LM5068 Datasheet, PDF (1/1 Pages) National Semiconductor (TI) – NEGATIVE VOLTAGE HOT SWAP CONTROLLER

LM5068
Negative Voltage Hot-Swap Controller
PRELIMINARY
General Description
Features
The LM5068 hot-swap controller provides intelligent con-
trol of power supply connections during the insertion and
removal of circuit cards powered by live system backplanes
The LM5068 provides both in-rush current control and
short-circuit protection functions, and limits power supply
transients in the backplane caused by the insertion of
additional circuit cards. The LM5068 controls the external
N-Channel MOSFET to provide programmable load current
limiting and circuit breaker functions using a single external
current sense resistor. The LM5068 issues a power good
(PWRGD) signal at the conclusion of a successful power-
on sequence. Input over-voltage or under-voltage fault
conditions will cancel the PWRGD indication.
The LM5068-1 and -2 indicate power good as an open-
drain active high PWRGD state. The LM5068-3 and -4
indicate power-good as an open-drain active low PWRGD
state. The LM5068-1 and -3 latch off after a fault condition
is detected while the LM5068-2 and -4 continuously re-try
at intervals set by a programmable timer.
• In-rush current limiting for safe board insertion into
live backplanes
• Fast response to over-current fault conditions with
active current limiting
• Wide -10V to -100V input voltage range
• Programmable Under-voltage and Over-voltage
shutdown protection with adjustable hysteresis
• Programmable Multi-Function Timer for board
insertion de-bounce delay
• Fault timer avoids nuisance trips caused by short
duration load transients
• Active gate clamping during initial power application
• Available in both latched fault and automatic retry
versions
• Available with either active HIGH or active LOW
power good flag
The LM5068 is available in MSOP-8 package.
Samples are available now; volume production is expected
in late January 2004.
For additional information, contact Don Ashley at
[e-mail]
© 2003 National Semiconductor Corporation