LTC1645 Datasheet, PDF (1/24 Pages) Linear Technology – Dual-Channel Hot Swap Controller/Power Sequencer

LTC1645
Dual-Channel Hot Swap
Controller/Power Sequencer
FEATURES
s _{Allows Safe Board Insertion and Removal from a}
Live Backplane
s _{Programmable Power Supply Sequencing}
s _{Programmable Electronic Circuit Breaker}
s _{User-Programmable Supply Voltage Power-Up and}
Power-Down Rate
s _{High Side Drivers for External N-Channel FETs}
s _{Controls Supply Voltages from 1.2V to 12V}
s _{Ensures Proper Power-Up Behavior}
s _{Undervoltage Lockout}
s _{Glitch Filter Protects Against Spurious RESET Signals}
U
APPLICATIO S
s _{Hot Board Insertion}
s _{Power Supply Sequencing}
s _{Electronic Circuit Breaker}
DESCRIPTIO
The LTC^®1645 is a 2-channel Hot Swap^TM controller that
allows a board to be safely inserted and removed from a
live backplane. Using external N-channel pass transistors,
the supply voltages can be ramped at a programmable
rate. Two high side switch drivers control the N-channel
gates for supply voltages ranging from 1.2V to 12V. The
two channels can be set to ramp up and down separately,
or they can be programmed to rise and fall simultaneously,
ensuring power supply tracking at the two outputs.
Programmable electronic circuit breakers protect against
shorts at either output. The RESET output can be used to
generate a system reset when a supply voltage falls below
a user-programmed voltage. An additional spare com-
parator is available for monitoring a second supply
voltage.
The LTC1645 is available in the 8- and 14-pin SO packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Hot Swap is a trademark of Linear Technology Corporation.
TYPICAL APPLICATIO
5V and 3.3V Hot Swap
0.005Ω* IRF7413
V_OUT2
V_IN2
3.3V
+
5A
C_LOAD2
ON
0.005Ω* IRF7413
V_IN1
V_OUT1
5V/DIV
5V
+
5A
10Ω
C_LOAD1
GATEn
10Ω
10V/DIV
0.01µF
25V
0.01µF
25V
7
6
12
3
SENSE1 GATE1
8
V_CC1
V_CC2 SENSE2 GATE2
LTC1645
ON
5
ON
(8-LEAD)
10k
GND
BACKPLANE PLUG-IN CARD
GND
4
1645 TA01
*LRF1206-01-R005-J (IRC)
V_OUT2
5V/DIV
V_OUT1
5V/DIV
5V and 3.3V Hot Swap Waveforms
1