Datasheet

AC Electrical Characteristics
Limits are for T
J
= 25˚C and V
IN
= 5.0V.
Symbol Parameter Conditions Min Typ Max Units
t
r
OUT
x
Rise Time (Note 5) C
L
= 33 µF, I
LOAD
= 500 mA 1.5 ms
t
f
OUT
x
Fall Time (Note 6) C
L
= 33 µF, I
LOAD
= 500 mA 0.9 ms
t
ON
Turn-on Delay (Note 7) C
L
= 33 µF, I
LOAD
= 500 mA 2.9 ms
t
OFF
Turn-off Delay (Note 8) C
L
= 33 µF, I
LOAD
= 500 mA 0.7 ms
t
F
Flag Delay (Note 9) I
FLAG
=10mA 7 ms
Note 5: Time for OUT
x
to rise from 10% to 90% of its enabled steady-state value after EN
x
(EN
x
) is asserted.
Note 6: Time for OUT
x
to fall from 10% to 90% of its enabled steady-state value after EN
x
(EN
x
) is deasserted.
Note 7: Time between EN
x
rising through V
IH
(EN
x
falling through V
IL
) and OUT
x
rising through 90% of its enabled steady-state voltage.
Note 8: Time between EN
x
falling through V
IL
(EN
x
rising through V
IH
) and OUT
x
falling through 10% of its enabled steady-state voltage.
Note 9: Time between EN
x
rising through V
IN
(EN
x
falling through V
IN
) and FLAG
X
falling through 0.3V when OUT
X
is connected to GND.
Pin Description
Pin Number Pin Name Pin Function
2, 6 IN 1, 2 Supply Inputs: These pins are the inputs to the power switches and the supply
input for the IC. In most applications they are connected together externally
and to a single input voltage supply.
1, 5 GND 1, 2 Grounds: Must be connected together and to a common ground.
15, 14, 11, 10 OUT 1, 2, 3, 4 Switch Outputs: These pins are the outputs of the high side switches.
3, 4, 7, 8 LM3544-H: EN 1, 2, 3, 4
(LM3544-L: EN 1, 2, 3, 4)
Enable (Inputs): Active-high (or active-low) logic enable inputs.
16, 13, 12, 9 FLAG 1, 2, 3, 4 Fault Flag (Outputs): Active-low open drain outputs. Indicates over-current,
UVLO or thermal shutdown. See "Application Information" section for more
details.
LM3544
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