UCC39151 Datasheet, PDF (1/6 Pages) Texas Instruments – 15V Programmable Hot Swap Power Manager

UCC39151
15V Programmable Hot Swap Power Manager
FEATURES
• Integrated 0.15Ω Power MOSFET
• 7V to 15V Operation
• Digital Programmable Current Limit
from 0A to 3A
• Programmable ON Time
• Programmable Start Delay
• Fixed 2% Duty Cycle
• Thermal Shutdown
• Fault Output Indicator
• Maximum Output Current can be set
to 1A above the Programmed Fault
Level or to a full 4A
• Power SOIC and TSSOP, Low
Thermal Resistance Packaging
BLOCK DIAGRAM
DESCRIPTION
The UCC39151 Programmable Hot Swap Power Manager provides com-
plete power management, hot swap capability, and circuit breaker func-
tions. The only external component required to operate the device, other
than power supply bypassing, is the fault timing capacitor, C_T. All control
and housekeeping functions are integrated, and externally programmable.
These include the fault current level, maximum output sourcing current,
maximum fault time, and startup delay. In the event of a constant fault, the
Internal fixed 2% duty cycle ratio limits average output power.
The internal 4 bit DAC allows programming of the fault level current from
0A to 3A with 0.25A resolution. The IMAX control pin sets the maximum
sourcing current to 1A above the trip level or to a full 4A of output current
for fast output capacitor charging.
When the output current is below the fault level, the output MOSFET is
switched ON with a nominal ON resistance of 0.15Ω. When the output cur-
rent exceeds the fault level, but is less than the maximum sourcing level,
the output remains switched ON, but the fault timer starts, charging CT.
Once CT charges to a preset threshold, the switch is turned OFF, and re-
mains OFF for 50 times the programmed fault time. When the output cur-
rent reaches the maximum sourcing level, the MOSFET transitions from a
switch to a constant current source.
(continued)
Note: Pin numbers refer to DIL-16 and SOIC-16 packages.
02/99
UDG-94136-3