L6482
Functional description
Doc ID 023768 Rev 1
29/73
6.11
VS undervoltage lockout (UVLO_ADC)
The device provides an undervoltage signal of the integrated ADC input voltage (the
UVLO_ADC flag in the STATUS register). When V
ADCIN
falls below the V
ADC,UVLO
value, the
UVLO_ADC flag is forced low and it is kept in this state until the ADCIN voltage is greater
than V
ADC,UVLO
and a GetStatus command is sent to the device.
The ADCIN undervoltage event does not turn off the gates of the power bridges.
The motor supply voltage undervoltage detection can be performed by means of this
feature, connecting the ADCIN pin to VS through a voltage divider.
6.12
Thermal warning and thermal shutdown
An integrated sensor allows detection of the internal temperature and implementation of a 3-
level protection.
When the T
j(WRN)Set
threshold is reached, a warning signal is generated. This is the thermal
warning condition and it expires when the temperature falls below the T
j(WRN)Rel
threshold.
When the T
j(OFF)Set
threshold is reached, all the gates are turned off and the gate driving
circuitry is disabled (Miller clamps are still operative). This condition expires when the
temperature falls below the T
j(OFF)Rel
threshold.
When the T
j(SD)OFF
threshold is reached, all the gates are turned off using Miller clamps, the
internal V
CC
voltage regulator is disabled and the current capability of the internal V
REG
voltage regulator is reduced (thermal shutdown). In this condition, logic is still active (if
supplied). The thermal shutdown condition only expires when the temperature goes below
T
j(SD)ON
.
The thermal condition of the device is shown by TH_STATUS bits in the STATUS register
(
Table 9.
UVLO thresholds
UVLOVAL
0
1
Low-side gate driver supply turn-off threshold
(V
CCthOff
)
6.3 V
10 V
Low-side gate driver supply turn-on threshold
(V
CCthOn
)
6.9 V
10.4 V
High-side gate driver supply turn-off threshold
(
Δ
V
BOOTthOff
)
5.5 V
8.8 V
High-side gate driver supply turn-on threshold
(
Δ
V
BOOTthOff
)
6 V
9.2 V
