General Description

The MAX5959/MAX5960 quad hot-plug controllers are

devices provide hot-plug control for the main 12V, 3.3V,

and 3.3V auxiliary supplies of four PCIe slots. The

MAX5959/MAX5960’s logic inputs/outputs allow interfac-

ing directly with the system hot-plug management con-

troller or through an SMBus™ with an external I/O

expander such as the MAX7313. An integrated

debounced attention switch and present-detect signals

simplify system design.

The MAX5959/MAX5960 drive eight external n-channel

MOSFETs to control the 12V and 3.3V main outputs. The

3.3V auxiliary outputs are controlled through 0.2Ω n-chan-

nel MOSFETs. Internal charge pumps provide the gate

drive for the 12V outputs while the gate drive of the 3.3V

output is driven by the 12V input supply clamped to 5.5V

above the respective 3.3V main supply rail. The 3.3V aux-

iliary outputs are completely independent from the main

outputs with their own charge pumps.

At power-up, the MAX5959/MAX5960 keep all of the

MOSFETs off until the supplies rise above their respective

undervoltage lockout (UVLO) thresholds. Upon a turn-on

command, the MAX5959/MAX5960 enhance the external

and internal MOSFETs slowly with a constant gate current

to limit the power-supply inrush current.

The MAX5959/MAX5960 actively limit the current to pro-

tect all outputs at all times and shutdown if an overcurrent

condition persists longer than the programmable overcur-

rent timeout. After an overcurrent or overtemperature fault

condition, the MAX5959L/MAX5960L latch off while the

MAX5959A/MAX5960A automatically restart after a restart

time delay. The MAX5959/MAX5960 are offered in latch-

off or auto-restart versions (see the

Selector Guide).

The MAX5959/MAX5960 are available in an 80-pin TQFP

package and operate over the -40°C to +85°C tempera-

ture range.

Applications

Servers

Desktop Mobile Server Platforms

Workstations

Features

o PCIe Compliant

o Hot Swap 12V, 3.3V, and 3.3V Auxiliary for 4

PCIe Slots

o Integrated Power MOSFETs for Auxiliary Supply

Rails

o Controls dI/dt and dV/dt

o Active Current-Limiting Protects Against

Overcurrent/Short-Circuit Conditions

o Programmable Current-Limit Timeout

o PWRGD Signal Outputs with Programmable

Power-On Reset (POR) (160ms Default)

o Latched FAULT Signal Output after Overcurrent

or Overtemperature Fault

o Attention Switch Inputs/Outputs with 4ms

Debounce

o Present-Detect Inputs

o Force-On Inputs Facilitate Testing/Debug

o Thermal Shutdown

o Allow Control through SMBus with an I/O

Expander

Quad PCI Express, Hot-Plug Controllers

________________________________________________________________

Maxim Integrated Products

1

PART

TEMP RANGE

PIN-

PACKAGE

PKG

CODE

MAX5959AECS+

-40°C to +85°C

80 TQFP

C80-1

MAX5959LECS+

-40°C to +85°C

80 TQFP

C80-1

MAX5960AECS+

-40°C to +85°C

80 TQFP

C80-1

MAX5960LECS+

-40°C to +85°C

80 TQFP

C80-1

PART

LATCH OFF

AUTO RESTART

GUARANTEED AUX CURRENT (mA)

MAX5959AECS+

√

375

MAX5959LECS+

√

375

MAX5960AECS+

√

550

MAX5960LECS+

√

550

Selector Guide

Ordering Information

19-XXXX; Rev 0; 7/07

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

+

Denotes lead-free package.

Pin Configuration and Typical Application Circuit appear at

end of data sheet.

PCI-Express is a registered trademark of PCI-SIG Corp. SMBus is a trademark of Intel Corp.