Datasheet

IN
GND
FAULT1
ILIM
EN1
R
ILIM
20 kΩ
R
FAULT
2x 100 kΩ
Input
TPS2561
0.1 Fμ
Power Pad
C
RETRY
2x 0.22 µF
FAULT2
EN2
VOUT1
VOUT2
2x C
LOAD
OUT1
OUT2
IN
GND
FAULT1
ILIM
EN1
R
ILIM
20 kΩ
R
FAULT
2x 100 kΩ
Input
TPS2561
0.1 Fμ
Power Pad
C
RETRY
2x 0.22 µF
FAULT2
EN2
External Logic
Signal & Drivers
VOUT1
VOUT2
2x C
LOAD
OUT1
OUT2
TPS2560
TPS2561
SLVS930A – DECEMBER 2009– REVISED FEBRUARY 2012 www.ti.com
AUTO-RETRY FUNCTIONALITY
Some applications require that an overcurrent condition disables the part momentarily during a fault condition
and re-enables after a pre-set time. This auto-retry functionality can be implemented with an external resistor and
capacitor. During a fault condition, FAULTx pulls ENx low disabling the part. The part is disabled when ENx is
pulled below the turn-off threshold, and FAULTx goes high impedance allowing C
RETRY
to begin charging. The
part re-enables when the voltage on ENx reaches the turn-on threshold, and the auto-retry time is determined by
the resistor/capacitor time constant. The part will continue to cycle in this manner until the fault condition is
removed.
Figure 19. Auto-Retry Functionality
Some applications require auto-retry functionality and the ability to enable/disable with an external logic signal.
The figure below shows how an external logic signal can drive EN through R
FAULT
and maintain auto-retry
functionality. The resistor/capacitor time constant determines the auto-retry time-out period.
Figure 20. Auto-Retry Functionality With External EN Signal
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