BCM384x120y1K5ACz
Signal Characteristics (Cont.)
Specifications apply over all line, load conditions, unless otherwise noted; Boldface specifications apply over the temperature range of -40°C ≤ TINTERNAL
≤ 125°C (T-Grade); All other specifications are at TINTERNAL = 25ºC unless otherwise noted.
Auxiliary Voltage Source
• The VAUX pin is a standard analog I/O configured as an output from an internal µC.
• VAUX is internally connected to µC output as internally pulled high to a 3.3 V regulator with 2% tolerance, a 1% resistor of 1.5 kΩ.
• VAUX can be used as a "Ready to process full power" flag. This pin transitions VAUX voltage after a 2 ms delay from the start of powertrain activating,
signaling the end of softstart.
• VAUX can be used as "Fault flag". This pin is pulled low internally when a fault protection is detected.
SIGNAL TYPE
STATE
ATTRIBUTE
SYMBOL
CONDITIONS / NOTES
MIN
2.8
TYP MAX UNIT
Powertrain active to VAUX
time
Startup
tVAUX
Powertrain active to VAUX High
2
ms
VAUX Voltage
VVAUX
IVAUX
3.3
4
V
VAUX Available Current
mA
50
ANALOG
OUTPUT
Regular
VAUX Voltage Ripple
VVAUX_PP
mV
µF
TINTERNAL ≤ 100ºC
100
Operation
VAUX Capacitance
(External)
CVAUX_EXT
0.01
VAUX Resistance (External)
VAUX Fault Response Time
RVAUX_EXT
tVAUX_FR
VPRI_DC < VµC_ACTIVE
1.5
kΩ
Fault
From fault to VVAUX = 2.8 V, CVAUX = 0 pF
10
µs
BCM® Bus Converter
Page 11 of 25
Rev 1.5
07/2015
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