FUNCTIONAL DEVICE OPERATION
PROTECTION AND DIAGNOSIS FEATURES
Table 8. Device Behavior in Case of Under-voltage
High Side
UV Disable
IN = 0
(Falling or
UV Disable
IN∗∗∗ = 1
(Falling or
UV Enable
IN = 0
UV Enable
IN = 0
UV Enable
IN∗∗∗ = 1
UV Enable
IN∗∗∗ = 1
Switch
(VPWR Battery
Voltage)∗∗
State
(Falling VPWR) (Rising VPWR) (Falling VPWR) (Rising VPWR)
Rising VPWR) Rising VPWR)
VPWR >
VPWRUV
Output State
FS State
OFF
OFF
ON
1
OFF
OFF
ON
1
1
0
1
0
1
1
0
SPI Fault
Register UVF
Bit
1 until next read
0
0
VPWRUV >
VPWR >
UVPOR
Output State
FS State
OFF
OFF
OFF
OFF
OFF
ON
1
0
1
0
1
0
1
0
1
1
0
SPI Fault
Register UVF
Bit
0
UVPOR >
VPWR > 2.5 V∗
Output State
FS State
OFF
OFF
OFF
1
OFF
1
OFF
ON
1
1
1
1
1
0
SPI Fault
Register UVF
Bit
1 until next read
1 until next read 1 until next read
0
2.5 V > VPWR > Output State
OFF
1
OFF
1
OFF
1
OFF
1
OFF
OFF
0 V
FS State
1
0
1
0
SPI Fault
Register UVF
Bit
1 until next read 1 until next read 1 until next read 1 until next read
Comments
UV fault is
not latched
UV fault is
not latched
UV fault
is latched
∗ Typical value; not guaranteed
∗∗ While VDD remains within specified range.
∗∗∗ = IN is equivalent to IN direct input or IN_spi SPI input.
REVERSE BATTERY
GROUND DISCONNECT PROTECTION
The output survives the application of reverse voltage as
low as -16 V. Under these conditions, the output’s gate is
enhanced to keep the junction temperature less than 150°C.
The ON resistance of the output is fairly similar to that in the
Normal mode. No additional passive components are
required.
In the event the 33982 ground is disconnected from load
ground, the device protects itself and safely turns OFF the
output regardless the state of the output at the time of
disconnection. A 10 kΩ resistor needs to be added between
the WAKE pin and the rest of the circuitry in order to ensure
that the device turns off in case of ground disconnect and to
prevent this pin to exceed its maximum ratings.
33982
Analog Integrated Circuit Device Data
Freescale Semiconductor
21
FREESCALE [ Freescale ]
