LTC4260
1
4260fc
For more information www.linear.com/LTC4260
Typical applicaTion
FeaTures
DescripTion
Positive High Voltage
Hot Swap Controller with
I
2
C Compatible Monitoring
The LTC
?/DIV>
4260 Hot Swap" controller allows a board to be
safely inserted and removed from a live backplane. Using
an external N-channel pass transistor, the board supply
voltage can be ramped up at an adjustable rate. An I
2
C
interface and onboard ADC allow monitoring of board
current, voltage and fault status.
The device features adjustable analog foldback current
limit with latch off or automatic restart after the LTC4260
remains in current limit beyond an adjustable time-out
delay.
The controller has additional features to interrupt the host
when a fault has occurred, notify when output power is
good, detect insertion of a load card and power-up in
either the on or off state.
applicaTions
n
Allows Safe Board Insertion into Live Backplane
n
8-Bit ADC Monitors Current and Voltage
n
I
2
C"/SMBus Interface
n
Wide Operating Voltage Range: 8.5V to 80V
n
High Side Drive for External N-Channel MOSFET
n
Input Overvoltage/Undervoltage Protection
n
Optional Latchoff or Autoretry After Faults
n
Alerts Host After Faults
n
Foldback Current Limiting
n
Available in 24-Lead SO, 24-Lead Narrow
  SSOP and 32-Lead (5mm ?5mm) QFN Packages
n
Electronic Circuit Breakers
n
Live Board Insertion
n
Computers, Servers
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Power Up Waveforms
3A, 48V Card Resident Application
UV
BACKPLANE  PLUG-IN
CARD
2.67k
*
1.74k
49.9k
48V
SDA
SCL
ALERT
GND
V
DD
SENSE
LTC4260
INTV
CC
100k
FDB3632
0.010
10
6.8nF
C
L
43.5k
3.57k
V
OUT
48V
24k
68nF
*DIODES INC. SMBT70A
0.1礔
0.1礔
GATE
TIMER
GND
FB
BD_PRST
ADIN
GPIO
4260 TA01
SOURCE
OV
SDAO
SDAI
SCL
ALERT
ON
+
V
IN
50V/DIV
V
OUT
50V/DIV
GPIO
5V/DIV
25ms/DIV
4260 TA02
I
IN
2A/DIV
C
L
= 1000F