IC-MFN Datasheet, PDF (9/13 Pages) IC-Haus GmbH – 8-FOLD FAIL-SAFE N-FET DRIVER

iC-MFN
8-FOLD FAIL-SAFE N-FET DRIVER
DESCRIPTION OF FUNCTIONS
Rev A2, Page 9/13
Hi-level output configuration
The device iC-MFN has three adjustable hi-levels for
driving N-channel fets. The configured hi-level is com-
mon to all outputs OUTx and the maxmimum level is
the power supply VB potential. The hi-level configura-
tion inputs are used simultaneous for enabling the hi-
level at the outputs OUTx. The hi-level at exactly one
input EN5, EN10 or ENFS configure the voltage of hi-
level and enable the outputs. If more than one of these
inputs have hi-level the outputs remains disabled. The
hi-level 5 V (configured with EN5 = hi) and 10 V (con-
figured with EN10 = hi) are internally generated by a
voltage reference and regulated. The hi-level VB (con-
figured with ENFS = hi) is an unregulated connection
to VB. In this case the voltage swing depends directly
from the power supply VB.
Output characteristics of the highside transistor
The highside output transistors at the eight channels
demonstrate a resistive behavior with low voltage (VB
– V(OUTx)) and behave as a current source with finite
output resistance with higher voltages.
I(OUTx)
[mA]
3.6
−2.5
−2
−1.5
−1
−0.5
165 Ω
V(OUTx)−Vr(OUTx)
0.5
1
1.5
2
2.5 ^[V]
−3
Figure 3: Output characteristic of the regulated
push-pull-output at OUTx
Output characteristic of the lowside transistor
The lowside output transistors at the eight channels
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]
3.6
I(OUTx)
[mA]
VB − V(OUTx)
1
2
3
4
5
[V]
−400Ω
−3
Figure 2: Output characteristic of the highside tran-
sistor at OUTx
400 Ω
V(OUTx)
1
2
3
4
5 ^[V]
Figure 4: Output characteristic of the lowside tran-
sistor at OUTx
Status output NOK
The status output NOK is a current limited 40 V proof
open-drain output. The output transistor is switched
on if the hi-level of the outputs OUTx are enabled with
exactly one pin ENx, the outputs have reached the volt-
age levels defined by the inputs INx, the power supply
voltage is above the power-on threshold, the tempera-
ture is below the switch off temperature and all power
supply pins are connected.
Output characteristic of the regulated push-pull-
output at OUTx
The hi-level 5 V and 10 V is generated with a regulated
push-pull output and demonstrate a resistive behav-
ior with low voltage changes and behave as a current
source with finite output resistance with higher voltage
changes.