iC-MFL / iC-MFLT
8-/12-FOLD FAIL-SAFE LOGIC N-FET DRIVER
Rev C1, Page 9/13
DESCRIPTION OF FUNCTIONS
Output characteristic of the lowside transistor
The lowside output transistors at the eight/twelve chan-
nels demonstrate a resistive behavior with low voltage
V(OUTx) and behave as a current sink with finite out-
put resistance with higher voltages.
I(OUTx)
[mA]
rent remains high until Vt()hi (Electrical Characteristics
No. 203); above this threshold the device switches to
a lower pull-down current. If the voltage falls below
Vt()lo (Electrical Characteristics No. 204), the device
switches back to a higher pull-down current.
I(OUTx)
[mA]
VCC − V(OUTx)
3.6
1
2
3
4
5
[V]
−400Ω
−400Ω
V(OUTx)
[V]
−3
1
2
3
4
5
Figure 2: Output characteristic of the lowside tran-
sistor at OUTx
Output characteristic for the highside transistor
The highside output transistors at the eight/twelve
channels demonstrate a resistive behavior with low
voltage (VCC – V(OUTx)) and behave as a current
source with finite output resistance with higher volt-
ages.
Pull-down currents
In order to enhance noise immunity with limited power
dissipation at inputs INx and EN the pull-down cur-
rents at these pins have two stages. With a rise in
voltage at input pins INx and EN the pull-down cur-
Figure 3: Output characteristic of the highside tran-
sistor at OUTx
Ipd()
V() increasing
Ipd1()
Ipd2()
V() decreasing
Vt()lo
Vt()hi
V()
Figure 4: Pull-down currents at INx and EN
ICHAUS [ IC-HAUS GMBH ]
