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SLUS374C − JULY 1999 − REVISED NOVEMBER 2005
1
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FEATURES
D
Precision Fault Threshold
D Charge Pump for Low R
DS(on
) High Side
Drive
D Differential Sense Inputs
D Programmable Average Power Limiting
D Programmable Linear Current Control
D Programmable Fault Time
D Fault Output Indicator
D Manual and Automatic Reset Modes
D Shutdown Control With Programmable
Softstart
D Undervoltage Lockout
D Electronic Circuit Breaker Function
DESCRIPTION
The UCC3919 family of hot swap power
managers provide complete power management,
hot swap, and fault handling capability. The
UCC3919 features a duty ratio current limiting
technique, which provides peak load capability
while limiting the average power dissipation of the
external pass transistor during fault conditions.
The UCC3919 has two reset modes, selected with
the TTL/CMOS compatible L/R pin. In one mode,
when a fault occurs the IC repeatedly tries to reset
itself at a user defined rate, with user defined
maximum output current and pass transistor
power dissipation. In the other mode the output
latches off and stays off until either the L/R pin is
reset or the shutdown pin is toggled. The on board
charge pump circuit provides the necessary gate
voltage for an external N-channel power FET.
TYPICAL APPLICATION DIAGRAM
UDG−01068
+
VDD
GND
LINEAR
CURRENT AMP
TIMER
CT
CAP
RS
IBIAS
IMAX
CSN GATE
FROM
SUPPLY
3 V TO 8 V
TO LOAD
CSP
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Copyright 2001 − 2005, Texas Instruments Incorporated
