MAX5916EUI+ ,Dual PCI 2.2 Hot-Swap ControllersApplicationsMAX5915EUI* -40°C to +85°C 28 TSSOPPCI 2.2 ServerMAX5915UUI 0°C to +85°C 28 TSSOPPCI Se ..
MAX5917AESE+ ,+65V Simple Swapper Hot-Swap SwitchesFeaturesThe MAX5910/MAX5917 are fully integrated hot-swap♦ Provides Safe Hot Swap for +10V to +65V ..
MAX5917BESE+ ,+65V Simple Swapper Hot-Swap SwitchesELECTRICAL CHARACTERISTICS(V = +42V, GND = 0, UVLO = open circuit, V = +3.3V, and T = -40°C to +85° ..
MAX5918LEEE ,Low-Voltage, Dual Hot-Swap Controllers with Independent ON/OFF ControlFeaturesThe MAX5918 and MAX5919 are +1V to +13.2V dual Safe Hot Swap for +1V to +13.2V Power Suppl ..
MAX5918LEEE+ ,Low-Voltage, Dual Hot-Swap Controllers with Independent ON/OFF ControlMAX5918/MAX591919-2496; Rev 0; 7/02Low-Voltage, Dual Hot-Swap Controllers with Independent ON/OFF C ..
MAX5919AEEE ,Low-Voltage, Dual Hot-Swap Controllers with Independent ON/OFF ControlELECTRICAL CHARACTERISTICS(V = +1V to +13.2V provided at least one supply is higher than +2.7V, V = ..
MAZ8082-H ,Silicon planar typeFeatures•Extremely low noise voltage caused from the diode (2.4V to 39V,1/3 to 1/10 of our conventi ..
MAZ8082-L ,Silicon planar typeZener DiodesMAZ8000 SeriesSilicon planar typeUnit : mmFor stabilization of power supplyKA
MAZ8082-M ,Silicon planar typeElectrical characteristics within part numbers T = 25°CaTemperaturecoefficient ofZener voltage Rev ..
MAZ8091G ,Silicon planar typeelectrical characteristics WZ Zwithin part numbersReverse current I V Specified valuemAR R2*Tempera ..
MAZ8091-H ,Silicon planar typeElectrical Characteristics T = 25°CaParameter Symbol Conditions Min Typ Max UnitForward voltage V ..
MAZ8091-L ,Silicon planar typeelectrical characteristicsZ Zwithin part numbersReverse current I V ··············· Specified value ..
MAX5915EUI+-MAX5916AEUI+-MAX5916EUI+
Dual PCI 2.2 Hot-Swap Controllers
General DescriptionThe MAX5915/MAX5915A/MAX5916/MAX5916A dual
PCI 2.2 hot-swap controllers allow for safe insertion and
removal of two PCI cards into live PCI slots or back-
planes by limiting the inrush current at startup. After
startup, these devices provide protection against short-
circuit, overcurrent, and undervoltage conditions.
The MAX5915/MAX5915A/MAX5916/MAX5916Apro-
vide independent power controls for +3.3V, +5V, ±12V,
and +3.3V auxiliary supplies of two PCI cards. These
devices provide intelligent selective thermal shutdown
control that shuts down the channel with an overcurrent
fault. All devices include internal power MOSFETs for the
+12V, -12V, and +3.3V auxiliary outputs. These devices
use internal charge pumps to activate the gates of the
internal FETs controlling the +3.3V auxiliary supply.
Internal FETs and current-sense circuitry regulate the±12V and the +3.3V auxiliary supplies. Channels A and B
operate independently, allowing a single device to moni-
tor two PCI card slots.
The MAX5915/MAX5915A offer latched fault protection
and the MAX5916/MAX5916A offer autorestart fault pro-
tection. The devices are available in the low-profile
28-pin TSSOP package.
FeaturesPCI 2.2 CompliantIndependent Power Controls for +3.3V, +5V, ±12V,
and +3.3V Auxiliary Supplies of Two PCI CardsInternal MOSFET Switches for ±12V and +3.3V
Auxiliary OutputsSeparate ON/OFF Control Input for Each ChannelIndependent +3.3V Auxiliary Output ON/OFF
ControlOvercurrent Foldback with Timeout and Shutdown
Protection for ±12V and +3.3V Auxiliary Rails with
Status ReportBrick Wall with Timeout and Shutdown Protection
for +5V and +3.3V Rails with Status ReportOutput Undervoltage Monitoring for +3.3V, +5V,
+12V, and +3.3V Auxiliary Rails with Status Report+3.3V Auxiliary AutorestartIntelligent Selective Thermal Shutdown Control
Shuts Down Only the Channel with an Overcurrent
Fault28-Pin TSSOP Package
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers19-2420; Rev 2; 9/05
Ordering Information
ApplicationsPCI 2.2 Server
PCI Server
RAID
PARTTEMP RANGEPIN-PACKAGE
MAX5915EUI*-40°C to +85°C28 TSSOP
MAX5915UUI0°C to +85°C28 TSSOP
MAX5915AEUI*-40°C to +85°C28 TSSOP
MAX5915AUUI0°C to +85°C28 TSSOP
MAX5916EUI*-40°C to +85°C28 TSSOP
MAX5916UUI0°C to +85°C28 TSSOP
MAX5916AEUI*-40°C to +85°C28 TSSOP
MAX5916AUUI0°C to +85°C28 TSSOP
Selector Guide, Pin Configuration, Functional Diagram, and
Typical Operating Circuit appear at end of data sheet.
Typical Application Circuit+12VIN
+3.3V
+5V
-12VIN
3.3VGATE_3.3VSEN_3.3VO_5VGATE_5VSEN_
FAIRCHILD
FDS6670A
FAIRCHILD
FDS6670A
0.005Ω
0.005Ω
10kΩ
10kΩ
5VO_
470μF
47μF
3.3VAUXIN3.3VAUXO_
PGOOD_GND
ON_ON
OFF
AUXON_
+12VO_
-12VO_
MAX5915
MAX5915A
MAX5916
MAX5916A
470μF
4.7μF⎥⎥ 0.1μF
OFF
4.7μF⎥⎥ 0.1μF
4.7μF⎥⎥ 0.1μF
47μF
47μF
-12V
+12V
+3.3VAUX
*Contact factory for availabilty.
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
ABSOLUTE MAXIMUM RATINGSStresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
+12VIN to GND...................................................-0.3V to +14.0V
-12VIN to GND........................................................-14V to +0.3V
-12VO_ to GND......................................+0.3V to (V-12VIN- 0.3V)
+12VO_, 3.3VGATE_, 5VGATE_
to GND..................................................-0.3V to (V+12VIN+ 0.3V)
Any Other Pin to GND...........................................-0.3V to +6.0V
Continuous Power Dissipation (TA= +70°C)
28-Pin TSSOP (derate 23.8mW/°C above +70°C)...........1.9W
Operating Temperature Ranges:
MAX591_U_ _......................................................0°C to +85°C
MAX591_A U_ _...................................................0°C to +85°C
MAX591_E_ _....................................................-40°C to +85°C
MAX591_ AE_ _................................................-40°C to +85°C
Maximum Junction Temperature.....................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
ELECTRICAL CHARACTERISTICS(V-12VIN= -12V, V+12VIN= +12V, V3.3VAUXIN= +3.3V, VON_= VAUXON_= +5V, TA= TMINto TMAX, unless otherwise specified.
Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
POWER SUPPLIESMain Supply Input Voltage
RangeV+12VIN10.81213.2V
Main Supply Undervoltage
Lockout (UVLO)V+12UVLOV+12VIN rising9.61010.8V
Main Supply UVLO HysteresisVUVLO, HYS100mV
Main Input UVLO Delay TimetDEG, UVLOFigures 1 and 2 (Note 1)1.6ms
Supply CurrentIQ2.55.0mA
+3.3V SUPPLY CONTROLGate Charge CurrentI3.3VGATE_, CHGV 3 .3 V GAT E _ = + 6V , V 3 .3 V S E N _ = + 3.3V ,3 .3 V O_ = + 3.3V 51530µA
Gate Discharge CurrentI3.3VGATE_, DISV3.3VGATE _ = +12V, VON_ = 0V50150250µA
Gate High VoltageV3.3VGATE_, HIGHI3.3VGATE _ = 1µAV+12VIN -
0.5V+12VINV
Gate Low VoltageV3.3VGATE_, LOWI3.3VGATE _ = 1µA, VON_ = 0V0.10.4V
3.3VO_ Input Bias CurrentI3.3VO_, BIASV3.3VO_ = +3.3V20µA
3.3VO_ Internal PulldownRPDVON_ = 0V1kΩ
3.3VSEN_ Input Bias CurrentI3.3VSEN_, BIASV3.3VSEN_ = +3.3V10µA
Current-Limit ThresholdV3.3V, LIMV3.3VGATE _ = +6V414651mV
Output Undervoltage ThresholdV3.3VIN, UVV3.3VGATE _ falling2.792.892.99V
Output Undervoltage Threshold
Hysteresis30mV
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
ELECTRICAL CHARACTERISTICS (continued)(V-12VIN= -12V, V+12VIN= +12V, V3.3VAUXIN= +3.3V, VON_= VAUXON_= +5V, TA= TMINto TMAX, unless otherwise specified.
Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
+5V SUPPLY CONTROLGate Charge CurrentI5VGATE_, CHGV5VGATE_ = +6V, V5VSEN_ = +5V,
V5VO_ = +5V51530µA
Gate Discharge CurrentI5VGATE_, DISV5VGATE_ = +12V, VON_ = 0V50150250µA
Gate High VoltageV5VGATE_, HIGHI5VGATE_ = 1µAV+12VIN -
0.5VV+12VINV
Gate Low VoltageV5VGATE_, LOWI5VGATE_ = 1µA, VON_ = 0V0.10.4V
5VO_ Input Bias CurrentI5VO_, BIASV5VO_ = +5V20µA
5VO_ Internal PulldownR5VO_, PDVON_ = 0V1kΩ
5VSEN_ Input Bias CurrentI5VSEN_, BIASV5VSEN_ = +5V10µA
Current-Limit ThresholdV5VO_, LIMV5VGATE_ falling273135mV
Output Undervoltage ThresholdV5VO_, UVOutput falling4.344.504.70V
Output Undervoltage Threshold
Hysteresis45mV
+12V SUPPLY CONTROLTA = +25°C, ID = 0.5A0.320.38On-Resistance of Internal SwitchRDS(ON), +12VTA = +85°C, ID = 0.5A0.5Ω
Foldback Current LimitI+12VIN, LIMV+12VO_ = 0V0.6811.36A
Current-Foldback ThresholdOutput current rising (Note 2)1.4A
Output Undervoltage ThresholdV+12VO_, UVOutput falling10.0010.410.82V
+12VO_ Internal PulldownR+12VO_, PDVON_ = 0V1kΩ
-12V SUPPLY CONTROLTA = +25°C, ID = 0.1A0.580.9On-Resistance of Internal SwitchRDS(ON), -12VTA = +85°C, ID = 0.1A1.3Ω
Foldback Current LimitI-12VIN, LIMV-12VO_ = 0V136205273mA
Current-Foldback ThresholdOutput current rising (Note 2)240mA
-12VO_ Internal PullupR-12VO_, PUVON_ = 0V1kΩ
+3.3VAUX SUPPLY CONTROLInput Voltage RangeV3.3VAUXIN3.03.33.6V
3.3VAUXIN Undervoltage
LockoutVUVLO, AUXInput rising2.652.752.85V
HysteresisVUVLO-AUX, HYS30mV
Supply CurrentIQ, 3.3VAUX12mA
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
ELECTRICAL CHARACTERISTICS (continued)(V-12VIN= -12V, V+12VIN= +12V, V3.3VAUXIN= +3.3V, VON_= VAUXON_= +5V, TA= TMINto TMAX, unless otherwise specified.
Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSTA = +25°C, ID = 0.4A0.240.4On-Resistance of Internal SwitchRDS(ON), 3.3VAUXTA = +85°C, ID = 0.4A0.6Ω
Foldback Current LimitI3.3VAUXIN, LIMV3.3VAUXO_ = 0V0.50.751.0A
Current-Foldback ThresholdOutput current rising (Note 2)1.2A
Output Undervoltage ThresholdV3.3VAUXIN, UV2.762.892.99V
Auxiliary Input UVLO Delay TimetDEG, UVLO(Note 1)1.6ms
3.3VAUXO_ Internal PulldownR3.3VAUXO_ON_ = 0V1kΩ
ON AND AUXON COMPARATORSThreshold Voltage1.02.1V
HysteresisVHYS25mV
Input Bias CurrentIB, COMP20µA
ON_ and AUXON_ Deglitch
TimetDEGFigures 5–8 (Note 3)4µs
FAULT RESPONSE, PGOOD_ STATUS OUTPUT COMPARATORStRESPFigures 5–8MAX5915/MAX59160.51.5msPGOOD_ Output Overcurrent
and Undervoltage Response
TimetRESP2Figures 5–8MAX5915A/MAX5916A100ns
Output Overcurrent and
Undervoltage Deglitch TimetDELAYFigures 3–716 x
tRESPms
PGOOD_ Startup TimeouttSTARTSee Figures 1, 2, 5, 6, 7, and 84 x
tDELAYms
Autorestart DelaytRESTARTDelay time to restart after OC and/or
UV shutdown
64 x
tSTARTms
PGOOD_ Output Low VoltageVOLISINK = 2mA, ON_ = 0V0.50.7V
PGOOD_ Output High Leakage
CurrentILEAKVPGOOD_ = +5.5V1µA
Thermal Shutdown ThresholdTSD(Note 4)125°C
Thermal Shutdown HysteresisTHYS5°C
Full Thermal Shutdown
ThresholdTSD, FULL(Note 5)TSD +°C
Full Thermal Shutdown
HysteresisTHYS, FULL5°C
Note 1:tDEG, UVLOis negative edge triggered. There is no time delay when the inputs rise above the UVLO threshold.
Note 2:The current threshold when the output current starts to fold back. See the Typical Operating Characteristics.
Note 3:tDEGis negative edge triggered. ON_ or AUXON_ transition from low to high has no delay.
Note 4:Temperature threshold at which the outputs of the channel with overcurrent shut down.
Note 5:The temperature threshold at which both channels shut down.
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
Typical Operating Characteristics(V+12VIN= +12V, V3.3VAUXIN= +3.3V, V-12VIN= -12V, V5V= +5V, V3.3V= +3.3V, R5VSEN_= 0.005Ω, R3.3VSEN_ = 0.005Ω, C3.3VO_ =
MAX5915 toc09
OUTPUT CURRENT (A)
3.3VAUX_ VOLTAGE (V)
3.3VAUX_ VOLTAGE
vs. OUTPUT CURRENT
3.3VO_ SENSE RESISTOR VOLTAGE
vs. DIFFERENTIAL SWITCH VOLTAGE
MAX5915 toc08
VIN - V3.3VSEN_ (V)
3.3VO_ CURRENT-LIMIT THRESHOLD (mV)
DURING CURRENT LIMIT
FAIRCHILD
FDS6670A
3.3VO_ VOLTAGE
vs. OUTPUT CURRENTMAX5915 toc07
3.3VO_ VOLTAGE (V)
FAIRCHILD
FDS6670A
5VO_ SENSE RESISTOR VOLTAGE
vs. DIFFERENTIAL SWITCH VOLTAGE
MAX5915 toc06
VIN - V5VSEN_ (V)
5VO_ CURRENT-LIMIT THRESHOLD (mV)
DURING CURRENT LIMIT
FAIRCHILD
FDS6670A
5VO_ VOLTAGE
vs. OUTPUT CURRENTMAX5915 toc05
OUTPUT CURRENT (A)
5VO_ VOLTAGE (V)
FAIRCHILD
FDS6670A
-12VO_ CURRENT FOLDBACK
vs. DIFFERENTIAL SWITCH VOLTAGEMAX5915 toc04
V-12VIN - V-12VO_ (V)
-12VO_ CURRENT FOLDBACK (mA)
-12VO_ VOLTAGE
vs. OUTPUT CURRENT
MAX5915 toc03
OUTPUT CURRENT (mA)
-12VO_ VOLTAGE (V)
+12VO_ CURRENT FOLDBACK
vs. DIFFERENTIAL SWITCH VOLTAGE
MAX5915 toc02
V+12VIN - V+12VO_ (V)
+12VO_ CURRENT FOLDBACK (A)
+12VO_ VOLTAGE
vs. OUTPUT CURRENT
MAX5915 toc01
OUTPUT CURRENT (A)
+12VO_ VOLTAGE (V)
11.41.5
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
Typical Operating Characteristics (continued)(V+12VIN= +12V, V3.3VAUXIN= +3.3V, V-12VIN= -12V, V5V= +5V, V3.3V= +3.3V, R5VSEN_= 0.005Ω, R3.3VSEN_ = 0.005Ω, C3.3VO_ =
2ms/div
TIME-TO-CHARGE GATE
(CGATE = 10nF)ON_
5V/div
3.3VGATE_
5V/div
MAX5915 toc18
5VGATE_
5V/div
200μs/div
TIME-TO-CHARGE GATE
(CGATE = 1nF)ON_
5V/div
3.3VGATE_
5V/div
MAX5915 toc17
5VGATE_
5V/div
100μs/div
TIME-TO-CHARGE GATE
(CGATE = 0.1nF)ON_
5V/div
3.3VGATE_
5V/div
MAX5915 toc16
5VGATE_
5V/div
MAX5915 toc15
TEMPERATURE (°C)
-12V INTERNAL SWITCH R
(35-1510
-12V INTERNAL SWITCH RON
vs. TEMPERATURE
MAX5915 toc14
TEMPERATURE (°C)
3.3V AUXILIARY INTERNAL SWITCH R
(3510-15
3.3V AUXILIARY INTERNAL SWITCH RON
vs. TEMPERATURE
MAX5915 toc13
TEMPERATURE (°C)
+12V INTERNAL SWITCH R
(3510-15
+12V INTERNAL SWITCH RON
vs. TEMPERATURE
5VGATE_ AND 3.3VGATE_
DISCHARGE CURRENT vs. TEMPERATURE
MAX5915 toc12
TEMPERATURE (°C)
GATE DISCHARGE CURRENT (3510-15
3.3VGATE_
CGATE = 1nF
5VGATE_
5VGATE_ AND 3.3VGATE_
CHARGE CURRENT vs. TEMPERATUREMAX5915 toc11
TEMPERATURE (°C)
GATE CHARGE CURRENT (3510-15
3.3VGATE_
CGATE = 1nF
5VGATE_
3.3VAUX_ CURRENT FOLDBACK
vs. DIFFERENTIAL SWITCH VOLTAGEMAX5915 toc10
V3.3VAUXIN - V3.3VAUXO_ (V)
3.3VAUX_ CURRENT FOLDBACK (mA)
5001.02.02.53.01.53.5
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
Typical Operating Characteristics (continued)(V+12VIN= +12V, V3.3VAUXIN= +3.3V, V-12VIN= -12V, V5V= +5V, V3.3V= +3.3V, R5VSEN_= 0.005Ω, R3.3VSEN_ = 0.005Ω, C3.3VO_ =
MAX5915 toc27
TEMPERATURE (°C)
+12V INPUT UVLO THRESHOLD (V)3510-15
+12V INPUT UVLO
THRESHOLD vs. TEMPERATURE
3.3V AUXILIARY INPUT UVLO
THRESHOLD vs. TEMPERATURE
MAX5915 toc26
3.3V AUXILIARY INPUT UVLO THRESHOLD (V)35-1510
3.3V AUXILIARY OUTPUT UNDERVOLTAGE
THRESHOLD vs. TEMPERATURE
MAX5915 toc25
TEMPERATURE (°C)
3.3V AUXILIARY OUTPUT UNDERVOLTAGE THRESHOLD (V)603510-15
3.3V OUTPUT UNDERVOLTAGE
THRESHOLD vs. TEMPERATURE
MAX5915 toc24
TEMPERATURE (°C)
3.3V OUTPUT UNDERVOLTAGE THRESHOLD (V)35-1510
5V OUTPUT UNDERVOLTAGE
THRESHOLD vs. TEMPERATURE
MAX5915 toc23
TEMPERATURE (°C)
5V OUTPUT UNDERVOLTAGE THRESHOLD (V)3510-15
+12V OUTPUT UNDERVOLTAGE
THRESHOLD vs. TEMPERATURE
MAX5915 toc22
TEMPERATURE (°C)
+12V OUTPUT UNDERVOLTAGE THRESHOLD (V)3510-15
ON_ AND AUXON_ THRESHOLD
vs. TEMPERATURE
MAX5915 toc21
TEMPERATURE (°C)
ON_ AND AUXON_ THRESHOLD (V)3510-15
RISING
FALLING
3.3VAUXIN SUPPLY CURRENT
vs. TEMPERATURE
MAX5915 toc20
TEMPERATURE (°C)
3.3VAUXIN SUPPLY CURRENT (mA)3510-15
+12VIN SUPPLY CURRENT
vs. TEMPERATURE
MAX5915 toc19
TEMPERATURE (°C)
+12VIN SUPPLY CURRENT (mA)3510-15
-4085
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
Typical Operating Characteristics (continued)(V+12VIN= +12V, V3.3VAUXIN= +3.3V, V-12VIN= -12V, V5V= +5V, V3.3V= +3.3V, R5VSEN_= 0.005Ω, R3.3VSEN_ = 0.005Ω, C3.3VO_ =
40ms/div
MAIN SUPPLY
TURN-OFF WAVEFORMSON_
5V/div
+12VO_
10V/div
MAX5915 toc36
PGOOD_
5V/div
5VO_
5V/div
200μs/div
TURN-ON DELAY+12VIN
10V/div
3.3VAUXIN_
2V/div
MAX5915 toc35
3.3VAUXO_
2V/div
+12VO_
10V/div
ON_ = 5V
AUXON_ = 5V
10ms/div
AUXILIARY SUPPLY
TURN-ON WAVEFORMSAUXON_
5V/div
3.3VAUXO_
2V/div
MAX5915 toc34
PGOOD_
5V/divON_ = 5.0V
10ms/div
MAIN SUPPLY
TURN-ON WAVEFORMSON_
5V/div
12VO_
10V/div
MAX5915 toc33
PGOOD_
5V/div
5VO_
5V/div
AUXON_ = 5V
5VO_ SENSE RESISTOR VOLTAGE
vs. TEMPERATUREMAX5915 toc32
TEMPERATURE (°C)
5V0_ SENSE RESISTOR VOLTAGE (mV)35-1510
DURING CURRENT
LIMIT
3.3V AUXILIARY CURRENT
FOLDBACK vs. TEMPERATUREMAX5915 toc31
TEMPERATURE (°C)
3.3V AXILIARY CURRENT FOLDBACK (mA)35-1510
3.3VO_ SENSE RESISTOR VOLTAGE
vs. TEMPERATURE
MAX5915 toc30
TEMPERATURE (°C)
3.3V SENSE RESISTOR VOLTAGE (mV)3510-15
DURING CURRENT LIMIT
-12V OUTPUT CURRENT
FOLDBACK vs. TEMPERATUREMAX5915 toc29
TEMPERATURE (°C)
-12V OUTPUT CURRENT FOLDBACK (mA)35-1510
MAX5915 toc28
TEMPERATURE (°C)
+12V OUTPUT CURRENT FOLDBACK (A)3510-15
+12V OUTPUT CURRENT
FOLDBACK vs. TEMPERATURE
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
Typical Operating Characteristics (continued)(V+12VIN= +12V, V3.3VAUXIN= +3.3V, V-12VIN= -12V, V5V= +5V, V3.3V= +3.3V, R5VSEN_= 0.005Ω, R3.3VSEN_ = 0.005Ω, C3.3VO_ =
-12VO_ CURRENT FOLDBACKMAX5915 toc45
2ms/div
I-12VO_
500mA/div
PGOOD_
5V/div
-12VO_
5V/div
-12VO_ IMMEDIATE
SHORT-CIRCUIT RESPONSEMAX5915 toc44
200ns/div
I-12VO_
2A/div
PGOOD_
5V/div
-12VO_
5V/div
+12VO_ CURRENT FOLDBACKMAX5915 toc43
2ms/div
I+12VO_
5A/div
PGOOD_
5V/div
+12VO_
5V/div
+12VO_ IMMEDIATE
SHORT-CIRCUIT RESPONSEMAX5915 toc42
1μs/div
I+12VO_
10A/div
PGOOD_
5V/div
+12VO_
5V/div
AUXILIARY SUPPLY
FAULT MANAGEMENTMAX5915 toc41
400ms/div
5VO_
+12VO_
5V/div
3.3VAUXO_
5V/div
PGOOD_
5V/div
400ms/div
MAIN SUPPLY
AUTORESTART FAULT MANAGEMENT+12VO_
5V/div
5VO_
2V/div
MAX5915 toc40
3.3VAUXO_
5V/div
PGOOD_
5V/div
2ms/div
MAIN SUPPLY
LATCHED FAULT MANAGEMENT+12VO_
5V/div
5VO_
2V/div
MAX5915 toc39
3.3VAUXO_
5V/div
PGOOD_
5V/div
2μs/div
tDEG DELAY TIMEON_
5V/div
3.3VAUXO_
2V/div
MAX5915 toc38
PGOOD_
5V/div
20ms/div
AUXILIARY SUPPLY
TURN-OFF WAVEFORMSON_
5V/div
3.3VAUXO_
2V/div
MAX5915 toc37
PGOOD_
5V/div
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
Typical Operating Characteristics (continued)(V+12VIN= +12V, V3.3VAUXIN= +3.3V, V-12VIN= -12V, V5V= +5V, V3.3V= +3.3V, R5VSEN_= 0.005Ω, R3.3VSEN_ = 0.005Ω, C3.3VO_ =
3.3VAUXO_ CURRENT FOLDBACKMAX5915 toc51
2ms/div
I3.3VAUXO_
1A/div
PGOOD_
5V/div
3.3VAUXO_
2V/div
3.3VAUXO_ IMMEDIATE
SHORT-CIRCUIT RESPONSEMAX5915 toc50
2μs/div
I3.3VAUXO_
10A/div
PGOOD_
5V/div
3.3VAUXO_
2V/div
3.3VO_ CURRENT LIMITMAX5915 toc49
2ms/div
I3.3VO_
10A/div
PGOOD_
5V/div
3.3VO_
2V/div
3.3VO_ IMMEDIATE
SHORT-CIRCUIT RESPONSEMAX5915 toc48
20μs/div
I3.3VO_
10A/div
PGOOD_
5V/div
3.3VO_
2V/div
FAIRCHILD
FDS6670A
5VO_ CURRENT LIMITMAX5915 toc47
2ms/div
I5VO_
10A/div
PGOOD_
5V/div
5VO_
5V/div
5VO_ IMMEDIATE
SHORT-CIRCUIT RESPONSEMAX5915 toc46
40μs/div
I5VO_
10A/div
PGOOD_
5V/div
5VO_
5V/div
FAIRCHILD
FDS6670A
MAX5915A/MAX5916A
3.3VAUXO_ SHORT CIRCUITMAX5915 toc54
100ns/div
PGOOD_
5V/div
3.3VAUXO_
1V/div
tRESP2
MAX5915A/MAX5916A
3.3VO_ SHORT CIRCUITMAX5915 toc53
100ns/div
PGOOD_
5V/div
3.3VO_
1V/div
tRESP2
MAX5915A/MAX5916A
12VO_ SHORT CIRCUITMAX5915 toc52
100ns/div
PGOOD_
5V/div
12VO_
5V/div
tRESP2
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap Controllers
PINNAMEFUNCTION+12VOAChannel A +12V Output3.3VGATEAChannel A +3.3V External N-Channel MOSFET Gate Drive. 3.3VGATEA driven by +12VIN.3.3VSENAChannel A External 3.3V Current-Sense Input3.3VOAChannel A +3.3V Output SenseONAChannel A Master ON/OFF Output Control. Drive ONA logic high to enable channel A +3.3V, +5V, and
±12V outputs. V+12VIN must be > UVLO threshold.ONBChannel B Master ON/OFF Output Control. Drive ONB logic high to enable channel B +3.3V, +5V, and
±12V outputs. V+12VIN must be > UVLO threshold.GNDGroundPGOODAChannel A Power-Good Output. PGOODA is an open-drain output that pulls low when a fault is detected on
channel A outputs.PGOODBChannel B Power-Good Output. PGOODB is an open-drain output that pulls low when a fault is detected on
channel B outputs.AUXONAChannel A 3.3VAUX ON/OFF Control Input. Drive AUXONA logic high to enable channel A +3.3V auxiliary
output.AUXONBChannel B 3.3VAUX ON/OFF Control Input. Drive AUXONB logic high to enable channel B +3.3V auxiliary
output.3.3VAUXOAChannel A 3.3VAUX Output3.3VAUXIN3.3VAUX Input. Provides power to the +3.3V auxiliary channels.3.3VAUXOBChannel B 3.3VAUX Output-12VOBChannel B -12V Output-12VIN-12V Input-12VOAChannel A -12V Output5VOBChannel B +5V Output Sense5VSENBChannel B External +5V Current-Sense Input5VGATEBChannel B +5V External N-Channel MOSFET Gate Drive. 5VGATEB driven by +12VIN.5VOAChannel A +5V Output Sense5VSENAChannel A External +5V Current-Sense Input5VGATEAChannel A +5V External N-Channel MOSFET Gate Drive. 5VGATEA driven by +12VIN.3.3VOBChannel B +3.3V Output Sense3.3VSENBChannel B External +3.3V Current-Sense Input3.3VGATEBChannel B +3.3V External N-Channel MOSFET Gate Drive. 3.3VGATEB driven by +12VIN.+12VOBChannel B +12V Output+12VIN+12V Input. +12VIN powers the main supplies of the MAX5915/MAX5915A/MAX5916/MAX5916A.
Pin Description
MAX5915/MAX5915A/MAX5916/MAX5916A
Detailed DescriptionThe MAX5915/MAX5915A/MAX5916/MAX5916A are cir-
cuit-breaker ICs for hot-swap applications where a PCI
card is inserted into a slot that is connected to a live
backplane. Normally, when a card is plugged into a live
backplane, the card’s discharged capacitors provide a
low-impedance path that can momentarily cause the
main power supply to collapse. Both devices provide
startup current limiting and undervoltage/overcurrent
monitoring of two separate PCI card slots. Current limit-
ing and short-circuit protection are achieved using
external n-channel MOSFETs on the +3.3V and +5V
supply lines and internal MOSFETs on the ±12V and
+3.3V auxiliary supply lines.
External sense resistors monitor the output currents of
the +3.3V and +5V supplies. These external sense
resistors adjust the overcurrent trip threshold. PCI stan-
dards dictate maximum values for the supply power
and total power drawn from the backplane. The maxi-
mum power that any one PCI board can draw is 25W.
Table 1 lists PCI standard maximum voltage, current,
and power for each supply.
Table 1 illustrates that both the +5V and +3.3V supplies
can draw up to 25W. Total combination of output power
should be limited to 25W based on PCI standard.
Startup ModeThe +12V input powers the internal circuitry of these
devices. The main supply outputs (3.3VO_, 5VO_,
+12VO_, and -12VO_) can become active only after
both of the following events have occurred:
•V+12VINis above its undervoltage lockout (UVLO)
threshold.ON_ is driven high.
Figure 1 displays typical startup waveforms. The main
supplies can be enabled without using the auxiliary
auxiliary supply is not used.
The auxiliary supply (3.3VAUXO_) is available after both
of these events have occurred:
•V3.3VAUXINis above its UVLO threshold.AUXON_ is driven high.
Normal Operation +3.3V, +5V,±12V Outputs
The internal circuitry for these devices monitors the out-
put voltage on all channels except the -12V supply. All
outputs are monitored for overcurrent. An undervoltage
condition occurs when any supply’s output voltage falls
below the set undervoltage level. An overcurrent fault
occurs when a monitored output current reaches the
set overcurrent threshold. Each supply has its own
overcurrent and undervoltage thresholds. If any of the
monitored voltages fall below their respective under-
voltage level, or if any of the monitored output currents
reach their overcurrent threshold, for a time period,
tDELAY, the controller disables the channel with the fault
condition (see the Fault Managementsection).
External sense resistors monitor current through the
external MOSFETs of the +3.3V and +5V outputs, while
the current for the ±12V supplies are internally monitored.
A fault condition on one of the main outputs causes all
the channel’s main outputs to shut down after tDELAY
and then either latch off (MAX5915/MAX5915A) or auto-
matically restart after tRESTART(MAX5916/MAX5916A).
A fault on any of the channel’s main outputs does not
affect the channel’s auxiliary outputs.
Normal Operation +3.3V Auxiliary OutputAuxiliary output voltage and current are monitored inter-
nally. The +3.3V auxiliary output is independentof the
main outputs but the main outputs are dependenton
the auxiliary outputs. Fault conditions on the main out-
puts do not affect the auxiliary. A fault on the auxiliary
Dual PCI 2.2 Hot-Swap Controllers
Table 1. PCI Standard Maximum Values
SUPPLY VOLTAGE (V)*VOLTAGE TOLERANCE (%)MAX CURRENT (A)MAX POWER (W)±5525
+3.3±0.3V7.625
+12±50.56
-12±100.11.2
+3.3 aux (enabled)±100.3751.24
+3.3 aux (disabled)±100.020.066
*Supply voltage is referenced to the output of the MAX5915/MAX5916.
channel outputs, auxiliary and main. A fault condition
occurs when the output voltage falls below the set
undervoltage threshold or the output current reaches the
overcurrent threshold. When a fault occurs, all supplies
of the affected channel are disabled after a time period
tDELAY. All outputs are automatically restarted after a
time equal to tRESTART. This reset is built into all devices.
Current LimitsAll supplies are protected against output overcurrent or
short-circuit conditions. The MAX5915/MAX5915A and
MAX5916/MAX5916A employ a “brickwall” current limit
on the +3.3V and +5V supplies and a current-foldback
scheme on the ±12V and +3.3V auxiliary supplies.
BrickwallA brickwall current limit protects the +3.3V and +5V
main supplies by limiting the load current. The external
sense resistors and the current-limit threshold set the
brickwall current limits. A fault occurs when the load
current reaches the brickwall limit. The main outputs
shut down after tDELAYif the fault remains. The brick-
wall feature limits inrush current caused by positive
supply voltage steps.
FoldbackThe ±12V and +3.3V auxiliary supplies employ an
internal current-foldback scheme. The MAX5915/
MAX5915A/MAX5916/MAX5916A gradually limit the load
current once the current-foldback threshold is reached. If
the overcurrent condition lasts longer than a fast tran-
sient, the output current is reduced to the foldback cur-
rent limit and remains at that level for tDELAYunless the
overcurrent condition is cleared. See the Typical
Operating Characteristics.
MAX5915/MAX5915A/MAX5916/MAX5916A
Dual PCI 2.2 Hot-Swap ControllerstSTART
ON_
+12VIN
3.3VAUXIN
PGOOD_
TIMING NOT TO SCALE
AUXON_
+12V
UVLO THRESHOLD
3.3VAUX UVLO THRESHOLD
+12VO_
5VO_
3.3VO_
3.3VAUXO_
-12VO_
Figure 1. Startup Waveforms
