Functional description
powerSTEP01
Table 8. UVLO thresholds
UVLOVAL
0
1
Low-side gate driver supply turn-off threshold
(VCCthOff
6.3 V
6.9 V
5.5 V
6 V
10 V
)
Low-side gate driver supply turn-on threshold
(VCCthOn
10.4 V
8.8 V
9.2 V
)
High-side gate driver supply turn-off threshold
(DVBOOTthOff
)
High-side gate driver supply turn-on threshold
(DVBOOTthOff
)
7.11
V undervoltage lockout (UVLO_ADC)
S
The device provides an undervoltage signal of the integrated ADC input voltage (the
UVLO_ADC flag in the STATUS register). When VADCIN falls below the VADC,UVLO value the
UVLO_ADC flag is forced low and it is kept in this state until the ADCIN voltage is greater
than VADC,UVLO and a GetStatus command is sent to the device.
The ADCIN undervoltage event doesn’t turn off 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 as described in
Section 8.5.
7.12
Thermal warning and thermal shutdown
An integrated sensor allows detection of the internal temperature and implementation of a 3-
level protection.
When the Tj(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 Tj(WRN)Rel threshold.
When the Tj(OFF)Set threshold is reached, all the MOSFETs are turned off and the gate
driving circuitry is disabled (Miller clamps are still operative). This condition expires when
the temperature falls below the Tj(OFF)Rel threshold.
When the Tj(SD)OFF threshold is reached, all the MOSFETs are turned off using Miller
clamps, the internal VCC voltage regulator is disabled and the current capability of the
internal VREG 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 Tj(SD)ON
.
The thermal condition of the device is shown by TH_STATUS bits in the STATUS register
(Table 9).
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STMICROELECTRONICS [ ST ]
