19-3473; Rev 0; 10/04
-48V Hot-Swap Controllers
with External R
SENSE
General Description
Features
The MAX5948A/MAX5948B are hot-swap controllers
that allow a circuit card to be safely hot plugged into a
live backplane. The MAX5948A/MAX5948B operate
from -20V to -80V and are well-suited for -48V power
systems. The MAX5948A is pin- and function-compati-
ble with both the LT1640AL and LT1640L. The
MAX5948B is pin- and function-compatible with both
the LT1640AH and LT1640H.
♦ Allow Safe Board Insertion and Removal from a
Live -48V Backplane
♦ Pin- and Function-Compatible with
LT1640AL/LT1640L (MAX5948A)
♦ Pin- and Function-Compatible with
LT1640AH/LT1640H (MAX5948B)
♦ Withstand -100V Input Transients with No
The MAX5948A/MAX5948B provide a controlled turn-on
to circuit cards preventing glitches on the power-supply
rail and damage to board connectors and components.
The MAX5948A/MAX5948B provide undervoltage, over-
voltage, and overcurrent protection. These devices
ensure the input voltage is stable and within tolerance
before applying power to the load.
External Components
♦ Operate from -20V to -80V
♦ Programmable Inrush and Short-Circuit Current
Limits
♦ Programmable Overvoltage Protection
♦ Programmable Undervoltage Lockout
♦ Power Up into a Shorted Load
Both the MAX5948A and MAX5948B protect a system
against overcurrent and short-circuit conditions by turning
off the external MOSFET in the event of a fault condition.
Both devices feature an open-drain power-good status
output, PWRGD for MAX5948A or PWRGD for
MAX5948B, that can be used to enable downstream
converters.
♦ Power-Good Control Output
Ordering Information
The MAX5948A/MAX5948B are available in an 8-pin SO
package. Both devices are specified for the extended
-40°C to +85°C temperature range.
PART
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
8 SO
MAX5948AESA
MAX5948BESA
8 SO
Applications
Selector Guide
Central-Office Switching
Network Switches/Routers
Server Line Cards
PART
PWRGD POLARITY
Active Low (PWRGD)
Active High (PWRGD)
MAX5948AESA
Base-Station Line Cards
MAX5948BESA
Pin Configuration
TOP VIEW
PWRGD
(PWRGD)
1
2
3
4
8
7
6
5
V
DD
OV
UV
DRAIN
GATE
MAX5948A
MAX5948B
V
SENSE
EE
SO
( ) FOR MAX5948B.
Typical Operating Circuit appears at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.