MAX5920AESA+ Fast Delivery |IC PHOENIX CO.,LIMITED

MAX5920AESA+ ,-48V Hot-Swap Controller with External RSENSEFeaturesThe MAX5920A/MAX5920B are hot-swap controllers that♦ Allows Safe Board Insertion and Remova ..
MAX5920BESA ,-48V Hot-Swap Controller with External RSENSEFeaturesThe MAX5920A/MAX5920B are hot-swap controllers that Allows Safe Board Insertion and Remova ..
MAX5921AESA+T ,-48V Hot-Swap Controllers with External RSENSE and High Gate Pulldown CurrentELECTRICAL CHARACTERISTICS(V = 0V, V = 48V, T = -40°C to +85°C, unless otherwise noted. Typical val ..
MAX5921BESA ,-48V Hot-Swap Controllers with External RSENSE and High Gate Pulldown CurrentApplicationsMAX5921AESA -40°C to +85°C 8 SOTelecom Line CardsMAX5921BESA -40°C to +85°C 8 SONetwork ..
MAX5921BESA+ ,-48V Hot-Swap Controllers with External RSENSE and High Gate Pulldown Currentfeatures over these devices.and Current SpikesThe MAX5921/MAX5939 provide a controlled turn-on to♦ ..
MAX5921BESA+ ,-48V Hot-Swap Controllers with External RSENSE and High Gate Pulldown CurrentFeaturesThe MAX5921/MAX5939 hot-swap controllers allow a cir-♦ Allows Safe Board Insertion and Remo ..
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 ..
MAZ8091M ,Silicon planar typeFeatures•Extremely low noise voltage caused from the diode (2.4V to 39V,1/3 to 1/10 of our conventi ..
MAZ8091-M ,Silicon planar typeelectrical characteristicsZ Zwithin part numbersReverse current I V ··············· Specified value ..
MAZ8100-H ,Silicon planar typeZener DiodesMAZ8000 SeriesSilicon planar typeUnit : mmFor stabilization of power supplyKA
MAZ8100-L ,Silicon planar typeElectrical characteristics within part numbers T = 25°CaTemperaturecoefficient ofZener voltage Rev ..

MAX5920AESA+
-48V Hot-Swap Controller with External RSENSE
General Description
The MAX5920A/MAX5920B are hot-swap controllers that
allow a circuit card to be safely hot plugged into a live
backplane. The MAX5920A/MAX5920B operate from
-20V to -80V and are well-suited for -48V power systems.
These devices are pin and function compatible with the
LT4250 and pin compatible with the LT1640.
The MAX5920A/MAX5920B provide a controlled turn-on
to circuit cards preventing glitches on the power-supply
rail and damage to board connectors and components.
The MAX5920A/MAX5920B provide undervoltage, over-
voltage, and overcurrent protection. These devices
ensure the input voltage is stable and within tolerance
before applying power to the load.
Both the MAX5920A and MAX5920B protect a system
against overcurrent and short-circuit conditions by turn-
ing off the external MOSFET in the event of a fault con-
dition. The MAX5920A/MAX5920B also provide
protection against input voltage steps. During an input
voltage step, the MAX5920A/MAX5920B limit the cur-
rent drawn by the load to a safe level without turning off
power to the load.
Both devices feature an open-drain power-good status
output (PWRGDfor the MAX5920A or PWRGD for the
MAX5920B) that can be used to enable downstream
converters. A built-in thermal-shutdown feature is also
included to protect the external MOSFET in case of
overheating.
The MAX5920A/MAX5920B are available in an 8-pin SO
package. Both devices are specified for the extended
-40°C to +85°C temperature range.
Applications
Telecom Line Cards
Network Switches/Routers
Central-Office Line Cards
Server Line Cards
Base-Station Line Cards
FeaturesAllows Safe Board Insertion and Removal
from a Live -48V BackplanePin- and Function-Compatible with LT4250L
(MAX5920A)Pin-Compatible with LT1640L (MAX5920A)Pin- and Function-Compatible with LT4250H
(MAX5920B)Pin-Compatible with LT1640H (MAX5920B)Circuit-Breaker Immunity to Input Voltage Steps
and Current SpikesWithstands -100V Input Transients with No
External ComponentsProgrammable Inrush and Short-Circuit Current
LimitsOperates from -20V to -80VProgrammable Overvoltage ProtectionProgrammable Undervoltage LockoutPowers Up into a Shorted LoadPower-Good Control OutputThermal Shutdown Protects External MOSFET
MAX5920
-48V Hot-Swap Controller
with External RSENSE
GATE
SENSEVEE
VDD
DRAINOV
PWRGD
(PWRGD)
TOP VIEW
MAX5920A
MAX5920B
( ) FOR MAX5920B.
Pin Configuration
Ordering Information
19-2931; Rev 0; 8/03
PARTTEMP RANGEPIN-PACKAGE
MAX5920AESA-40°C to +85°C8 SO
MAX5920BESA-40°C to +85°C8 SO
Typical Operating Circuit and Selector Guide appear at end
of data sheet.
MAX5920
-48V Hot-Swap Controller
with External RSENSE
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VEE= 0V, VDD= 48V, TA= -40°C to +85°C. Typical values are at TA= +25°C, unless otherwise noted.) (Notes 1, 4)
Stresses 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.
All Voltages are Referenced to VEE, Unless Otherwise Noted.
Supply Voltage (VDD- VEE).................................-0.3V to +100V
DRAIN, PWRGD, PWRGD....................................-0.3V to +100V
PWRGD to DRAIN .............................................… -0.3V to +95V
PWRGD to VDD........................................................-95V to +85V
SENSE (Internally Clamped).................................-0.3V to +1.0V
GATE (Internally Clamped)....................................-0.3V to +18V
UV and OV..............................................................-0.3V to +60V
Current Through SENSE...................................................±40mA
Current into GATE...........................................................±300mA
Current into Any Other Pin................................................±20mA
Continuous Power Dissipation (TA= +70°C)
8-Pin SO (derate 5.9mW/°C above +70°C)..................471mW
Operating Temperature Range...........................-40°C to +85°C
Junction Temperature .....................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
POWER SUPPLIES
Operating Input Voltage RangeVDD2080V
Supply CurrentIDD(Note 2)0.72mA
GATE DRIVER AND CLAMPING CIRCUITS
Gate Pin Pullup CurrentIPUGATE drive on, VGATE = VEE-30-45-60µA
Gate Pin Pulldown CurrentIPDGATE drive off , VGATE = 2V245070mA
External Gate DriveΔVGATEVGATE - VEE, 20V ≤ VDD ≤ 80V1013.518V
GATE to VEE Clamp VoltageVGSCLMPVGATE - VEE, IGS = 30mA1516.418V
CIRCUIT BREAKER
Current-Limit Trip VoltageVCLVCL = VSENSE - VEE405060mV
SENSE Input Bias CurrentVSENSE = 50mV-1-0.20µA
UNDERVOLTAGE LOCKOUT
Internal Undervoltage Lockout
Voltage HighVUVLOHVDD increasing13.815.417.0V
Internal Undervoltage Lockout
Voltage LowVUVLOLVDD decreasing11.813.415.0V
UV PIN
UV High ThresholdVUVHUV voltage increasing1.2401.2551.270V
UV Low ThresholdVUVLUV voltage decreasing1.1051.1251.145V
UV HysteresisVUVHY_130mV
UV Input Bias CurrentIINUV-0.50µA
OV PIN
OV High ThresholdVOVHOV voltage increasing1.2351.2551.275V
OV Low ThresholdVOVLOV voltage decreasing1.1891.2051.221V
OV Voltage Reference HysteresisVOVHY50mV
OV Input Bias CurrentIINOVVOV = VEE-0.50µA
PWRGD OUTPUT SIGNAL REFERENCED TO DRAIN
DRAIN Input Bias CurrentIDRAINVDRAIN = 48V1080250µA
MAX5920
-48V Hot-Swap Controller
with External RSENSE
ELECTRICAL CHARACTERISTICS (continued)
(VEE= 0V, VDD= 48V, TA= -40°C to +85°C. Typical values are at TA= +25°C, unless otherwise noted.) (Notes 1, 4)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSRAIN Thr eshol d for P ow er - G ood VDLVDRAIN - VEE threshold for power-good
condition, DRAIN decreasing1.11.72.0V
GATE High ThresholdVGHΔVGATE - VGATE threshold for power-good
condition, ΔVGATE - VGATE decreasing1.01.62.0V
PWRGD, PWRGD Output
LeakageIOHPWRGD (MAX5920A) = 80V, VDRAIN = 48V,
PWRGD (MAX5920B) = 80V, VDRAIN = 0V10µA
PWRGD Output Low VoltageVOLVPWRGD - VEE; VDRAIN - VEE < VDL,
ISINK = 5mA (MAX5920A)0.110.4V
PWRGD Output Low VoltageVOLVPWRGD - VDRAIN; VDRAIN = 5V,
ISINK = 5mA (MAX5920B)0.110.4V
OVERTEMPERATURE PROTECTION
Overtemperature ThresholdTOTJunction temperature, temperature rising135°C
Overtemperature HysteresisTHYS20°C
AC PARAMETERS
OV High to GATE LowtPHLOVFigures 1a, 20.5µs
UV Low to GATE LowtPHLUVFigures 1a, 30.4µs
OV Low to GATE HightPLHOVFigures 1a, 23.3µs
UV High to GATE HightPLHVLFigures 1a, 33.4µs
SENSE High to GATE LowtPHLSENSEFigures 1a, 4a13µs
Current Limit to GATE LowtPHLCLFigures 1b, 4b350500650µs
MAX5920A, Figures 1a, 5a1.8DRAIN Low to PWRGD Low
DRAIN Low to (PWRGD - DRAIN)
High
tPHLDL
MAX5920B, Figures 1a, 5a3.4
MAX5920A, Figures 1a, 5b1.6GATE High to PWRGD Low
GATE High to (PWRGD-DRAIN)
High
tPHLGH
MAX5920B, Figures 1a, 5b2.5
TURN-OFF
Latch-Off PeriodtOFF(Note 3)128 x
tPHLCLms
Note 1:All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to VEE,
unless otherwise specified.
Note 2:Current into VDDwith UV = 3V, OV, DRAIN, PWRGD, SENSE = VEE, GATE = floating.
Note 3:Minimum duration of GATE pulldown following a circuit-breaker fault. The circuit breaker can be reset during this time by
toggling UV low, but the GATE pulldown does not release until tOFFhas elapsed.
Note 4:Limits are 100% tested at TA= +25°C and +85°C. Limits at -40°C are guaranteed by design.
MAX5920
-48V Hot-Swap Controller
with External RSENSE
Typical Operating Characteristics
(VDD= 48V, VEE= 0V, TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX5920 toc01
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (604020
TA = +85°CTA = +25°C
TA = -40°C
GATE VOLTAGE vs. SUPPLY VOLTAGE
MAX5920 toc02
SUPPLY VOLTAGE (V)
GATE VOLTAGE (V)602040100
TA = +25°C
CURRENT-LIMIT TRIP VOLTAGE
vs. TEMPERATURE
MAX5920 toc03
TEMPERATURE (°C)
TRIP VOLTAGE (mV)3510-15
GATE PULLUP CURRENT
vs. TEMPERATURE
MAX5920 toc04
TEMPERATURE (°C)
GATE PULLUP CURRENT (3510-15
VGATE = 0V
GATE PULLDOWN CURRENT
vs. TEMPERATURE
MAX5920 toc05
TEMPERATURE (°C)
GATE PULLDOWN CURRENT (mA)3510-15
VGATE = 2V
GATE PULLDOWN CURRENT
vs. OVERDRIVE
MAX5920 toc06
OVERDRIVE (mV)
GATE PULLDOWN CURRENT (mA)
VGATE = 2V
MAX5920
PWRGD OUTPUT LOW VOLTAGE
vs. TEMPERATURE (MAX5920A)
MAX5920 toc07
TEMPERATURE (°C)
PWRGD OUTPUT LOW VOLTAGE (mV)3510-15
IOUT = 1mA
PWRGD OUTPUT LEAKAGE CURRENT
vs. TEMPERATURE (MAX5920B)
MAX5920 toc08
TEMPERATURE (°C)
PWRGD OUTPUT LEAKAGE CURRENT (nA)3510-15
VDRAIN - VEE > 2.4V
MAX5920
-48V Hot-Swap Controller
with External RSENSE
5kΩ
VOV
VUV
VSENSE
VDRAIN
48V
MAX5920A
MAX5920B
PWRGD/PWRGD
VEE
VDD
DRAIN
GATE
SENSE
Figure 1a. Test Circuit 1
VUV
48V
MAX5920A
MAX5920B
PWRGD/PWRGD
VEE
VDD
DRAIN
GATE
SENSE
IRF53020V
10kΩ
10Ω
0.1μF
10Ω
Figure 1b. Test Circuit 2
MAX5920
-48V Hot-Swap Controller
with External RSENSE
Timing Diagrams
1.255V
tPHLOV0V
1.205V
tPLHOV
GATE
Figure 2. OV to GATE Timing
tPHLUV
1.125V1V
1.255V
tPLHUV
GATE
Figure 3. UV to GATE Timing
60mV
100mV
GATE
SENSE
VEE
tPHLSENSE
Figure 4a. SENSE to GATE Timing
tPHLCL1V
GATE
Figure 4b. Active Current-Limit Threshold
MAX5920
-48V Hot-Swap Controller
with External RSENSE
Timing Diagrams (continued)
DRAIN
PWRGD
VPWRGD - VDRAIN = 0V
PWRGD
DRAIN
VEE
VEE
VEE
tPHLDL
1.4V
1.4V
tPHLDL
Figure 5a. DRAIN to PWRGD/PWRGD Timing
ΔVGATE - VGATE = 0V
GATE
PWRGD
VEE
VEE
VGATE - VGATE = 0V
GATE
PWRGD
VPWRGD - VDRAIN = 0V
1.4V
1.4V
tPHLGH
tPHLGH
Figure 5b. GATE to PWRGD/PWRGD Timing
LOGIC
GATE
DRIVER
UVLOVCC AND
REFERENCE
GENERATOR
REF
VCC
REF
VDL
VEE
VGH
ΔVGATE
50mV
VDD
VEESENSEGATEDRAIN
PWRGD
PWRGD
MAX5920A
MAX5920B
OUTPUT DRIVE
Block Diagram
MAX5920
Detailed Description
The MAX5920A/MAX5920B are integrated hot-swap
controllers for -48V power systems. They allow circuit
boards to be safely hot plugged into a live backplane
without causing a glitch on the power-supply rail. When
circuit boards are inserted into a live backplane, the
bypass capacitors at the input of the board’s power
module or switching power supply can draw large
inrush currents as they charge. The inrush currents can
cause glitches on the system power-supply rail and
damage components on the board.
The MAX5920A/MAX5920B provide a controlled turn-on
to circuit cards preventing glitches on the power-supply
rail and damage to board connectors and components.
Both the MAX5920A and MAX5920B provide undervolt-
age, overvoltage, and overcurrent protection. The
MAX5920A/MAX5920B ensure the input voltage is sta-
ble and within tolerance before applying power to the
load. The devices also provide protection against input
voltage steps. During an input voltage step, the
MAX5920A/MAX5920B limit the current drawn by the
load to a safe level without turning off power to the load.
-48V Hot-Swap Controller
with External RSENSE
Pin Description
PIN
MAX5920AMAX5920BNAMEFUNCTION—PWRGD
Power-Good Signal Output. PWRGD is an active-low open-drain status output referenced
to VEE. PWRGD is latched low when VDRAIN - VEE ≤ VDL and VGATE > (ΔVGATE - VGH),
indicating a power-good condition. PWRGD is open drain otherwise.1PWRGD
Power-Good Signal Output. PWRGD is an active-high open-drain status output referenced
to DRAIN. PWRGD latches in a high-impedance state when VDRAIN - VEE ≤ VDL and
VGATE > (ΔVGATE - VGH), indicating a power-good condition. PWRGD is pulled low to
DRAIN otherwise.OV
Input Pin for Overvoltage Detection. OV is referenced to VEE. When OV is pulled above
VOVH voltage, the GATE pin is immediately pulled low. The GATE pin remains low until the
OV pin voltage reduces to VOVL.UV
Input Pin for Undervoltage Detection. UV is referenced to VEE. When UV is pulled above
VUVH voltage, the GATE is enabled. When UV is pulled below VUVL, GATE is pulled low.
UV is also used to reset the circuit breaker after a fault condition. To reset the circuit
breaker, pull UV below VUVL. The reset command can be issued immediately after a fault
condition; however, the device does not restart until a tOFF delay time has elapsed after
the fault.VEEDevice Negative Power-Supply Input. Connect to the negative power-supply rail.5SENSE
Current-Sense Voltage Input. Connect to an external sense resistor and the external
MOSFET source. The voltage drop across the external sense resistor is monitored to detect
overcurrent or short-circuit fault conditions. Connect SENSE to VEE to disable the current-
limiting feature.6GATEGate Drive Output. Connect to gate of the external N-channel MOSFET.7DRAIN
Output-Voltage Sense Input. Connect to the output-voltage node (drain of external
N-channel MOSFET). Place the MAX5920_ so the DRAIN pin is close to the DRAIN of the
external MOSFET for the best thermal protection.VDDPositive Power-Supply Rail Input. This is the power ground in the negative-supply voltage
system. Connect to the higher potential of the power-supply inputs.
Board Insertion
Figure6a shows a typical hot-swap circuit for -48V sys-
tems. When the circuit board first makes contact with
the backplane, the DRAIN to GATE capacitance (Cgd)
of Q1 pulls up the GATE voltage to roughly IVEE x Cgd /
Cgd + CgsI. The MAX5920_ features an internal dynam-
ic clamp between GATE and VEEto keep the gate-to-
source voltage of Q1 low during hot insertion,
preventing Q1 from passing an uncontrolled current to
the load. For most applications, the internal clamp
between GATE and VEEof the MAX5920A/MAX5920B
eliminates the need for an external gate-to-source
capacitor. Resistor R3 limits the current into the clamp
circuitry during card insertion.
Power-Supply Ramping
The MAX5920A/MAX5920B can reside either on the
backplane or the removable circuit board (Figure6a).
Power is delivered to the load by placing an external
N-channel MOSFET pass transistor in the power-supply
path.
After the circuit board is inserted into the backplane
and the supply voltage at VEEis stable and within the
undervoltage and overvoltage tolerance, the
MAX5920A/MAX5920B turn on Q1. The MAX5920A/
MAX5920B gradually turn on the external MOSFET by
charging the gate of Q1 with a 45µA current source.
Capacitor C2 provides a feedback signal to accurately
limit the inrush current. The inrush current can be
calculated:
IINRUSH= IPU x CL / C2
where CLis the total load capacitance, C3 + C4, and
IPUis the MAX5920_ gate pullup current.
Figure6b shows the inrush current waveform. The cur-
rent through C2 controls the GATE voltage. At the end
of the DRAIN ramp, the GATE voltage is charged to its
final value. The GATE-to-SENSE clamp limits the maxi-
mum VGSto about 18V under any condition.
Board Removal
If the circuit card is removed from the backplane, the volt-
age at the UV pin falls below the UVLO detect threshold,
and the MAX5920_ turns off the external MOSFET.
Current Limit and Electronic
Circuit Breaker
The MAX5920_ provides current-limiting and circuit-
breaker features that protect against excessive load cur-
rent and short-circuit conditions. The load current is
monitored by sensing the voltage across an external
sense resistor connected between VEEand SENSE.
MAX5920
-48V Hot-Swap Controller
with External RSENSE
VEESENSEGATEDRAIN
VDD
PWRGD
MAX5920B
-48V RTN
-48V
549kΩ
6.49kΩ
10kΩ
0.02Ω
1kΩ
10Ω
C1**
470nF
25V
IRF530
15nF
100V
GATE IN
VICOR
VI-J3D-CY
VIN+
VIN-
100μF
100V
0.1μF
100V
10nF
-48V RTN
(SHORT PIN)
*DIODES INC. SMAT70A.
**OPTIONAL.
Figure 6a. Inrush Control Circuitry

Partno	Mfg	Dc	Qty	Available	Descript
MAX5920AESA+ \|MAX5920AESA	MAXIM	N/a	4884	avai	-48V Hot-Swap Controller with External RSENSE