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Rainbow Electronics MAX5929 User Manual

General description, Applications features, Pin configurations ordering information

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General Description

The MAX5927/MAX5929 +1V to +13.2V quad hot-swap
controllers provide complete protection for multisupply
systems. They allow the safe insertion and removal of cir-
cuit cards into live backplanes. These devices hot swap
multiple supplies ranging from +1V to +13.2V, provided
one supply is at or above +2.7V and only one supply is
above +11.0V. The input voltage rails (channels) can be
configured to sequentially turn-on/off, track each other,
or have completely independent operation.

The discharged filter capacitors of the circuit card pro-
vide low impedance to the live backplane. High inrush
currents from the backplane to the circuit card can burn
up connectors and components, or momentarily collapse
the backplane power supply leading to a system reset.
The MAX5927/MAX5929 hot-swap controllers prevent
such problems by gradually ramping up the output volt-
age and regulating the current to a preset limit when the
board is plugged in, allowing the system to stabilize
safely. After the startup cycle is complete, on-chip com-
parators provide VariableSpeed/BiLevel™ protection
against short-circuit and overcurrent faults, and provide
immunity against system noise and load transients. The
load is disconnected in the event of a fault condition. The
MAX5929A automatically restarts after a fault condition,
while the MAX5929L must be unlatched. The MAX5927
fault management mode is selectable.

The MAX5927/MAX5929 offer a variety of options to
reduce external component count and design time. All
devices integrate an on-board charge pump to drive
the gates of low-cost external N-channel MOSFETs, an
adjustable startup timer, and an adjustable current limit.
The devices offer integrated features like startup cur-
rent regulation and current glitch protection to eliminate
external timing resistors and capacitors. The
MAX5929_L provides an open-drain active-low status
output for each channel, the MAX5929_H provides an
open-drain active-high status output for each channel,
and the MAX5927 status output polarity is selectable.

The MAX5927 is available in a 32-pin thin QFN package
and the MAX5929 is available in a 24-pin QSOP pack-
age. All devices are specified over the extended tem-
perature range, -40°C to +85°C.

Applications

Features

Safe Hot Swap for +1V to +13.2V Power Supplies

with Any Input Voltage (V

IN_

2.7V and Only One

V

IN_

> 11.0V)

Adjustable Circuit Breaker/Current-Limit

Threshold from 25mV to 100mV

Configurable Tracking, Sequencing, or

Independent Operation Modes

VariableSpeed/BiLevel Circuit-Breaker Response
Internal Charge Pumps Generate N-Channel

MOSFET Gate Drives

Inrush Current Regulated at Startup
Autoretry or Latched Fault Management
Programmable Undervoltage Lockout
Status Outputs Indicate Fault/Safe Condition

MAX5927/MAX5929

Low-Voltage, Quad, Hot-Swap

Controllers/Power Sequencers

________________________________________________________________ Maxim Integrated Products

1

32

31

30

29

28

27

26

LIM1

ON1

ON2

POL

MODE

ON3

ON4

25

LIM2

9

10

11

12

13

14

15

STAT2

TIM

N.C.

LATCH

STAT3

STAT4

BIAS

16

GND

17

18

19

20

21

22

23

GATE3

SENSE3

IN3

N.C.

LIM3

GATE2

SENSE2

8

7

6

5

4

3

2

STAT1

GATE4

SENSE4

IN4

LIM4

GATE1

SENSE1

MAX5927

THIN QFN

1

IN1

24

IN2

TOP VIEW

Pin Configurations

Ordering Information

19-2945; Rev 0; 8/03

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.

EVALUATION KIT

AVAILABLE

PART

TEMP RANGE

PIN-PACKAGE

MAX5927ETJ

-40°C to +85°C

32 Thin QFN-EP**

MAX5929LHEEG*

-40°C to +85°C

24 QSOP

MAX5929LLEEG*

-40°C to +85°C

24 QSOP

MAX5929AHEEG*

-40°C to +85°C

24 QSOP

MAX5929ALEEG*

-40°C to +85°C

24 QSOP

VariableSpeed/BiLevel is a trademark of Maxim Integrated
Products, Inc.

PCI Express Hot Plug

Hot Plug-In Daughter Cards

RAID

Power-Supply
Sequencing/Tracking

Basestation Line Cards

Portable Computer Device
Bays (Docking Stations)

Network Switches, Routers,
Hubs

Selector Guide and Typical Operating Circuit appear at end
of data sheet.

*Future product—contact factory for availability.
**EP = Exposed paddle.

Pin Configurations continued at end of data sheet.