Functional description L9339
10/14
4 Functional description
The L9339 is a quad low side driver for lines, lamps or inductive loads in automotive and
industrial applications.
The logic input levels are TTL and CMOS compatible. This allows the device to be driven
directly by a microcontroller. For the noise immunity, all input thresholds has a hysteresis of
typ. 100 mV. At each input (IN and PRG) voltages from -0.3 V to 32 V can be applied, EN
can withstand voltages from -25 V to 3 2 V. The device is activated with a 'high' signal on
ENable. ENable 'low' switches the device into the sleep mode. In this mode the quiescent
current is less than 10 µA. A high signal on PRoGramming input changes the signal transfer
polarity from non inverting into the inverting mode. This pin can be connected to V
S
or GND.
The forced status of the PRG and EN pin is low, if these pins are not connected. This forced
condition leads to a mode change if the PRG pin was high before the interruption.
Independent of the PRoGramming input, the OUTput switches off, if the signal INput pin is
not connected.
Each output driver has a current limitation of min 0.4 A and a independent thermal shut-
down. The thermal shut-down deactivates that output, which exceeds temperature switch off
level. When the junction temperature decreases 20 K below this temperature threshold the
output will be activated again (hysteresis of the thermal shutdown function). The slew rate
of the output voltage is limited to max. 14 V/µs, to reduce the electromagnetic radiation of
the loads and its wiring. For inductive loads a output voltage clamp of typically 52 V is
implemented.
The DIAGnostic is an open drain output with an additional series diode. The logic status
depends on the PRoGramming pin. If the PRG pin is 'low' the DIAG output becomes low, if
the device works correctly. At thermal shut-down of one channel the DIAGnostic output
becomes high. If the PRG pin is 'high' this output is switched off at normal function and
switched on at over temperature.
Table 6. Diagnostic
Pins EN PRG IN OUT DIAG
Correct function
H L L L (on) L (on)
H L H H (off) L (on)
H H L H (off) H (off)
H H H L (on) H (off)
L X X H (off) H (off)
Over temperature or
supply voltage
H L X H (off)
(1)
1. Selective for each channel at over temperature
X = not relevant
H = high
L = low
H (off)
Over temperature H H X H (off)
(1)
L (on)
