LTC4260 Datasheet, PDF (1/28 Pages) Linear Technology – Positive High Voltage Hot Swap Controller with I2C Compatible Monitoring

FEATURES
■ _{Allows Safe Insertion into Live Backplane}
■ _{8-Bit ADC Monitors Current and Voltage}
■ _I²_C^TM_{/SMBus Interface}
■ _{Wide Operating Voltage Range: 8.5V to 80V}
■ _{High Side Drive for External N-Channel MOSFET}
■ _{Input Overvoltage/Undervoltage Protection}
■ _{Optional Latchoff or Autoretry After Faults}
■ _{Alerts Host After Faults}
■ _{Foldback Current Limiting}
■ _{Available in 24-Lead SO, 24-Lead Narrow}
SSOP and 32-Lead (5mm × 5mm) QFN Packages
U
APPLICATIO S
■ _{Electronic Circuit Breakers}
■ _{Live Board Insertion}
■ _{Computers, Servers}
LTC4260
Positive High Voltage
Hot Swap Controller with
I²C Compatible Monitoring
DESCRIPTIO
The LTC^®4260 Hot Swap^TM 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 I²C
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.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Hot Swap is a trademark of Linear Technology Corporation.
I²C is a trademark of Philips Electronics N.V.
TYPICAL APPLICATIO
48V
SDA
SCL
ALERT
GND
BACKPLANE PLUG-IN
CARD
*DIODES INC. SMBT70A
3A, 48V Card Resident Application
49.9k
0.1µF
1.74k
0.010Ω _FDB3632
10Ω _100k
6.8nF
+
C_L
UV V_DD SENSE GATE
SOURCE
*
2.67k _OV
FB
SDAO
SDAI
SCL
ALERT
LTC4260
BD_PRST
ADIN
ON _INTVCC
TIMER
GND ^GPIO
4260 TA01
0.1µF
68nF
V_OUT
48V
43.5k
3.57k
24k
Power Up Waveforms
C_L = 1000µF
V_IN
50V/DIV
I_IN
2A/DIV
V_OUT
50V/DIV
GPIO
5V/DIV
25ms/DIV
4260 TA02
4260f
1