OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

L9954LXPTR

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24P25-P27P28-P30P31-P33P34-P35
L9954LXP Electrical specifications
Doc ID 16186 Rev 3 19/35
Figure 7. SPI - driver turn-on / off timing, minimum CSN HI time
Figure 8. SPI - timing of status bit 0 (fault condition)
C
S
N
dON
t
20
%
8
0
%
t
r
i
n
f
i
n
t
O
F
F
t
d
O
F
F
t
OFF
s
t
ate
O
N
s
t
a
t
e
O
F
F
s
t
a
t
e
ON
s
t
a
t
e
O
N
t
o
u
t
p
u
t
c
u
r
r
e
n
t
o
f
a d
r
iv
e
r
5
0
%
5
0
%
8
0
%
2
0
%
20
%
80
%
5
0
%
o
u
t
p
u
t
c
u
r
r
e
n
t
o
f
a d
r
iv
e
r
CSN
lo
w
t
o
h
igh
:
d
ata
f
r
o
m
s
h
i
f
t
registe
r
is
t
r
ansfe
r
r
e
d
t
o outpu
t
po
w
e
r
s
w
i
t
c
h
es
t
CSN_HI,min
output voltage
of a driver
output voltage
of a driver
CSN
CLK
DI
DO
CSN high to low and CLK stays low: status information of data bit 0 (fault condition) is transfered to DO
DI: data is not accepted
DO: status information of data bit 0 (fault condition) will stay as long as CSN is low
time
time
time
time
0
-
Application information L9954LXP
20/35 Doc ID 16186 Rev 3
3 Application information
3.1 Dual power supply: V
S
and V
CC
The power supply voltage V
S
supplies the half bridges and the high-side drivers. An internal
charge-pump is used to drive the high-side switches. The logic supply voltage V
CC
(stabilized 5 V) is used for the logic part and the SPI of the device.
Due to the independent logic supply voltage the control and status information not are lost, if
there are temporary spikes or glitches on the power supply voltage. In case of power-on
(V
CC
increases from under voltage to V
POR Off
= 4.2 V) the circuit is initialized by an
internally generated power-on-reset (POR). If the voltage V
CC
decreases under the
minimum threshold (V
POR ON
= 3.4 V), the outputs are switched to 3-state (high impedance)
and the status registers are cleared.
3.2 Standby mode
The standby mode of the L9954LXP is activated by clearing the bit 23 of the input data
register 0. All latched data is cleared and the inputs and outputs are switched to high
impedance. In the standby mode the current at V
S
(V
CC
) is less than 6 µA (50µA) for
CSN = high (DO in 3-state). By switching the V
CC
voltage a very low quiescent current can
be achieved. If bit 23 is set, the device is switched to active mode.
3.3 Inductive loads
Each half bridge is built by an internally connected high-side and a low-side power DMOS
transistor. Due to the built-in reverse diodes of the output transistors, inductive loads can be
driven at the outputs OUT1 to OUT3 without external free-wheeling diodes. The high-side
drivers OUT4 to OUT6 are intended to drive resistive loads. Hence only a limited energy
(E<1mJ) can be dissipated by the internal ESD-diodes in freewheeling condition. For
inductive loads (L>100μH) an external free-wheeling diode connected to GND and the
corresponding output is needed.
3.4 Diagnostic functions
All diagnostic functions (over/open-load, power supply over-/under voltage, temperature
warning and thermal shutdown) are internally filtered and the condition has to be valid for at
least 32 µs (open-load: 1ms, respectively) before the corresponding status bit in the status
registers is set. The filters are used to improve the noise immunity of the device. Open-load
and temperature warning function are intended for information purpose and not changes the
state of the output drivers. On contrary, the overload condition disables the corresponding
driver (over-current) and overtemperature switchs off all drivers (thermal shutdown). Without
setting the over-current recovery bits in the input data register, the microcontroller has to
clear the over-current status bits to reactivate the corresponding drivers.
L9954LXP Application information
Doc ID 16186 Rev 3 21/35
3.5 Overvoltage and under voltage detection
If the power supply voltage V
S
rises above the overvoltage threshold V
SOV Off
(typical 21 V),
the outputs OUT1 to OUT6 are switched to high impedance state to protect the load. When
the voltage V
S
drops below the under voltage threshold V
SUV Off
(UV-switch-off voltage), the
output stages are switched to the high impedance to avoid the operation of the power
devices without sufficient gate driving voltage (increased power dissipation). If the supply
voltage V
S
recovers (register 0: bit 20=0) to normal operating voltage the outputs stages
return to the programmed state after at least 32 µs.
If the under voltage/overvoltage recovery disable bit is set, the automatic turn-on of the
drivers is deactivated. The microcontroller needs to clear the status bits to reactivate the
drivers. It is strongly recommended to set bit 20 to avoid a possible high current oscillation in
case of a shorted output to GND and low battery voltage.
3.6 Charge pump
The charge pump runs under all conditions in normal mode. In standby the charge pump is
out of action.
3.7 Temperature warning and thermal shutdown
If junction temperature rises above T
j TW
a temperature warning flag is set after at least 32
µs and is detectable via the SPI. If junction temperature increases above the second
threshold T
j SD
, the thermal shutdown bit is set and power DMOS transistors of all output
stages are switched off to protect the device after at least 32 µs. Temperature warning flag
and thermal shutdown bit are latched and must be cleared by the microcontroller. The
related bit is only cleared if the temperature decreases below the trigger temperature. If the
thermal shutdown bit has been cleared the output stages are reactivated.
3.8 Open-load detection
The open-load detection monitors the load current in each activated output stage. If the load
current is below the open-load detection threshold for at least 1 ms (t
dOL
) the corresponding
open-load bit is set in the status register. Due to mechanical/electrical inertia of typical loads
a short activation of the outputs (e.g. 3 ms) can be used to test the open-load status without
changing the mechanical/electrical state of the loads.
3.9 Overload detection
In case of an over-current condition a flag is set in the status register in the same way as
open-load detection. If the over-current signal is valid for at least t
ISC
= 32 µs, the over-
current flag is set and the corresponding driver is switched off to reduce the power
dissipation and to protect the integrated circuit. If the over-current recovery bit of the output
is zero the microcontroller has to clear the status bits to reactivate the corresponding driver.
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24P25-P27P28-P30P31-P33P34-P35

L9954LXPTR

Mfr. #:
Buy L9954LXPTR
Manufacturer:
STMicroelectronics
Description:
Motor / Motion / Ignition Controllers & Drivers Door Actuator Driver 0.75A 1600mOhm
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet