Document
19-2945; Rev 0; 8/03
KIT ATION EVALU LE B A IL A AV
Low-Voltage, Quad, Hot-Swap Controllers/Power Sequencers
General Description Features
o Safe Hot Swap for +1V to +13.2V Power Supplies with Any Input Voltage (VIN_ ≥ 2.7V and Only One VIN_ > 11.0V) o Adjustable Circuit Breaker/Current-Limit Threshold from 25mV to 100mV o Configurable Tracking, Sequencing, or Independent Operation Modes o VariableSpeed/BiLevel Circuit-Breaker Response o Internal Charge Pumps Generate N-Channel MOSFET Gate Drives o Inrush Current Regulated at Startup o Autoretry or Latched Fault Management o Programmable Undervoltage Lockout o Status Outputs Indicate Fault/Safe Condition
MAX5927/MAX5929
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 circuit 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 provide 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 voltage 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 comparators 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 current 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 package. All devices are specified over the extended temperature range, -40°C to +85°C.
Ordering Information
PART MAX5927ETJ MAX5929LHEEG* MAX5929LLEEG* MAX5929AHEEG* MAX5929ALEEG* TEMP RANGE -40°C to +85°C -40°C to +85°C -40°C to +85°C -40°C to +85°C -40°C to +85°C PIN-PACKAGE 32 Thin QFN-EP** 24 QSOP 24 QSOP 24 QSOP 24 QSOP
*Future product—contact factory for availability. **EP = Exposed paddle. Selector Guide and Typical Operating Circuit appear at end of data sheet.
Pin Configurations
LIM1 MODE ON1
ON2 ON3
TOP VIEW
ON4
POL
32
31
30
29
28
27
26
25 24 23 22 21
LIM2
IN1 SENSE1 GATE1 LIM4 IN4 SENSE4 GATE4 STAT1
1 2 3 4 5 6 7 8 10 11 12 13 14 15 16
IN2 SENSE2 GATE2 LIM3 N.C. IN3 SENSE3 GATE3
MAX5927
20 19 18 17
Applications
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
STAT2
9
LATCH
STAT3
TIM
THIN QFN
VariableSpeed/BiLevel is a trademark of Maxim Integrated Products, Inc.
Pin Configurations continued at end of data sheet. 1
________________________________________________________________ Maxim Integrated Products
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.
STAT4
BIAS
GND
N.C.
Low-Voltage, Quad, Hot-Swap Controllers/Power Sequencers MAX5927/MAX5929
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND, unless otherwise noted.) IN_ ..........................................................................-0.3V to +14V GATE_.............................................................-0.3V to (IN_ + 6V) BIAS (Note 1) .............................................. (VIN - 0.3V) to +14V ON_, STAT_, LIM_ (MAX5927), TIM, MODE, LATCH (MAX5927), POL (MAX5927) (Note 1) .....................................................-0.3V to (VIN + 0.3V) SENSE_........................................................-0.3V to (IN_ + 0.3V) Current into Any Pin..........................................................±50mA Note 1: VIN is the largest of VIN1, VIN2, VIN3, and VIN4.
Stresses bey.