINmain
).