LTC1647-3_15 Datasheet, PDF (1/22 Pages) Linear Technology – Dual Hot Swap Controllers

LTC1647-1/
LTC1647-2/LTC1647-3
Dual Hot Swap Controllers
FEATURES
n _{Allows Safe Board Insertion and Removal from a}
Live Backplane
n _{Programmable Electronic Circuit Breaker}
n _{FAULT Output Indication}
n _{Programmable Supply Voltage Power-Up Rate}
n _{High Side Drive for External MOSFET Switches}
n _{Controls Supply Voltages from 2.7V to 16.5V}
n _{Undervoltage Lockout}
APPLICATIONS
n _{Hot Board Insertion}
n _{Electronic Circuit Breaker}
n _{Portable Computer Device Bays}
n _{Hot Plug Disk Drive}
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
DESCRIPTION
The LTC^®1647-1/LTC1647-2/LTC1647-3 are dual Hot
Swap™ controllers that permit a board to be safely inserted
and removed from a live backplane.
Using external N-channel MOSFETs, the board supply
voltages can be ramped up at a programmable rate. A high
side switch driver controls the MOSFET gates for supply
voltages ranging from 2.7V to 16.5V. A programmable
electronic circuit breaker protects against overloads and
shorts. The ON pins are used to control board power or
clear a fault.
The LTC1647-1 is a dual Hot Swap controller with a
common V_CC pin, separate ON pins and is available in an
SO-8 package. The LTC1647-2 is similar to the LTC1647-1
but combines a fault status flag with automatic retry at
the ON pins and is also available in the SO-8 package. The
LTC1647-3 has individual V_CC pins, ON pins and FAULT
status pins for each channel and is available in a 16-lead
narrow SSOP package.
TYPICAL APPLICATION
Dual Motherboard Resident Hot Swap Controller
12V
SUPPLY
20mΩ
IRF7413
10Ω
+
C_LOAD
V_OUT1
(2.5A)
V_CC SENSE 1 GATE 1
ON1 ON1 _LTC1647-1
ON2 ON2
GND SENSE 2 GATE 2
10Ω
20mΩ
IRF7413
*REQUIRED FOR V_CC > 10V
10nF
DDZ23*
10nF
DDZ23*
+
C_LOAD
V_OUT2
(2.5A)
1647-1/2/3 TA01
ON/OFF Sequence
V_ON
5V/DIV
V_GATE
10V/DIV
V_OUT
5V/DIV
10ms/DIV
1647-1/2/3 TA01a
1647fa
1