September 2013 Rev 6 1/17
1
L9349-LF
Quad intelligent power low side switch
■ Four low-side output driver with protection
diagnostics designed as a conventional switch
– 2 channels with 5 A output current
capability and r
ON
= 0.2 typ.
– 2 channels with 3 A output current
capability and r
ON
= 0.3 typ.
■ Integrated 60 V Zener diodes output clamping
structure
■ Output slope control
■ Short circuit protection
■ Open load detection in ON and OFF condition
■ Load bypass detection
■ Overload disable
■ Signal and power ground loss shutdown
■ Selective overtemperature shutdown
■ Electrostatic discharge (ESD) protection
Description
The L9349 is a monolithic IC designed to drive
inductive loads in low side configurations like
hydraulic valves used in ABS systems.
Particular care has been taken to protect the
device against failures, to avoid electromagnetic
interferences and to offer extensive real time
diagnostics.
The internal pull down current source at the
ENable and INput pins assures, that the device is
switched off, in case of open input conditions.
An output voltage slope limitation is implemented
to reduce the EMI.
The device is equipped with an integrated Zener
diodes clamp for fast inductive load current
recirculation. This structure limits the output
voltage during the recirculation phase to 50V.
The device is self-protected against short circuit
at the outputs and overtemperature.
For the real time error diagnosis, the voltage and
the current of the outputs are compared with
internally fixed thresholds to recognize open load
in OFF and ON conditions.
The output voltages are also compared with each
other in OFF condition with a fixed offset, in order
to recognize load bypasses.
If the over load current threshold is exceeded, the
output current will be limited internally during the
diagnostic overload delay switch-off time.
All four channels are monitored with a status
output. The diagnostic output level in connection
with different enable and input conditions allows it
to recognize the different fail states.
Table 1. Device summary
Order code Package
(1)
1. ECOPACK® package (see Section 4: Package information)
Packing
L9349-LF PowerSO-20 Tray
L9349TR-LF PowerSO-20 Tape and reel
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