IC-MFL Datasheet, PDF (2/13 Pages) IC-Haus GmbH – 8-/12-FOLD FAIL-SAFE LOGIC N-FET DRIVER

iC-MFL / iC-MFLT
8-/12-FOLD FAIL-SAFE LOGIC N-FET DRIVER
Rev C1, Page 2/13
DESCRIPTION
iC-MFL / iC-MFLT is a monolithically integrated,
8/12-channel level adjustment device which drives
N-channel FETs. The internal circuit blocks have
been designed in such a way that with single er-
rors, such as open pins (VCC, GND, GNDR) or
the short-circuiting of two outputs, iC-MFL’s output
stages switch to a predefined, safe low state. Exter-
nally connected N-channel FET are thus shut down
safely in the event of a single error.
The inputs of the eight/twelve channels consist of
a Schmitt trigger with a pull-down current source
and are compatible with TTL and CMOS levels (1.8
to 5 V). The eight/twelve channels have a current-
limited push-pull output stage and a pull-down resis-
tor at the output. The output stages supply an output
signal of 5 V and are enabled by a high signal at pin
EN. Furthermore, all stages can handle surge volt-
age pulses (max. 18 V, pulse width < 100 ms, max.
2 % duty cycle) at the output.
iC-MFL monitors the supply voltage at VCC pin and
the voltages at the two ground pins GND and GNDR.
The pins GND and GNDR must be connected to-
gether externally in order to guarantee the safe low
state of the output stages in the event of error.
Should the supply voltage at VCC undershoot a pre-
defined threshold, the voltage monitor causes the
outputs to be actively tied to GND via the lowside
transistors. If the supply voltage ceases to be applied
to VCC, the outputs are tied to GNDR by pull-down
resistors.
If the connection between the ground potential and
the GND pin is disrupted, the highside and lowside
transistors of the output stages are shut down and
the outputs tied to GNDR via the pull-down resistors.
If on the other hand the connection between ground
potential and the GNDR pin is disrupted, only the
output stage highside transistors are shut down; the
outputs are then actively tied to GND via the lowside
transistors.
Open inputs IN1...8/12 and EN are actively tied to
GND by pull-down currents. The pull-down currents
have two stages in order to limit power dissipation
with enhanced noise immunity.
When two outputs of different logic states are short
circuited, the driving capability of the lowside driver
predominates, keeping the connected N-channel
FETs in a safe shutdown state.
The device is protected against destruction by ESD.
PACKAGES