ST92141 STMicroelectronics, ST92141 Datasheet - Page 78

• Manufacturer Part Number: ST92141
• Description: 8/16-bit Mcu For 3-phase Ac Motor Control
• Manufacturer: STMicroelectronics

ST92141 - RESET AND CLOCK CONTROL UNIT (RCCU)
5.8 LOW VOLTAGE DETECTOR (LVD)
To allow the integration of power management
features in the application, the Low Voltage Detec-
tor function (LVD) generates a static reset when
the V
value. This means that it secures the power-up as
well as the power-down keeping the ST9 in reset.
The V
lower than the V
in order to avoid a parasitic reset when the MCU
starts running and sinks current on the supply
(hysteresis).
The LVD Reset circuitry generates a reset when
V
Figure 40. Low Voltage Detector vs Reset
78/179
DD
– V
– V
RESET
1
is below:
DD
LVDr
LVDf
LVDf
V
V
LVDr
LVDf
supply voltage is below a V
when V
when V
reference value for a voltage drop is
V
DD
LVDr
DD
DD
reference value for power-on
is falling
is rising
LVDf
reference
HYSTERISIS
V
The LVD function is illustrated in
Provided the minimum V
the oscillator frequency) is below V
can only be in two modes:
In these conditions, secure operation is always en-
sured for the application without the need for ex-
ternal reset hardware.
LVDhyst
– under full software control
– in static safe reset
DD
value (guaranteed for
Figure
LVDf
, the MCU
40.